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2024,43(6):6-16
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.002
Abstract:
Global climate change poses significant challenges to the sustainable development of agriculture worldwide. The domestic and international progress in three aspects including the sustainable development of agriculture， the impact of global climate change on the sustainable development of agriculture， and the human actions in response to global climate change for the sustainable development of agriculture were systematically reviewed based on the main topic of “Sustainable Development of Agriculture in the Context of Global Climate Change” and aimed at global food security and strategies for ecological security. The knowledge， methods， and tools from geography， management， agronomy， and economics were integrated based on the global goals of sustainable development. The contents of five interdisciplinary studies including the development and utilization of agricultural resources， the protection of farmland and food security systems， the transformation of patterns of agricultural and ecological security and models of development， strategies and strategic planning for the sustainable development of agriculture in the context of global climate change were proposed according to the interdisciplinary nature， comprehensive knowledge， and scientific frontiers of the main topic. The interdisciplinary research system of the sustainable development of agriculture in the context of global climate change was prospected from directions of interdisciplinary research including the governance of global climate， the transformation of agro-food system， the resilience of urban and rural climate， the system of smart agroforestry， the utilization of natural resources and the protection of ecosystem under the advanced ideas and concepts of “community of Earth destiny” and “community of human destiny”. It will provide reference for building an interdisciplinary studies and collaborative education model， and exploring the pathway of global governance for the sustainable development of agriculture.
Global climate change poses significant challenges to the sustainable development of agriculture worldwide. The domestic and international progress in three aspects including the sustainable development of agriculture， the impact of global climate change on the sustainable development of agriculture， and the human actions in response to global climate change for the sustainable development of agriculture were systematically reviewed based on the main topic of “Sustainable Development of Agriculture in the Context of Global Climate Change” and aimed at global food security and strategies for ecological security. The knowledge， methods， and tools from geography， management， agronomy， and economics were integrated based on the global goals of sustainable development. The contents of five interdisciplinary studies including the development and utilization of agricultural resources， the protection of farmland and food security systems， the transformation of patterns of agricultural and ecological security and models of development， strategies and strategic planning for the sustainable development of agriculture in the context of global climate change were proposed according to the interdisciplinary nature， comprehensive knowledge， and scientific frontiers of the main topic. The interdisciplinary research system of the sustainable development of agriculture in the context of global climate change was prospected from directions of interdisciplinary research including the governance of global climate， the transformation of agro-food system， the resilience of urban and rural climate， the system of smart agroforestry， the utilization of natural resources and the protection of ecosystem under the advanced ideas and concepts of “community of Earth destiny” and “community of human destiny”. It will provide reference for building an interdisciplinary studies and collaborative education model， and exploring the pathway of global governance for the sustainable development of agriculture.
2024,43(6):17-28
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.003
Abstract:
Natural resources can regulate the balance of ecology， provide a good environment and economic foundation for society， and are the material basis for the survival and development of human. Therefore， firmly holding the bottom line of utilizing natural resources and strengthening the protection of the rights and interests of natural resource assets are key factors in promoting the harmonious coexistence between human and nature in the development of modernization. This article analyzed the four stages of the process of developing and protecting natural resources through historical analysis and inductive deduction， clarified the certainty of harmonious coexistence between humans and nature in the development of modernization， proposed the characteristics of developing and protecting of natural resources in the new era， and constructed a path for realizing the development and protection of natural resources to provide theoretical and practical guidance for the construction of harmonious coexistence between humans and nature in the development of modernization. The results showed that the harmonious coexistence between humans and nature in the development of modernization transcended the concepts， methods， and theories of ecological modernization in Western world. The development and protection of natural resources in the new era emphasizes the sustainable development， legalization and standardization， systematic and comprehensive management， and technological innovation. The development and protection of natural resources should adhere to the concept of a community of shared life between humans and nature， adhere to the thinking of systematic governance， strengthen the construction of digital information， promote the development with green and low-carbon， improve the system for natural resources， and enhance the level of supervision and regulation.
Natural resources can regulate the balance of ecology， provide a good environment and economic foundation for society， and are the material basis for the survival and development of human. Therefore， firmly holding the bottom line of utilizing natural resources and strengthening the protection of the rights and interests of natural resource assets are key factors in promoting the harmonious coexistence between human and nature in the development of modernization. This article analyzed the four stages of the process of developing and protecting natural resources through historical analysis and inductive deduction， clarified the certainty of harmonious coexistence between humans and nature in the development of modernization， proposed the characteristics of developing and protecting of natural resources in the new era， and constructed a path for realizing the development and protection of natural resources to provide theoretical and practical guidance for the construction of harmonious coexistence between humans and nature in the development of modernization. The results showed that the harmonious coexistence between humans and nature in the development of modernization transcended the concepts， methods， and theories of ecological modernization in Western world. The development and protection of natural resources in the new era emphasizes the sustainable development， legalization and standardization， systematic and comprehensive management， and technological innovation. The development and protection of natural resources should adhere to the concept of a community of shared life between humans and nature， adhere to the thinking of systematic governance， strengthen the construction of digital information， promote the development with green and low-carbon， improve the system for natural resources， and enhance the level of supervision and regulation.
2024,43(6):29-38
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.004
Abstract:
Soil erosion poses a threat to food security and ecosystem services， and is one of the severe environmental problems facing China. It is affected by both natural factors and human activities. At present， a large number of studies in China have focused on the driving effect of socio-economic factors on soil erosion， but there are still insufficient in studying the spatial non-stationary relationship between the two and paying attention to the scale differences of affecting factors. 346 prefecture-level cities in China were used to study the complex driving mechanisms of socio-economic activities on soil erosion. The soil erosion prediction （RUSLE） model and multiscale geographically weighted regression （MGWR） model were used to investigate the spatial heterogeneity of soil erosion in various cities in China using 2017 as a reference year. The spatial driving effects of socio-economic factors on rates of soil erosion in prefecture-level cities across China and the differences in the scale of action between factors were studied. Results showed that the spatial distribution of the rate of soil erosion in various prefecture-level cities in China had a significant positive spatial correlation. Hotspots of soil erosion were mainly distributed in the west， northeast， the Yunnan-Guizhou Plateau， Sichuan Basin and the Loess Plateau. Compared with models based on global regression and traditional geographically weighted regression models， MGWR significantly improved the explanatory power of socio-economic variables on the rate of soil erosion， with a model fitting goodness of 0.87. From the perspective of driving factors， the direction of the effect of each driving factor on the rate of soil erosion in various prefecture-level cities in China had structural differences with changes of spatial location except for the factor of regional gross domestic product per capita. On average， population density was the factor contributing the most to the rate of soil erosion in various prefecture-level cities in China. The rate of soil erosion in prefecture level cities in China was more susceptible to the influence of multiple cropping indices in the western region， while the driving mechanism of socio-economic factors on the rate of soil erosion in the eastern region was more complex， and the spatial scale differences of different driving factors were more obvious. It is indicated that decision makers should fully consider the spatial heterogeneity of the impact of human activities on soil erosion to achieve the sustainable development of soil and water conservation.
Soil erosion poses a threat to food security and ecosystem services， and is one of the severe environmental problems facing China. It is affected by both natural factors and human activities. At present， a large number of studies in China have focused on the driving effect of socio-economic factors on soil erosion， but there are still insufficient in studying the spatial non-stationary relationship between the two and paying attention to the scale differences of affecting factors. 346 prefecture-level cities in China were used to study the complex driving mechanisms of socio-economic activities on soil erosion. The soil erosion prediction （RUSLE） model and multiscale geographically weighted regression （MGWR） model were used to investigate the spatial heterogeneity of soil erosion in various cities in China using 2017 as a reference year. The spatial driving effects of socio-economic factors on rates of soil erosion in prefecture-level cities across China and the differences in the scale of action between factors were studied. Results showed that the spatial distribution of the rate of soil erosion in various prefecture-level cities in China had a significant positive spatial correlation. Hotspots of soil erosion were mainly distributed in the west， northeast， the Yunnan-Guizhou Plateau， Sichuan Basin and the Loess Plateau. Compared with models based on global regression and traditional geographically weighted regression models， MGWR significantly improved the explanatory power of socio-economic variables on the rate of soil erosion， with a model fitting goodness of 0.87. From the perspective of driving factors， the direction of the effect of each driving factor on the rate of soil erosion in various prefecture-level cities in China had structural differences with changes of spatial location except for the factor of regional gross domestic product per capita. On average， population density was the factor contributing the most to the rate of soil erosion in various prefecture-level cities in China. The rate of soil erosion in prefecture level cities in China was more susceptible to the influence of multiple cropping indices in the western region， while the driving mechanism of socio-economic factors on the rate of soil erosion in the eastern region was more complex， and the spatial scale differences of different driving factors were more obvious. It is indicated that decision makers should fully consider the spatial heterogeneity of the impact of human activities on soil erosion to achieve the sustainable development of soil and water conservation.
2024,43(6):39-52
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.005
Abstract:
The differences in spatial patterns of population shrinkage in rural areas within counties and their influencing factors were analyzed to provide empirical evidence and scientific guidance for analyzing the relationship between population and land in rural areas within counties and promoting efficient and intensive use of resources. The precise geographic data including residential patches of rural settlements and LandScan - a high-resolution population distribution dataset- were used to innovatively construct a population shrinkage index. This index was used systematically to detect the dynamic changes in population density of rural areas in China at the patch scale from 2000 to 2020. The spatial patterns of population shrinkage in rural areas across 2 847 counties in China was comprehensively analyzed. The results showed that patches of population shrinkage were prominently concentrated in the Huaihe River Basin， with mild shrinkage mainly observed in rural areas in the western region and severe shrinkage in rural areas along the eastern coast. The population shrinkage in rural areas within counties had significant regional differences， forming a spatial pattern of “two belts and multiple agglomerations”. Counties （cities） with different administrative divisions exhibited differentiated characteristics of population shrinkage. Urbanization （UR）， education service （EDU）， and agricultural mechanization （ARG） were the three pivotal factors affecting the internal population shrinkage in rural areas within counties in China. The interplay between educational service and rural income had the strongest explanatory power.It will provide a robust empirical foundation and scientific direction for dissecting the population -land nexus within counties， refining the plans for rural settlement， and advocating for the efficient， intensive utilization of resources.
The differences in spatial patterns of population shrinkage in rural areas within counties and their influencing factors were analyzed to provide empirical evidence and scientific guidance for analyzing the relationship between population and land in rural areas within counties and promoting efficient and intensive use of resources. The precise geographic data including residential patches of rural settlements and LandScan - a high-resolution population distribution dataset- were used to innovatively construct a population shrinkage index. This index was used systematically to detect the dynamic changes in population density of rural areas in China at the patch scale from 2000 to 2020. The spatial patterns of population shrinkage in rural areas across 2 847 counties in China was comprehensively analyzed. The results showed that patches of population shrinkage were prominently concentrated in the Huaihe River Basin， with mild shrinkage mainly observed in rural areas in the western region and severe shrinkage in rural areas along the eastern coast. The population shrinkage in rural areas within counties had significant regional differences， forming a spatial pattern of “two belts and multiple agglomerations”. Counties （cities） with different administrative divisions exhibited differentiated characteristics of population shrinkage. Urbanization （UR）， education service （EDU）， and agricultural mechanization （ARG） were the three pivotal factors affecting the internal population shrinkage in rural areas within counties in China. The interplay between educational service and rural income had the strongest explanatory power.It will provide a robust empirical foundation and scientific direction for dissecting the population -land nexus within counties， refining the plans for rural settlement， and advocating for the efficient， intensive utilization of resources.
2024,43(6):53-64
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.006
Abstract:
28 by-laws of Nature-based Solutions （NbS） global guidelines were localized and translated， and 28 localized indexes combined with the connotation requirements of comprehensive land consolidation in rural areas were constructed and proposed to promote the localization of the NbS Global Guidelines for comprehensive land consolidation in rural areas. An empirical evaluation was conducted using the comprehensive land consolidation project in Yuquan Subdistrict Office of Dangyang City， Hubei Province as an example. The results showed that this project performed well in scale-based design， inclusive governance， economic feasibility， and adaptive management， well in identifying social challenges， net benefits of biodiversity， mainstreaming， and sustainable development， but was weak in trade-off mechanisms. It is indicated that the 28 localized evaluation indexes constructed are easy to quantify and can serve as an effective set of tools for decision-makers and practitioners to conduct self-assessment of NbS localization.
28 by-laws of Nature-based Solutions （NbS） global guidelines were localized and translated， and 28 localized indexes combined with the connotation requirements of comprehensive land consolidation in rural areas were constructed and proposed to promote the localization of the NbS Global Guidelines for comprehensive land consolidation in rural areas. An empirical evaluation was conducted using the comprehensive land consolidation project in Yuquan Subdistrict Office of Dangyang City， Hubei Province as an example. The results showed that this project performed well in scale-based design， inclusive governance， economic feasibility， and adaptive management， well in identifying social challenges， net benefits of biodiversity， mainstreaming， and sustainable development， but was weak in trade-off mechanisms. It is indicated that the 28 localized evaluation indexes constructed are easy to quantify and can serve as an effective set of tools for decision-makers and practitioners to conduct self-assessment of NbS localization.
2024,43(6):65-74
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.007
Abstract:
The impact and pathways of changes in land use on carbon emissions in the context of carbon peaking and carbon neutrality （double carbon） were studied from the perspective of transforming farmland into construction land to promote the collaborative governance of ecological environment and achieve the development with green and high-quality. A panel fixed effects model was used to investigate the effects and mechanisms of transforming farmland into construction land on carbon emission based on the data of 224 prefecture-level cities in China from 2009- ![]()
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The impact and pathways of changes in land use on carbon emissions in the context of carbon peaking and carbon neutrality （double carbon） were studied from the perspective of transforming farmland into construction land to promote the collaborative governance of ecological environment and achieve the development with green and high-quality. A panel fixed effects model was used to investigate the effects and mechanisms of transforming farmland into construction land on carbon emission based on the data of 224 prefecture-level cities in China from 2009
2024,43(6):75-86
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.008
Abstract:
Guangzhou City was used to study the characteristics of differentiated distribution and influencing factors of carbon emissions at the level of town and street governance units.A top-down approach to spatial econometric methods for carbon emissions was used to calculate the total carbon emissions and intensity of 175 town and street units in 2020 and analyze the heterogeneous spatial distribution characteristics of carbon emissions in different types of town and street units.The IPAT model and Spearman correlation analysis was used to screen influencing factors and construct a ridge regression model.Differentiated factors of governance and strategies for reducing carbon emissions at levels of town and street governance units were obtained.The results showed that the total carbon emissions of street units in Guangzhou City were much higher than those of town units，but the per capita carbon emissions of town units were much higher than those of street units.Among them，the per capita carbon emission of industrial towns（14.37 t） were about five times that of streets with commercial offices（2.89 t）.The total carbon emissions and intensity had a circular pattern of " low-inner，high-middle，low-outer " in terms of spatial distribution，but high-value areas of total carbon emissions were concentrated in the suburbs，and high-value areas of per capita carbon emissions were concentrated in the far suburbs.The indexes of urban construction including the population density，the rate of urbanization，and the structure of construction land were strongly correlated with carbon emissions based on analyzing factors affecting carbon emission at different levels of town and street governance units，but different types of street and town units had significantly differential effects.It is indicated that differentiated pathways of carbon reduction including “controlling the total amount” and “controlling the intensity” should be proposed for different types of streets and towns.
Guangzhou City was used to study the characteristics of differentiated distribution and influencing factors of carbon emissions at the level of town and street governance units.A top-down approach to spatial econometric methods for carbon emissions was used to calculate the total carbon emissions and intensity of 175 town and street units in 2020 and analyze the heterogeneous spatial distribution characteristics of carbon emissions in different types of town and street units.The IPAT model and Spearman correlation analysis was used to screen influencing factors and construct a ridge regression model.Differentiated factors of governance and strategies for reducing carbon emissions at levels of town and street governance units were obtained.The results showed that the total carbon emissions of street units in Guangzhou City were much higher than those of town units，but the per capita carbon emissions of town units were much higher than those of street units.Among them，the per capita carbon emission of industrial towns（14.37 t） were about five times that of streets with commercial offices（2.89 t）.The total carbon emissions and intensity had a circular pattern of " low-inner，high-middle，low-outer " in terms of spatial distribution，but high-value areas of total carbon emissions were concentrated in the suburbs，and high-value areas of per capita carbon emissions were concentrated in the far suburbs.The indexes of urban construction including the population density，the rate of urbanization，and the structure of construction land were strongly correlated with carbon emissions based on analyzing factors affecting carbon emission at different levels of town and street governance units，but different types of street and town units had significantly differential effects.It is indicated that differentiated pathways of carbon reduction including “controlling the total amount” and “controlling the intensity” should be proposed for different types of streets and towns.
2024,43(6):87-99
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.009
Abstract:
It is of great significance to study the spatiotemporal characteristics of agricultural carbon emissions and its strategies for realizing the target of carbon peak and carbon neutrality in China. Hefei City was used to study the spatiotemporal characteristics and regulation strategies of agricultural carbon emissions at the level of county. The greenhouse gases generated during the production process of planting and animal husbandry were used as the main carbon source to construct a measurement index system for carbon emissions from four levels including the utilization of agricultural energy， the input of agricultural material， the planting of rice， and the farming of livestock and poultry. A calculation model of agricultural carbon emission was constructed based on the IPCC inventory method. The agricultural carbon emission and carbon emission intensity of Hefei City at the level of county from 2003 to 2022 were calculated. The spatiotemporal characteristics of carbon emission were analyzed with standard deviation ellipse and center of gravity transfer model， ArcGIS visualization method. The results show that the total agricultural carbon emissions of counties in Hefei are 1 213 380-1 410 320 tons in terms of total agricultural carbon emissions and intensity， and the overall trend is “first slowly rising to the peak， and then gradually decreasing”. Agricultural carbon emission intensity is 0.482-2.358 tons/ten thousand yuan， and the overall downward trend is obvious； From 2003 to 2005， the agricultural carbon emissions of counties in Hefei were mostly concentrated in Lujiang County and Feidong County， with a slight difference between the north and the south. From 2006 to 2022， the spatial pattern of “high in the north and low in the south” increased. The spatial distribution characteristics of carbon emission intensity changed greatly， showing the spatial pattern of “north high and south low”，“north low and south high” and “northeast high and northwest low” in three time periods from 2003 to 2007， 2008 to 2017 and 2018 to 2022 respectively. From the agricultural carbon emission center of gravity， the agricultural carbon emission center of Hefei is northeast as a whole.From 2003 to 2022， the total migration was about 17.75 km. It will provide some references for calculating agricultural carbon emissions and the formulating policies of reducing agricultural carbon emissions in China.
It is of great significance to study the spatiotemporal characteristics of agricultural carbon emissions and its strategies for realizing the target of carbon peak and carbon neutrality in China. Hefei City was used to study the spatiotemporal characteristics and regulation strategies of agricultural carbon emissions at the level of county. The greenhouse gases generated during the production process of planting and animal husbandry were used as the main carbon source to construct a measurement index system for carbon emissions from four levels including the utilization of agricultural energy， the input of agricultural material， the planting of rice， and the farming of livestock and poultry. A calculation model of agricultural carbon emission was constructed based on the IPCC inventory method. The agricultural carbon emission and carbon emission intensity of Hefei City at the level of county from 2003 to 2022 were calculated. The spatiotemporal characteristics of carbon emission were analyzed with standard deviation ellipse and center of gravity transfer model， ArcGIS visualization method. The results show that the total agricultural carbon emissions of counties in Hefei are 1 213 380-1 410 320 tons in terms of total agricultural carbon emissions and intensity， and the overall trend is “first slowly rising to the peak， and then gradually decreasing”. Agricultural carbon emission intensity is 0.482-2.358 tons/ten thousand yuan， and the overall downward trend is obvious； From 2003 to 2005， the agricultural carbon emissions of counties in Hefei were mostly concentrated in Lujiang County and Feidong County， with a slight difference between the north and the south. From 2006 to 2022， the spatial pattern of “high in the north and low in the south” increased. The spatial distribution characteristics of carbon emission intensity changed greatly， showing the spatial pattern of “north high and south low”，“north low and south high” and “northeast high and northwest low” in three time periods from 2003 to 2007， 2008 to 2017 and 2018 to 2022 respectively. From the agricultural carbon emission center of gravity， the agricultural carbon emission center of Hefei is northeast as a whole.From 2003 to 2022， the total migration was about 17.75 km. It will provide some references for calculating agricultural carbon emissions and the formulating policies of reducing agricultural carbon emissions in China.
2024,43(6):100-113
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.010
Abstract:
An evaluation system for urban-rural integration indexes was constructed to promote the integrated development of urban and rural areas in Jiangsu Province and other regions. The natural discontinuity method， nuclear density estimation method and exploratory spatial analysis method were combined to describe the spatiotemporal distribution and evolution of urban-rural integration in counties in Jiangsu Province from 2013 to 2021. The internal obstacles and external driving factors of urban-rural integration in counties in Jiangsu Province were identified based on obstacle degree model and geographic detector model. The results showed that the level of urban-rural integration in counties in Jiangsu Province had continued to rise since 2013， but there were differences in the level of urban-rural integration between counties and the differences were still expanding. The integration level of each dimension by 2021 from high to low was as follows： social integration， ecological integration， spatial integration， economic integration， and population integration. The integration level of each region from high to low was as follows： southern Jiangsu region， central Jiangsu region， and northern Jiangsu region. There was a global spatial positive correlation between urban and rural integration in counties in Jiangsu Province， and the local spatial distribution pattern was characterized by high-high agglomeration type and low-low agglomeration type， with low-level agglomeration accounting for the main part. Overall， the low level of industrial structure and employment structure， the deviation between industrial structure and employment structure， were the main internal obstacles to the integrated development of urban and rural areas in counties in Jiangsu Province. There were differences in the resistance levels of various obstacles in the southern， central， and northern regions of Jiangsu from a regional perspective. Digital technology was an important external driving force for the integration of urban and rural areas in counties in Jiangsu Province. Among them， the digitalization of rural economy had the most obvious driving effect on the integration of urban and rural areas， and digital marketing was the main driving path. It is believed that efforts should be made to strengthen communication and interaction between counties， and promote coordinated and balanced development among them； optimize the industrial structure and employment structure of counties simultaneously， adapt to local conditions， target the advantages and disadvantages of each county， and break down obstacles to the integrated development of urban and rural areas in counties in Jiangsu Province. Focus should be put on supporting the application of digital technology in the rural economy， cultivating new business models represented by rural e-commerce， and helping the integrated development of urban and rural areas in counties to reach a new level.
An evaluation system for urban-rural integration indexes was constructed to promote the integrated development of urban and rural areas in Jiangsu Province and other regions. The natural discontinuity method， nuclear density estimation method and exploratory spatial analysis method were combined to describe the spatiotemporal distribution and evolution of urban-rural integration in counties in Jiangsu Province from 2013 to 2021. The internal obstacles and external driving factors of urban-rural integration in counties in Jiangsu Province were identified based on obstacle degree model and geographic detector model. The results showed that the level of urban-rural integration in counties in Jiangsu Province had continued to rise since 2013， but there were differences in the level of urban-rural integration between counties and the differences were still expanding. The integration level of each dimension by 2021 from high to low was as follows： social integration， ecological integration， spatial integration， economic integration， and population integration. The integration level of each region from high to low was as follows： southern Jiangsu region， central Jiangsu region， and northern Jiangsu region. There was a global spatial positive correlation between urban and rural integration in counties in Jiangsu Province， and the local spatial distribution pattern was characterized by high-high agglomeration type and low-low agglomeration type， with low-level agglomeration accounting for the main part. Overall， the low level of industrial structure and employment structure， the deviation between industrial structure and employment structure， were the main internal obstacles to the integrated development of urban and rural areas in counties in Jiangsu Province. There were differences in the resistance levels of various obstacles in the southern， central， and northern regions of Jiangsu from a regional perspective. Digital technology was an important external driving force for the integration of urban and rural areas in counties in Jiangsu Province. Among them， the digitalization of rural economy had the most obvious driving effect on the integration of urban and rural areas， and digital marketing was the main driving path. It is believed that efforts should be made to strengthen communication and interaction between counties， and promote coordinated and balanced development among them； optimize the industrial structure and employment structure of counties simultaneously， adapt to local conditions， target the advantages and disadvantages of each county， and break down obstacles to the integrated development of urban and rural areas in counties in Jiangsu Province. Focus should be put on supporting the application of digital technology in the rural economy， cultivating new business models represented by rural e-commerce， and helping the integrated development of urban and rural areas in counties to reach a new level.
2024,43(6):114-126
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.011
Abstract:
Changing the traditional model of development was studied to optimize the green transformation of the whole society and the path of promoting the development with green， low-carbon and recycle in the face of resource scarcity and increasing emissions of carbon. An indexes system was constructed based on the panel data of 30 provinces in China from 2010 to 2021. The entropy weighted technique for order preference by similarity to an ideal solution （TOPSIS） model， coupling and coordination degree model and spatial autocorrelation model， the coupling and coordination degree of digital economy were used to analyze the coupling and coordination degree and spatiotemporal evolution of the three systems including digital economy， development with low-carbon， and new urbanization. The results showed that the comprehensive development level of the three systems was significantly improved from 2010 to 2021， showing a spatial distribution characteristic of “high in the east and low in the west” from a regional perspective. The coupling and coordination degree of the three systems had a fluctuating upward trend， and the overall level went from barely coordination to basic coordination， with a low overall level. The three systems exhibited positive spatial autocorrelation in space， with the correlation gradually increasing and the spatial distribution evolving towards the state of aggregation. The high-high agglomeration type was mainly distributed in the southeastern coastal and central areas and had a significant diffusion trend， with a coordinated development level of “high in the southeast and low in the northwest”. Suggestions are proposed for the coupling and coordination of digital economy， development with low-carbon， and new urbanization based on results of empirical analyses. It will provide reference for strengthening regional action in chain， filling the weak spots， and promoting the development with green， low-carbon， and recycle.
Changing the traditional model of development was studied to optimize the green transformation of the whole society and the path of promoting the development with green， low-carbon and recycle in the face of resource scarcity and increasing emissions of carbon. An indexes system was constructed based on the panel data of 30 provinces in China from 2010 to 2021. The entropy weighted technique for order preference by similarity to an ideal solution （TOPSIS） model， coupling and coordination degree model and spatial autocorrelation model， the coupling and coordination degree of digital economy were used to analyze the coupling and coordination degree and spatiotemporal evolution of the three systems including digital economy， development with low-carbon， and new urbanization. The results showed that the comprehensive development level of the three systems was significantly improved from 2010 to 2021， showing a spatial distribution characteristic of “high in the east and low in the west” from a regional perspective. The coupling and coordination degree of the three systems had a fluctuating upward trend， and the overall level went from barely coordination to basic coordination， with a low overall level. The three systems exhibited positive spatial autocorrelation in space， with the correlation gradually increasing and the spatial distribution evolving towards the state of aggregation. The high-high agglomeration type was mainly distributed in the southeastern coastal and central areas and had a significant diffusion trend， with a coordinated development level of “high in the southeast and low in the northwest”. Suggestions are proposed for the coupling and coordination of digital economy， development with low-carbon， and new urbanization based on results of empirical analyses. It will provide reference for strengthening regional action in chain， filling the weak spots， and promoting the development with green， low-carbon， and recycle.
2024,43(6):127-140
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.012
Abstract:
Improving the green utilization efficiency of industrial land is an important way to achieve sustainable land use and development of industrial economy with high-quality， and the agglomeration of manufacturing （AGG） industry is an important factor affecting the green utilization efficiency of industrial land （EIL）. The panel data from 30 provinces in China from 2000 to 2019 were used to study the mechanism and effects of manufacturing agglomeration （AGG） on the green utilization efficiency of industrial land （EIL） from the perspective of environmental regulation （ER）. The results showed that the green utilization efficiency of industrial land （EIL） in China from 2000 to 2019 had a trend of steady increase followed by rapid growth， with an average annual growth rate of 2.942%. The green utilization efficiency of industrial land （EIL） in the eastern region of China remained higher than that in the central and western regions of China， with an average annual growth rate of 4.993% and 1.061%， respectively. The effects of manufacturing agglomeration （AGG） on the green utilization efficiency of industrial land （EIL） had a threshold characteristic with the changes in the intensity of environmental regulation （ER）. There was a U-shaped relationship between the manufacturing agglomeration （AGG） and the green utilization efficiency of industrial land （EIL） with the increase of the intensity of environmental regulation （ER）. It was found from heterogeneity analyses that the negative effect of AGG on EIL gradually weakened with the improvement in the level of ER from 2000 to 2009， and had a negative to positive trend from 2010 to 2019. Voluntary ER was the first to generate a threshold effect， while market-oriented and command-and-control types of ER were observed to manifest at a higher level of ER. It is indicated that the differentiated policies for environmental regulation （ER） should be formulated to upgrade the industrial structure of manufacturing industry and the green utilization of industrial land.
Improving the green utilization efficiency of industrial land is an important way to achieve sustainable land use and development of industrial economy with high-quality， and the agglomeration of manufacturing （AGG） industry is an important factor affecting the green utilization efficiency of industrial land （EIL）. The panel data from 30 provinces in China from 2000 to 2019 were used to study the mechanism and effects of manufacturing agglomeration （AGG） on the green utilization efficiency of industrial land （EIL） from the perspective of environmental regulation （ER）. The results showed that the green utilization efficiency of industrial land （EIL） in China from 2000 to 2019 had a trend of steady increase followed by rapid growth， with an average annual growth rate of 2.942%. The green utilization efficiency of industrial land （EIL） in the eastern region of China remained higher than that in the central and western regions of China， with an average annual growth rate of 4.993% and 1.061%， respectively. The effects of manufacturing agglomeration （AGG） on the green utilization efficiency of industrial land （EIL） had a threshold characteristic with the changes in the intensity of environmental regulation （ER）. There was a U-shaped relationship between the manufacturing agglomeration （AGG） and the green utilization efficiency of industrial land （EIL） with the increase of the intensity of environmental regulation （ER）. It was found from heterogeneity analyses that the negative effect of AGG on EIL gradually weakened with the improvement in the level of ER from 2000 to 2009， and had a negative to positive trend from 2010 to 2019. Voluntary ER was the first to generate a threshold effect， while market-oriented and command-and-control types of ER were observed to manifest at a higher level of ER. It is indicated that the differentiated policies for environmental regulation （ER） should be formulated to upgrade the industrial structure of manufacturing industry and the green utilization of industrial land.
2024,43(6):141-149
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.013
Abstract:
The effect of spatial non-integration between the administrative regions and economic zones in China has always existed， and administrative divisions have become an important means of spatial governance in recent years， laying the foundation for solving the problem of developing cross regional spaces with high-quality. The Beijing-Tianjin-Hebei agglomeration was used to study the spatiotemporal changes， spatial spillover effects， and mechanisms of driving land development intensity. The adjacency relationships between county-level administrative units were embedded into the spatial econometric model to further investigate the impact of administrative spatial spillover on land development intensity under different scenarios of spatial adjacency. The results showed that there was a significant difference in the land development intensity among administrative units within the Beijing-Tianjin-Hebei agglomeration， with significant spatiotemporal differentiation and spatial agglomeration. From a spatial perspective， the overall land development intensity in the Beijing-Tianjin-Hebei agglomeration had a significant upward trend， but the overall spatial pattern of "high in the southeast and low in the northwest" was not broken. Population density， the proportion of added value of the tertiary industry， and per capita GDP had a significant impact on the land development intensity. The correlation between the land development intensity and the spatial distribution was significantly positive and spatial， with obviously direct spatial spillover. The administrative spatial spillover of different adjacency relationships was different and the spatial spillover of adjacency scenarios of county-level administrative units was enhanced from 2010 to 2019. It is indicated that the administrative spatial spillover of land development intensity should be fully utilized to achieve balanced regional development in the future.
The effect of spatial non-integration between the administrative regions and economic zones in China has always existed， and administrative divisions have become an important means of spatial governance in recent years， laying the foundation for solving the problem of developing cross regional spaces with high-quality. The Beijing-Tianjin-Hebei agglomeration was used to study the spatiotemporal changes， spatial spillover effects， and mechanisms of driving land development intensity. The adjacency relationships between county-level administrative units were embedded into the spatial econometric model to further investigate the impact of administrative spatial spillover on land development intensity under different scenarios of spatial adjacency. The results showed that there was a significant difference in the land development intensity among administrative units within the Beijing-Tianjin-Hebei agglomeration， with significant spatiotemporal differentiation and spatial agglomeration. From a spatial perspective， the overall land development intensity in the Beijing-Tianjin-Hebei agglomeration had a significant upward trend， but the overall spatial pattern of "high in the southeast and low in the northwest" was not broken. Population density， the proportion of added value of the tertiary industry， and per capita GDP had a significant impact on the land development intensity. The correlation between the land development intensity and the spatial distribution was significantly positive and spatial， with obviously direct spatial spillover. The administrative spatial spillover of different adjacency relationships was different and the spatial spillover of adjacency scenarios of county-level administrative units was enhanced from 2010 to 2019. It is indicated that the administrative spatial spillover of land development intensity should be fully utilized to achieve balanced regional development in the future.
2024,43(6):150-160
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.014
Abstract:
The green space of Luojiagang Greenbelt Park in Wuhan and its surrounding built environment were used to study the mechanism and effect of urban greenbelts on reducing particulate matter in the air. Three days with clear and windless weather and similar meteorological conditions in winter were repeatedly observed. A combination of land use regression （LUR） model and principal component analysis （PCA） was used to analyze the effect of urban greenbelt on mitigating the concentration of PM10 and PM2.5 in the air in winter and identify the key influencing factors. The results showed that there was a width effect of urban greenbelt on mitigating the PM10 and PM2.5 in the air in winter based on the LUR model. The green space with a width of 30-40 meters had the most significant mitigation efficiency of PM10 in the air in winter. In winter， the concentration of PM10 and PM2.5 in the air inside urban greenbelt was higher than that in adjacent road locations. There was a significant accumulation effect of PM10 and PM2.5 in the air in urban greenbelt. It is indicated that the effect of urban greenbelt on mitigating the PM10 and PM2.5 in the air was disturbed by emissions of surrounding traffic pollution. The micro-meteorological conditions created by green spaces of different widths can have a certain impact on the concentration of PM10 and PM2.5 in the air.
The green space of Luojiagang Greenbelt Park in Wuhan and its surrounding built environment were used to study the mechanism and effect of urban greenbelts on reducing particulate matter in the air. Three days with clear and windless weather and similar meteorological conditions in winter were repeatedly observed. A combination of land use regression （LUR） model and principal component analysis （PCA） was used to analyze the effect of urban greenbelt on mitigating the concentration of PM10 and PM2.5 in the air in winter and identify the key influencing factors. The results showed that there was a width effect of urban greenbelt on mitigating the PM10 and PM2.5 in the air in winter based on the LUR model. The green space with a width of 30-40 meters had the most significant mitigation efficiency of PM10 in the air in winter. In winter， the concentration of PM10 and PM2.5 in the air inside urban greenbelt was higher than that in adjacent road locations. There was a significant accumulation effect of PM10 and PM2.5 in the air in urban greenbelt. It is indicated that the effect of urban greenbelt on mitigating the PM10 and PM2.5 in the air was disturbed by emissions of surrounding traffic pollution. The micro-meteorological conditions created by green spaces of different widths can have a certain impact on the concentration of PM10 and PM2.5 in the air.
2024,43(6):161-170
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.015
Abstract:
The interceptor collection method was used to collect arthropod communities from six small and medium-sized parks within the third ring road of Beijing to study the relationship between the diversity of arthropods and microenvironmental factors in urban green spaces and promote the stability of ecosystems in urban green spaces.Pearson correlation analysis，regression analysis，and principal component analysis （PCA） were used to analyze the relationship between the diversity of arthropods and their natural enemies and the microenvironmental factors in urban green spaces.The results showed that Aphididae was the dominant family in arthropods，accounting for 52.12% of the total abundance.Diaeretiella rapae and Semidalis aleyrodiformes were the dominant species of aphidophagus predator insects，accounting for 27.73% and 23.92% of the total abundance，respectively.There were significant differences in the richness，abundance，and Shannon-Wiener index of predator insects among different plots.The areas，richness and Shannon Wiener index of flowering plants were significantly positively correlated with the abundance of arthropods（P<0.001），the richness（P<0.001） and the abundance（P<0.001） of aphidophagus predator insects，and significantly negatively correlated with the Shannon Wiener index of arthropod communities（P<0.001）.The frequency and dosage ratio of pesticide application were significantly positively correlated with the abundance of arthropods（P<0.001）.The results of principal component analysis showed that the main microenvironmental factors affecting the diversity of arthropods in urban green spaces included the dosage ratio of pesticide，the area of flowering plant，the frequency of pesticide application，the evenness of flowering plants，the Shannon Wiener diversity of flowering plants，and the abundance of flowering plants.The results of RDA analysis showed that the area，evenness，Shannon Wiener diversity and abundance of flowering plants were significantly positively correlated with the abundance of arthropods and aphidophagus predator insects，and significantly negatively correlated with the diversity of arthropods.The results of comprehensive ranking showed that the top three factors with the greatest influence were the dosage ratio of pesticide，the area of flowering plant and the frequency of pesticide application.The microenvironmental factors and their impacts on the diversity of arthropods in urban green spaces were preliminarily clarified.It will provide references for promoting the protection of biodiversity in urban green spaces.
The interceptor collection method was used to collect arthropod communities from six small and medium-sized parks within the third ring road of Beijing to study the relationship between the diversity of arthropods and microenvironmental factors in urban green spaces and promote the stability of ecosystems in urban green spaces.Pearson correlation analysis，regression analysis，and principal component analysis （PCA） were used to analyze the relationship between the diversity of arthropods and their natural enemies and the microenvironmental factors in urban green spaces.The results showed that Aphididae was the dominant family in arthropods，accounting for 52.12% of the total abundance.Diaeretiella rapae and Semidalis aleyrodiformes were the dominant species of aphidophagus predator insects，accounting for 27.73% and 23.92% of the total abundance，respectively.There were significant differences in the richness，abundance，and Shannon-Wiener index of predator insects among different plots.The areas，richness and Shannon Wiener index of flowering plants were significantly positively correlated with the abundance of arthropods（P<0.001），the richness（P<0.001） and the abundance（P<0.001） of aphidophagus predator insects，and significantly negatively correlated with the Shannon Wiener index of arthropod communities（P<0.001）.The frequency and dosage ratio of pesticide application were significantly positively correlated with the abundance of arthropods（P<0.001）.The results of principal component analysis showed that the main microenvironmental factors affecting the diversity of arthropods in urban green spaces included the dosage ratio of pesticide，the area of flowering plant，the frequency of pesticide application，the evenness of flowering plants，the Shannon Wiener diversity of flowering plants，and the abundance of flowering plants.The results of RDA analysis showed that the area，evenness，Shannon Wiener diversity and abundance of flowering plants were significantly positively correlated with the abundance of arthropods and aphidophagus predator insects，and significantly negatively correlated with the diversity of arthropods.The results of comprehensive ranking showed that the top three factors with the greatest influence were the dosage ratio of pesticide，the area of flowering plant and the frequency of pesticide application.The microenvironmental factors and their impacts on the diversity of arthropods in urban green spaces were preliminarily clarified.It will provide references for promoting the protection of biodiversity in urban green spaces.
2024,43(6):171-181
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.016
Abstract:
In recent years， there has been a shift in the approach to using grey infrastructure for rainwater and flood management， and the rainwater and flood regulation and storage function from the perspective of blue-green synergy has begun to be emphasized. To explore the reduction effect of various green space regulation methods on rainfall runoff， taking the South Lake catchment zone of Wuhan City as the research object， this paper simulates the changes in the total annual runoff control rate， peak flow and peak time under the sponge green space renovation measures based on the SWMM （storm water management model）， revealing the effect of green space on reducing rainwater runoff in the urban catchment zone from the perspective of blue-green synergy. The results show that： the transformation of concave green space with a scale of 20%-30% for urban catchment zones can achieve the sponge city construction goal of an annual runoff control rate of 65%.Among different sponge green space transformation measures， there is no significant difference in the effect of complex concave-down green space （with aquifer and lower pipe） and simple concave-down green space （without aquifer and lower pipe） on a single rainfall event. However， the performance of complex concave green space will be more significant for long-term and multi rainfall situations.
In recent years， there has been a shift in the approach to using grey infrastructure for rainwater and flood management， and the rainwater and flood regulation and storage function from the perspective of blue-green synergy has begun to be emphasized. To explore the reduction effect of various green space regulation methods on rainfall runoff， taking the South Lake catchment zone of Wuhan City as the research object， this paper simulates the changes in the total annual runoff control rate， peak flow and peak time under the sponge green space renovation measures based on the SWMM （storm water management model）， revealing the effect of green space on reducing rainwater runoff in the urban catchment zone from the perspective of blue-green synergy. The results show that： the transformation of concave green space with a scale of 20%-30% for urban catchment zones can achieve the sponge city construction goal of an annual runoff control rate of 65%.Among different sponge green space transformation measures， there is no significant difference in the effect of complex concave-down green space （with aquifer and lower pipe） and simple concave-down green space （without aquifer and lower pipe） on a single rainfall event. However， the performance of complex concave green space will be more significant for long-term and multi rainfall situations.
2024,43(6):182-190
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.017
Abstract:
Under the macro background of territorial space governance and green development， although the ecological restoration work for open-pit production mines has been widely carried out， the comprehensive research on exploring the multi-way utilization mode and the construction of sustainable landscape mode is still insufficient. This study aims to explore the typical ecological restoration landscape construction model adapted under the green development goal of open-pit production mines. Through systematically combing the research progress in the field of ecological restoration， combined with text analysis， field research and inductive research methods， such as production， life， ecology， from the perspective of three function depth fusion， put forward the ecological restoration of open production mine and sustainable utilization of the combination of three representative new landscape pattern： cultural leisure utilization mode， business industry utilization mode and agriculture and forestry production utilization mode. The core concept， unique points and relevant successful cases at home and abroad are elaborated in detail， aiming to provide theoretical support and application reference for subsequent practice. At the same time， in Huangshi City Tongshankou Mine， for example， try to put forward for the mine green development and transformation utilization strategy suggestions： ecological restoration process effectively into local characteristics， promote the diversified economic development and sustainable use of landscape， for similar mine ecological restoration and sustainable development path to provide useful reference and reference.
Under the macro background of territorial space governance and green development， although the ecological restoration work for open-pit production mines has been widely carried out， the comprehensive research on exploring the multi-way utilization mode and the construction of sustainable landscape mode is still insufficient. This study aims to explore the typical ecological restoration landscape construction model adapted under the green development goal of open-pit production mines. Through systematically combing the research progress in the field of ecological restoration， combined with text analysis， field research and inductive research methods， such as production， life， ecology， from the perspective of three function depth fusion， put forward the ecological restoration of open production mine and sustainable utilization of the combination of three representative new landscape pattern： cultural leisure utilization mode， business industry utilization mode and agriculture and forestry production utilization mode. The core concept， unique points and relevant successful cases at home and abroad are elaborated in detail， aiming to provide theoretical support and application reference for subsequent practice. At the same time， in Huangshi City Tongshankou Mine， for example， try to put forward for the mine green development and transformation utilization strategy suggestions： ecological restoration process effectively into local characteristics， promote the diversified economic development and sustainable use of landscape， for similar mine ecological restoration and sustainable development path to provide useful reference and reference.
2024,43(6):191-200
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.018
Abstract:
Bulk sampling was conducted on the fiber （10 days after anthesis） of interspecific F1 hybrids and parents of upland cotton to study the heterosis in fibers of interspecific F1 hybrids in terms of phenotype and genetics and analyze the reasons for the unclear heterosis in traits of yield. Transcriptomics was used to analyze the significant differences in transcription levels between samples. Bioinformatics was used to identify the significant differences in metabolic pathways and key genes between samples. The results showed that the F1 hybrid had fewer long fiber cells and the surface of the seed was covered by green fuzz. A total of 1 128 upregulated genes and 678 downregulated genes were identified in the transcriptome data of fiber between parents of upland cotton and interspecific F1 hybrids. The results of analyzing gene enrichment showed that the differential expression genes （DEGs） were mainly enriched in the biosynthesis of phenylpropane and biosynthesis pathways of flavonoid. The results of parental allele-specific expression analysis of DEGs showed that the allele of fiber in interspecific F1 hybrids tended to be expressed in sea- island cotton， among which the dihydroflavonol-3 '，5' - hydroxylase （F3'5'H） genes in the metabolic pathway of flavonoid in interspecific F1 hybrids only expressed the alleles of sea-island cotton. Overall， the traits of fiber yield in the interspecific F1 hybrids between sea-island cotton and upland cotton had negative heterosis and significant green and short fuzz in the fibers， which may be related to the secondary metabolites produced by the biosynthesis of phenylpropane and flavonoid. It is indicated that the heterosis and key metabolic pathways and genes of fibers in the interspecific F1 hybrids between upland cotton and sea-island cotton are investigated at the transcription level. The relationship between phenotypic traits and transcription and the relationship between transcription and metabolic synthesis are established.
Bulk sampling was conducted on the fiber （10 days after anthesis） of interspecific F1 hybrids and parents of upland cotton to study the heterosis in fibers of interspecific F1 hybrids in terms of phenotype and genetics and analyze the reasons for the unclear heterosis in traits of yield. Transcriptomics was used to analyze the significant differences in transcription levels between samples. Bioinformatics was used to identify the significant differences in metabolic pathways and key genes between samples. The results showed that the F1 hybrid had fewer long fiber cells and the surface of the seed was covered by green fuzz. A total of 1 128 upregulated genes and 678 downregulated genes were identified in the transcriptome data of fiber between parents of upland cotton and interspecific F1 hybrids. The results of analyzing gene enrichment showed that the differential expression genes （DEGs） were mainly enriched in the biosynthesis of phenylpropane and biosynthesis pathways of flavonoid. The results of parental allele-specific expression analysis of DEGs showed that the allele of fiber in interspecific F1 hybrids tended to be expressed in sea- island cotton， among which the dihydroflavonol-3 '，5' - hydroxylase （F3'5'H） genes in the metabolic pathway of flavonoid in interspecific F1 hybrids only expressed the alleles of sea-island cotton. Overall， the traits of fiber yield in the interspecific F1 hybrids between sea-island cotton and upland cotton had negative heterosis and significant green and short fuzz in the fibers， which may be related to the secondary metabolites produced by the biosynthesis of phenylpropane and flavonoid. It is indicated that the heterosis and key metabolic pathways and genes of fibers in the interspecific F1 hybrids between upland cotton and sea-island cotton are investigated at the transcription level. The relationship between phenotypic traits and transcription and the relationship between transcription and metabolic synthesis are established.
2024,43(6):201-209
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.019
Abstract:
The early-maturing cotton cultivar Huamian 3097 was used to study the rational application dosage of nitrogen for the direct seeding cotton after harvesting rapeseed oil in the cotton area of the Yangtze River Basin based on the concept of “increasing yield without increasing input”. Field experiments were conducted in 2022 and 2023 to investigate the effects of six application dosages of nitrogen including N180 （180 kg/hm2）， N210 （210 kg/hm2）， N240 （240 kg/hm2）， N270 （270 kg/hm2）， N300 （300 kg/hm2）， and N330 （330 kg/hm2） on the growth and development， photosynthetic characteristics， and yield of cotton. The results showed that the yield of cotton under N270 and N300 was comparable， but higher than that under N180 and N330.The two-year average yield of cotton seed and the number of bolls per unit area under N270 increased by 7.0% and 5.4%， 24.9% and 21.6% compared to that under N180 and N330， respectively. There was no difference in plant height， number of fruit branches， height of the first fruit branch， number of green leaves， and number of nodes between treatments. The light transmittance of cotton canopy decreased with the process of growth and the increase of application dosage of nitrogen. The light transmittance of cotton canopy within the canopy height of 30-50 cm and the cotton row of 20 cm under N270 was 23.9% higher than that under N330， 10.0% lower than that under N180， and comparable to that under N300.The net photosynthetic rate， transpiration rate， and stomatal conductance under N270 （N300） was higher than that under N180 and N330. The concentration of intercellular CO2 under N270 was lower than that under N180 and N330. It is indicated that applying 270 kg/hm2 nitrogen fertilizer to direct-seeding cotton after harvesting rapeseed oil is conducive to the growth and development of cotton， can increase the number of bolls per unit area and improve light transmission of canopy to enhance photosynthetic performance， and thus can achieve a higher yield.
The early-maturing cotton cultivar Huamian 3097 was used to study the rational application dosage of nitrogen for the direct seeding cotton after harvesting rapeseed oil in the cotton area of the Yangtze River Basin based on the concept of “increasing yield without increasing input”. Field experiments were conducted in 2022 and 2023 to investigate the effects of six application dosages of nitrogen including N180 （180 kg/hm2）， N210 （210 kg/hm2）， N240 （240 kg/hm2）， N270 （270 kg/hm2）， N300 （300 kg/hm2）， and N330 （330 kg/hm2） on the growth and development， photosynthetic characteristics， and yield of cotton. The results showed that the yield of cotton under N270 and N300 was comparable， but higher than that under N180 and N330.The two-year average yield of cotton seed and the number of bolls per unit area under N270 increased by 7.0% and 5.4%， 24.9% and 21.6% compared to that under N180 and N330， respectively. There was no difference in plant height， number of fruit branches， height of the first fruit branch， number of green leaves， and number of nodes between treatments. The light transmittance of cotton canopy decreased with the process of growth and the increase of application dosage of nitrogen. The light transmittance of cotton canopy within the canopy height of 30-50 cm and the cotton row of 20 cm under N270 was 23.9% higher than that under N330， 10.0% lower than that under N180， and comparable to that under N300.The net photosynthetic rate， transpiration rate， and stomatal conductance under N270 （N300） was higher than that under N180 and N330. The concentration of intercellular CO2 under N270 was lower than that under N180 and N330. It is indicated that applying 270 kg/hm2 nitrogen fertilizer to direct-seeding cotton after harvesting rapeseed oil is conducive to the growth and development of cotton， can increase the number of bolls per unit area and improve light transmission of canopy to enhance photosynthetic performance， and thus can achieve a higher yield.
2024,43(6):210-218
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.020
Abstract:
The 17-year-old forest of Caragana korshinskii in Damao Banner， Baotou City， Inner Mongolia was used to study the rule of changes in the configuration of fine root and the nutrients in soil of Caragana korshinskii under different stumping modes. The changes in the configuration of fine root and the nutrients in soil of artificial forests of Caragana korshinskii under treatments of stumping with 0 cm， 10 cm， and 20 cm and non-stumping （CK）. The results showed that the content of soil organic matter （SOM）， available nitrogen （AN）， available phosphorus （AP）， and available potassium （AK） in soil was the highest in the mode of stumping with 10 cm. The fine roots under different stumping modes had a typical fishtail-shaped branching structure， and the mode of stumping with 10 cm effectively improved the root branching structure and enhanced the growth of secondary branches. The total root length， specific root length， tissue density， and the content of dry matter in fine roots of Caragana korshinskii all were the best under the mode of stumping with 10 cm. The results of comprehensive analysis of membership function showed that the decreasing order was stumping with 10 cm （0.58）>stumping with 0 cm （0.46）>stumping with 20 cm （0.44）>no stubble （0.42）. It is indicated that the mode of stumping with 10 cm has the best effect on the regeneration and rejuvenation of Caragana korshinskii， which is conducive to promoting the conservation of soil and water and the sustainable development of the ecological environment in ecologically fragile areas.
The 17-year-old forest of Caragana korshinskii in Damao Banner， Baotou City， Inner Mongolia was used to study the rule of changes in the configuration of fine root and the nutrients in soil of Caragana korshinskii under different stumping modes. The changes in the configuration of fine root and the nutrients in soil of artificial forests of Caragana korshinskii under treatments of stumping with 0 cm， 10 cm， and 20 cm and non-stumping （CK）. The results showed that the content of soil organic matter （SOM）， available nitrogen （AN）， available phosphorus （AP）， and available potassium （AK） in soil was the highest in the mode of stumping with 10 cm. The fine roots under different stumping modes had a typical fishtail-shaped branching structure， and the mode of stumping with 10 cm effectively improved the root branching structure and enhanced the growth of secondary branches. The total root length， specific root length， tissue density， and the content of dry matter in fine roots of Caragana korshinskii all were the best under the mode of stumping with 10 cm. The results of comprehensive analysis of membership function showed that the decreasing order was stumping with 10 cm （0.58）>stumping with 0 cm （0.46）>stumping with 20 cm （0.44）>no stubble （0.42）. It is indicated that the mode of stumping with 10 cm has the best effect on the regeneration and rejuvenation of Caragana korshinskii， which is conducive to promoting the conservation of soil and water and the sustainable development of the ecological environment in ecologically fragile areas.
2024,43(6):219-228
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.021
Abstract:
Microplastics are widely present in soil， and the problem of microplastic pollution in soil has been considered during recent years. Three typical farmland soils including the paddy soil， the red soil and the fluvo-aquic soil were used to conduct indoor incubation experiments for 70 days to study the effects of microplastic pollution on the mineralization of organic carbon in soil under rice straw returning. 4 treatments including the control （CK）， addition of microplastics （polyethylene， PE）， addition of rice straw （RS）， addition of microplastics and rice straw （RS-PE） were set for each type of soil. The physical and chemical properties， the emission of CO2， the content of soluble organic carbon （SOC） and microbial biomass carbon （MBC） in each soil treated were measured. The results showed that the cumulative emission of CO2 from three types of soils within 70 days under the PE and RS-PE treatment was in the order of fluvo-aquic soil>paddy soil>red soil. Compared with CK， the cumulative emission of CO2 from three types of soils significantly increased after RS treatment， and the cumulative emission of CO2 from the red soil and fluvo-aquic soil significantly increased after PE treatment. Adding PE and RS increased the content of SOC and MBC in three types of soils， promoting the mineralization of organic carbon in soil. The E2/E3 value in three types of soils was in the order of paddy soil>red soil>fluvo-aquic soil. The addition of PE and RS increased the average relative molecular weight， aromaticity， and hydrophobicity of SOC in soil. The mineralization of organic carbon in three types of soils was significantly and negatively correlated with the average relative molecular weight of SOC （E2/E3）， and the mineralization of organic carbon in paddy and fluvo-aquic soil was significantly and positively correlated with the aromaticity （SUVA254） and hydrophobicity （SUVA260） of SOC. It is indicated that t the addition of microplastics and rice straw significantly affect the mineralization of organic carbon in soil.
Microplastics are widely present in soil， and the problem of microplastic pollution in soil has been considered during recent years. Three typical farmland soils including the paddy soil， the red soil and the fluvo-aquic soil were used to conduct indoor incubation experiments for 70 days to study the effects of microplastic pollution on the mineralization of organic carbon in soil under rice straw returning. 4 treatments including the control （CK）， addition of microplastics （polyethylene， PE）， addition of rice straw （RS）， addition of microplastics and rice straw （RS-PE） were set for each type of soil. The physical and chemical properties， the emission of CO2， the content of soluble organic carbon （SOC） and microbial biomass carbon （MBC） in each soil treated were measured. The results showed that the cumulative emission of CO2 from three types of soils within 70 days under the PE and RS-PE treatment was in the order of fluvo-aquic soil>paddy soil>red soil. Compared with CK， the cumulative emission of CO2 from three types of soils significantly increased after RS treatment， and the cumulative emission of CO2 from the red soil and fluvo-aquic soil significantly increased after PE treatment. Adding PE and RS increased the content of SOC and MBC in three types of soils， promoting the mineralization of organic carbon in soil. The E2/E3 value in three types of soils was in the order of paddy soil>red soil>fluvo-aquic soil. The addition of PE and RS increased the average relative molecular weight， aromaticity， and hydrophobicity of SOC in soil. The mineralization of organic carbon in three types of soils was significantly and negatively correlated with the average relative molecular weight of SOC （E2/E3）， and the mineralization of organic carbon in paddy and fluvo-aquic soil was significantly and positively correlated with the aromaticity （SUVA254） and hydrophobicity （SUVA260） of SOC. It is indicated that t the addition of microplastics and rice straw significantly affect the mineralization of organic carbon in soil.
2024,43(6):229-239
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.022
Abstract:
In order to identify the species of pathogenic fungi responsible for a novel soybean root rot in Guangdong， understand their biological characteristics， and screen effective fungicides to control the disease， the pathogenic fungi were isolated from the roots and stem bases of infected soybean plants using a tissue isolation method.The fungi were identified based on their morphology and through a combined phylogenetic analysis of 3 genes （rDNA-ITS， TEF-1α， and RPB2）.Subsequently， the isolated pathogenic fungi were inoculated into the roots and stem bases of the original soybean cultivar Guixia No.2， either alone or in combination， to determine their pathogenicity.The effects of various media， temperatures， carbon and nitrogen sources， pH， light and fungicides on mycelial growth， as well as the lethal temperatures of the pathogens’ conidia were measured.The results showed that two fungal strains with different characteristics were isolated from the roots and stem bases of infected soybean plants， identified as Fusarium neocosmosporiellum and F. falciforme， respectively.The later was first reported in soybeans in Guangdong， China.Inoculation experiments showed that both fungal strains， whether individually or in combination， could cause symptoms similar to those of soybean root rot disease observed in the field.F. neocosmosporiellum exhibited the fastest growth at 28 ?C and pH 7， effectively using a variety of carbon and nitrogen sources， with lactose and peptone identified as the most effective carbon and nitrogen sources， respectively.The lethal temperature for conida was 51 ?C for 10 min.In contrast， F. falciforme showed the highest growth rate at 25 ?C and pH 7， with a strong capacity for using carbon and nitrogen sources.Lactose， sucrose， and maltose were the most effective carbon sources， while peptone was the optimal nitrogen source.The lethal temperature for conidia was 54 ?C for 10 min.Different light treatments did not affect the mycelial growth of either strain.The fungicide prochloraz exhibited the strongest inhibitory effect on both strains.In summary， the pathogenic fungi responseble for the novel soybean root rot disease in Guangdong were F.neocosmosporiellum and F. falciforme.These two fungi demonstrate strong environmental adaptability and sensitivity to prochloraz， making it the preferred choice for controlling the novel soybean root rot disease.
In order to identify the species of pathogenic fungi responsible for a novel soybean root rot in Guangdong， understand their biological characteristics， and screen effective fungicides to control the disease， the pathogenic fungi were isolated from the roots and stem bases of infected soybean plants using a tissue isolation method.The fungi were identified based on their morphology and through a combined phylogenetic analysis of 3 genes （rDNA-ITS， TEF-1α， and RPB2）.Subsequently， the isolated pathogenic fungi were inoculated into the roots and stem bases of the original soybean cultivar Guixia No.2， either alone or in combination， to determine their pathogenicity.The effects of various media， temperatures， carbon and nitrogen sources， pH， light and fungicides on mycelial growth， as well as the lethal temperatures of the pathogens’ conidia were measured.The results showed that two fungal strains with different characteristics were isolated from the roots and stem bases of infected soybean plants， identified as Fusarium neocosmosporiellum and F. falciforme， respectively.The later was first reported in soybeans in Guangdong， China.Inoculation experiments showed that both fungal strains， whether individually or in combination， could cause symptoms similar to those of soybean root rot disease observed in the field.F. neocosmosporiellum exhibited the fastest growth at 28 ?C and pH 7， effectively using a variety of carbon and nitrogen sources， with lactose and peptone identified as the most effective carbon and nitrogen sources， respectively.The lethal temperature for conida was 51 ?C for 10 min.In contrast， F. falciforme showed the highest growth rate at 25 ?C and pH 7， with a strong capacity for using carbon and nitrogen sources.Lactose， sucrose， and maltose were the most effective carbon sources， while peptone was the optimal nitrogen source.The lethal temperature for conidia was 54 ?C for 10 min.Different light treatments did not affect the mycelial growth of either strain.The fungicide prochloraz exhibited the strongest inhibitory effect on both strains.In summary， the pathogenic fungi responseble for the novel soybean root rot disease in Guangdong were F.neocosmosporiellum and F. falciforme.These two fungi demonstrate strong environmental adaptability and sensitivity to prochloraz， making it the preferred choice for controlling the novel soybean root rot disease.
2024,43(6):240-252
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.023
Abstract:
Jujube witches’ broom disease is a significant threat to jujube trees.To reveal the key biological pathways associated with disease resistance in jujube germplasm in response to phytoplasma infection， a graft-inoculation method was used to evaluate the resistance of 324 jujube germplasm resources to this disease.The study utilized disease-resistant germplasms ‘QS10’，‘UU12’，‘EQ15’ and the susceptible germplasms ‘Zhongyangmuzao’，‘Hupingzao’，‘Luzhao 5’ as materials.The phytoplasma content in leaf tissues was measured at 90 days and 120 days post-infection，and transcriptome sequencing was conducted to elucidate the differential responses.The results showed that the concentration of phytoplasma in resistant germplasm was low and gradually decreased after grafting，while the concentration of phytoplasma in susceptible germplasm was higher and gradually increased over time.The DEGs of both resistant and susceptible germplasm were significantly enriched in pathways such as plant-pathogen interaction，plant hormone signal transduction，and biosynthesis of secondary metabolites.Notable differences were observed in the expression of genes related to peroxisome，photosynthetic pathway and flavonoid biosynthesis pathway.WGCNA analysis revealed that core genes such as lipid phosphatase，RNA editing factor MORF 3，LysM domain receptor-like kinase，and serine/threonine protein kinase sty13-like were associated with resistant germplasm.Research indicated that in response to phytoplasma invasion，the differential expression of genes involved in plant-pathogen interaction，synthesis of secondary metabolites，plant hormone signal transduction，and MAPK signaling pathways may contribute to the differential phenotypes observed between resistant and susceptible germplasms.The peroxisome-related genes are upregulated in disease-resistant germplasm，while photosynthetic genes are less affected by phytoplasma invasion，which may contribute to the normal progression of energy metabolism and redox balance of resistant germplasm，thereby enhancing its disease resistance.Additionally，secondary metabolites such as flavonoids and terpenes may play a role in eliminating the damage caused by active oxygen.
Jujube witches’ broom disease is a significant threat to jujube trees.To reveal the key biological pathways associated with disease resistance in jujube germplasm in response to phytoplasma infection， a graft-inoculation method was used to evaluate the resistance of 324 jujube germplasm resources to this disease.The study utilized disease-resistant germplasms ‘QS10’，‘UU12’，‘EQ15’ and the susceptible germplasms ‘Zhongyangmuzao’，‘Hupingzao’，‘Luzhao 5’ as materials.The phytoplasma content in leaf tissues was measured at 90 days and 120 days post-infection，and transcriptome sequencing was conducted to elucidate the differential responses.The results showed that the concentration of phytoplasma in resistant germplasm was low and gradually decreased after grafting，while the concentration of phytoplasma in susceptible germplasm was higher and gradually increased over time.The DEGs of both resistant and susceptible germplasm were significantly enriched in pathways such as plant-pathogen interaction，plant hormone signal transduction，and biosynthesis of secondary metabolites.Notable differences were observed in the expression of genes related to peroxisome，photosynthetic pathway and flavonoid biosynthesis pathway.WGCNA analysis revealed that core genes such as lipid phosphatase，RNA editing factor MORF 3，LysM domain receptor-like kinase，and serine/threonine protein kinase sty13-like were associated with resistant germplasm.Research indicated that in response to phytoplasma invasion，the differential expression of genes involved in plant-pathogen interaction，synthesis of secondary metabolites，plant hormone signal transduction，and MAPK signaling pathways may contribute to the differential phenotypes observed between resistant and susceptible germplasms.The peroxisome-related genes are upregulated in disease-resistant germplasm，while photosynthetic genes are less affected by phytoplasma invasion，which may contribute to the normal progression of energy metabolism and redox balance of resistant germplasm，thereby enhancing its disease resistance.Additionally，secondary metabolites such as flavonoids and terpenes may play a role in eliminating the damage caused by active oxygen.
2024,43(6):253-260
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.024
Abstract:
Heart rot is a newly identified pitaya disease， which affects the yield and commercial value of the fruit， with an incidence rate of 10% in autumn and winter seasons.In order to effectively prevent and control heart rot in pitaya fruit， we used strains isolated from diseased fruit in the field as materials.We conducted ITS gene sequence analysis， as well as in vivo inoculation methods in both indoor and field settings， to identify the pathogen and determine the initial point of infestation and its biological properties.The results showed that the the symptoms of pitaya heart rot disease in the field include yellowing and dropping of some young fruits， premature reddening of young fruit skin， and brown rot of the fruit flesh.The pathogenic strain was identified as Gilbertella persicaria.The initial infection point of the pathogen is the stigma of the pistil， and the sporangiospores can colonize the stigmas of female either directly or indirectly through pollen， resulting in heart rot during pollination， fertilization and fruit development.The optimal growth temperature and pH value for G. persicaria were 30 ℃ and pH 5， respectively， while light exposure could inhibit the sporulation of the fungus.These results indicate that G.persicaria could cause pitaya heart rot by infecting the stigmas of female.To mitigate the damage of G. persicaria to pitaya fruits， it is recommended to promptly remove petals after pollination or apply fungicide treatments， thus decreasing the initial inoculum load.
Heart rot is a newly identified pitaya disease， which affects the yield and commercial value of the fruit， with an incidence rate of 10% in autumn and winter seasons.In order to effectively prevent and control heart rot in pitaya fruit， we used strains isolated from diseased fruit in the field as materials.We conducted ITS gene sequence analysis， as well as in vivo inoculation methods in both indoor and field settings， to identify the pathogen and determine the initial point of infestation and its biological properties.The results showed that the the symptoms of pitaya heart rot disease in the field include yellowing and dropping of some young fruits， premature reddening of young fruit skin， and brown rot of the fruit flesh.The pathogenic strain was identified as Gilbertella persicaria.The initial infection point of the pathogen is the stigma of the pistil， and the sporangiospores can colonize the stigmas of female either directly or indirectly through pollen， resulting in heart rot during pollination， fertilization and fruit development.The optimal growth temperature and pH value for G. persicaria were 30 ℃ and pH 5， respectively， while light exposure could inhibit the sporulation of the fungus.These results indicate that G.persicaria could cause pitaya heart rot by infecting the stigmas of female.To mitigate the damage of G. persicaria to pitaya fruits， it is recommended to promptly remove petals after pollination or apply fungicide treatments， thus decreasing the initial inoculum load.
2024,43(6):261-269
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.025
Abstract:
The colorimeter was used to measure the values of L* （brightness），a* （redness-greenness） and b* （yellowness-blueness） in petals of marigold （Tagetes erecta） to establish a rapid method for determining the lutein content in petals of marigold.The color coefficients including a*/b*，（a*/b*）2，chroma value，hue value and shade value were calculated.UV-spectrophotometry combined with HPLC method was used to determine the lutein content in petals.The correlation between the lutein content and the color coefficients was analyzed.The regression equation was established and confirmed.The results showed that the lutein content in petals of marigold was significantly correlated with a*、a*/b*、（a*/b*）2，hue value and shade value.The regression equation between the lutein content and a* value constructed by cubic function model had the highest degree of fitness，and there was no significant difference between the predicted value and the measured value of the lutein content.It is indicated that the cubic function model based on a* value can quickly and non-destructively predict the content of lutein petals of marigold.
The colorimeter was used to measure the values of L* （brightness），a* （redness-greenness） and b* （yellowness-blueness） in petals of marigold （Tagetes erecta） to establish a rapid method for determining the lutein content in petals of marigold.The color coefficients including a*/b*，（a*/b*）2，chroma value，hue value and shade value were calculated.UV-spectrophotometry combined with HPLC method was used to determine the lutein content in petals.The correlation between the lutein content and the color coefficients was analyzed.The regression equation was established and confirmed.The results showed that the lutein content in petals of marigold was significantly correlated with a*、a*/b*、（a*/b*）2，hue value and shade value.The regression equation between the lutein content and a* value constructed by cubic function model had the highest degree of fitness，and there was no significant difference between the predicted value and the measured value of the lutein content.It is indicated that the cubic function model based on a* value can quickly and non-destructively predict the content of lutein petals of marigold.
2024,43(6):270-281
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.026
Abstract:
Sunlight withering treatment was conducted on different tea varieties including black tea， green tea and red green mixed varieties， and different tenderness of fresh leaf including one bud with one leaf， one bud with two leaves to study the effects of sunlight withering on the quality of processed black tea with different fresh leaf tenderness and tea plant varieties. The results showed that the effects of sunlight withering on the quality of processed black tea of different fresh leaf tenderness and tea plant cultivars were different. There was less damage to the leaves and the content of tea polyphenols and amino acids respectively decreased by 1%, 6%, 8% and 11%, 19%, 14% during the withering process of the tenderness of fresh leaf including one bud with two or three leaves and below. The content of soluble sugar increased more， increasing by 15%， 13% and 11%， respectively. The content of theaflavins was relatively high， with a significant increase of 32% in black tea with one bud with three leaves and 10% with one bud with four or five leaves. It is indicated that sunlight withering has a significant effect on treating the tenderness of fresh leaf including one bud with two or three leaves and below， and is suitable for tea tree varieties with weaker floral and fruity aromas. It is not necessary to perform sunlight withering on varieties of processed black tea with strong floral and fruity aromas. Albino and purple varieties are not suitable for sunlight withering.
Sunlight withering treatment was conducted on different tea varieties including black tea， green tea and red green mixed varieties， and different tenderness of fresh leaf including one bud with one leaf， one bud with two leaves to study the effects of sunlight withering on the quality of processed black tea with different fresh leaf tenderness and tea plant varieties. The results showed that the effects of sunlight withering on the quality of processed black tea of different fresh leaf tenderness and tea plant cultivars were different. There was less damage to the leaves and the content of tea polyphenols and amino acids respectively decreased by 1%, 6%, 8% and 11%, 19%, 14% during the withering process of the tenderness of fresh leaf including one bud with two or three leaves and below. The content of soluble sugar increased more， increasing by 15%， 13% and 11%， respectively. The content of theaflavins was relatively high， with a significant increase of 32% in black tea with one bud with three leaves and 10% with one bud with four or five leaves. It is indicated that sunlight withering has a significant effect on treating the tenderness of fresh leaf including one bud with two or three leaves and below， and is suitable for tea tree varieties with weaker floral and fruity aromas. It is not necessary to perform sunlight withering on varieties of processed black tea with strong floral and fruity aromas. Albino and purple varieties are not suitable for sunlight withering.
2024,43(6):282-288
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.027
Abstract:
In order to explore the effective protective substances for freeze-drying Mycoplasma bovis （M. bovis）， this study employed a four-factor， four-level orthogonal design experiment alongside a single-factor experiment. The effects of skim milk， sucrose， mannitol， glucan， trehalose， urea， BSA， lysine， and other substances on the survival rate of M. bovis were detected by measuring the number of the live M. bovis HB150 post freeze-drying and the optimal concentrations and ratios of the different protective agents were ultimately established. The ratios of the main and auxiliary components of the freeze-drying protectants were determined through orthogonal design experiments， and the final ratios of the lyophilized protectants were as follows： 15% skimmed milk， 4.0% sucrose， 4.0% mannitol， 3.0% glucan， 2.0% alginate， 1.5% urea， 1.0% BSA， and 0.3% lysine. When freeze-drying at -40 ℃ and 12 Pa for 20 h， this formulation maintained the highest activity rate of M. bovis， reaching （55.2±2.1）%. The results indicated that the selected dynamic dry protectants exhibited a strong protective effect and could be effectively applied in the actual freeze-drying process of M. bovis.
In order to explore the effective protective substances for freeze-drying Mycoplasma bovis （M. bovis）， this study employed a four-factor， four-level orthogonal design experiment alongside a single-factor experiment. The effects of skim milk， sucrose， mannitol， glucan， trehalose， urea， BSA， lysine， and other substances on the survival rate of M. bovis were detected by measuring the number of the live M. bovis HB150 post freeze-drying and the optimal concentrations and ratios of the different protective agents were ultimately established. The ratios of the main and auxiliary components of the freeze-drying protectants were determined through orthogonal design experiments， and the final ratios of the lyophilized protectants were as follows： 15% skimmed milk， 4.0% sucrose， 4.0% mannitol， 3.0% glucan， 2.0% alginate， 1.5% urea， 1.0% BSA， and 0.3% lysine. When freeze-drying at -40 ℃ and 12 Pa for 20 h， this formulation maintained the highest activity rate of M. bovis， reaching （55.2±2.1）%. The results indicated that the selected dynamic dry protectants exhibited a strong protective effect and could be effectively applied in the actual freeze-drying process of M. bovis.
2024,43(6):289-296
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.028
Abstract:
To explore the effect of N-acetyltransferase（NAT） on the pathogenicity of Streptococcus agalacae， the nat gene deletion strain Δnat was constructed by homologous recombination in the background of a wild strain HN016. The growth curve， morphology， cell adhesion， invasion， antiphagocytosis， whole blood survival and pathogenicity of wild strain and Δnat strain were compared. The results showed that the hemolytic capacity of Δnat decreased， and the loss of nat decreased the adhesion and invasion of S. agalactiae to tilapia brain cells and increased the bacterial susceptibility to blood killing and phagocytosis. The result of challenge experiment of tilapia showed that the lethality of Δnat （2×108 CFU/fish， the mortality rate was 36%） was significantly lower than that of wild strain HN016 （2×108 CFU/fish， the mortality rate was 85%）. And the bacterial loads of Δnat were much less than that of HN016 in blood， spleen and brain tissue at 12 h post infection. This study firstly reports that NAT plays an important role in S. agalactiae resistance to host blood and phagocyte clearance， and assists in the bacterial invasion and colonization of tilapia tissues.
To explore the effect of N-acetyltransferase（NAT） on the pathogenicity of Streptococcus agalacae， the nat gene deletion strain Δnat was constructed by homologous recombination in the background of a wild strain HN016. The growth curve， morphology， cell adhesion， invasion， antiphagocytosis， whole blood survival and pathogenicity of wild strain and Δnat strain were compared. The results showed that the hemolytic capacity of Δnat decreased， and the loss of nat decreased the adhesion and invasion of S. agalactiae to tilapia brain cells and increased the bacterial susceptibility to blood killing and phagocytosis. The result of challenge experiment of tilapia showed that the lethality of Δnat （2×108 CFU/fish， the mortality rate was 36%） was significantly lower than that of wild strain HN016 （2×108 CFU/fish， the mortality rate was 85%）. And the bacterial loads of Δnat were much less than that of HN016 in blood， spleen and brain tissue at 12 h post infection. This study firstly reports that NAT plays an important role in S. agalactiae resistance to host blood and phagocyte clearance， and assists in the bacterial invasion and colonization of tilapia tissues.
2024,43(6):297-306
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.029
Abstract:
The residues of 19 pesticides in integrated rice and Procambarus clarkii breeding environments in Hubei Province were investigated， and the ecological risk and dietary risks associated with P. clarkii in paddy fields were assessed. The results showed that three pesticides， β-666， δ-666 and endrin， were detected in the water samples from 22 sites of rice and P. clarkii farming， but most of these residues were attributed to earlier environmental residues. Four types of pesticides were detected in P. clarkii samples， with one source linked to pesticide application on rice， and another related to the feed of P. clarkii. The order of dietary risk values for P. clarkii was hexachlorobenzene > HCHS > DDTs > pendimethalin， with the dietary intake risks ranging from 0.002% to 0.206%. Therefore， the levels of pesticide residues in the rice and P. clarkii breeding environments in Hubei Province are within a safe range， but the potential dietary risks associated with multi-route and long-term pesticide exposure to crawfish warrant ongoing attention.
The residues of 19 pesticides in integrated rice and Procambarus clarkii breeding environments in Hubei Province were investigated， and the ecological risk and dietary risks associated with P. clarkii in paddy fields were assessed. The results showed that three pesticides， β-666， δ-666 and endrin， were detected in the water samples from 22 sites of rice and P. clarkii farming， but most of these residues were attributed to earlier environmental residues. Four types of pesticides were detected in P. clarkii samples， with one source linked to pesticide application on rice， and another related to the feed of P. clarkii. The order of dietary risk values for P. clarkii was hexachlorobenzene > HCHS > DDTs > pendimethalin， with the dietary intake risks ranging from 0.002% to 0.206%. Therefore， the levels of pesticide residues in the rice and P. clarkii breeding environments in Hubei Province are within a safe range， but the potential dietary risks associated with multi-route and long-term pesticide exposure to crawfish warrant ongoing attention.
2024,43(6):307-315
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.030
Abstract:
Macrophage is an essential component of the innate immune system. However， Streptococcus agalactiae has the ability to survive within macrophage， allowing it to infiltrate the central nervous system. To elucidate the mechanisms underlying the survival of S. agalactiae within macrophages， we investigated the genome-wide transcriptional changes of S. agalactiae following phagocytosis by RAW264.7 and explored the metabolic pathways and genes associated with the intracellular survival of S. agalactiae. The S. agalactiae strain HN016 was co-incubated with RAW264.7 and the intracellular bacteria were subjected to transcriptome sequencing （RNA-seq）， gene ontology （GO）， and Kyoto encyclopedia of genes and genomes （KEGG） enrichment analysis. Additionlly， HN016 was incubated with primary tilapia macrophages in vitro and RNA from the intracellular bacteria were extracted. Quantitative real-time PCR （qPCR） was used to verify the expression of the target genes. The results showed that a total of 1 215 differentially expressed genes （DEGs）， including 869 up-regulated genes and 319 down-regulated genes， were screened， compared with the untreated group. DEGs were significantly enriched in all three Go terms： molecular function， biological process， and cellular component. KEGG enrichment analysis showed that the main enriched pathways were ABC transporter， ribosome， quorum sensing， and glycolysis/gluconeogenesis. Among the DEGs， 27 virulence-related genes were screened， including fbsA （+8.65）， sip （+6.28）， cylD （+4.93）， and cfb （-4.65）. qPCR was used to validate the RNA-seq results， and the agreement between two datasets demonstrated the reliability of the RNA-seq analysis. The transcript levels of surviving bacteria in primary macrophages of tilapia were similar to those in mouse macrophages. Based on these findings， it was hypothesized that the noxious environment within macrophage enhanced the signaling mechanisms， energy transport capacity， and metabolic capacity of secondary metabolites produced by macrophages， as well as the expression levels of virulence-related genes of S. agalactiae.
Macrophage is an essential component of the innate immune system. However， Streptococcus agalactiae has the ability to survive within macrophage， allowing it to infiltrate the central nervous system. To elucidate the mechanisms underlying the survival of S. agalactiae within macrophages， we investigated the genome-wide transcriptional changes of S. agalactiae following phagocytosis by RAW264.7 and explored the metabolic pathways and genes associated with the intracellular survival of S. agalactiae. The S. agalactiae strain HN016 was co-incubated with RAW264.7 and the intracellular bacteria were subjected to transcriptome sequencing （RNA-seq）， gene ontology （GO）， and Kyoto encyclopedia of genes and genomes （KEGG） enrichment analysis. Additionlly， HN016 was incubated with primary tilapia macrophages in vitro and RNA from the intracellular bacteria were extracted. Quantitative real-time PCR （qPCR） was used to verify the expression of the target genes. The results showed that a total of 1 215 differentially expressed genes （DEGs）， including 869 up-regulated genes and 319 down-regulated genes， were screened， compared with the untreated group. DEGs were significantly enriched in all three Go terms： molecular function， biological process， and cellular component. KEGG enrichment analysis showed that the main enriched pathways were ABC transporter， ribosome， quorum sensing， and glycolysis/gluconeogenesis. Among the DEGs， 27 virulence-related genes were screened， including fbsA （+8.65）， sip （+6.28）， cylD （+4.93）， and cfb （-4.65）. qPCR was used to validate the RNA-seq results， and the agreement between two datasets demonstrated the reliability of the RNA-seq analysis. The transcript levels of surviving bacteria in primary macrophages of tilapia were similar to those in mouse macrophages. Based on these findings， it was hypothesized that the noxious environment within macrophage enhanced the signaling mechanisms， energy transport capacity， and metabolic capacity of secondary metabolites produced by macrophages， as well as the expression levels of virulence-related genes of S. agalactiae.
2024,43(6):316-324
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.031
Abstract:
Hubei hybrid wolfberry was used to study its nutritional quality and anti-fatigue effect and compare with that of the commercially available northern wolfberry as the raw material of the thick pulp beverage. The effects of Hubei hybrid wolfberry drink on relieving physical fatigue were investigated by analyzing its nutritional quality and determining the exhaustion time of swimming with a load in mice. In the animal experiments， the content of liver glycogen（LG），muscle glycogen （MG），blood lactic acid（BLA），blood urea nitrogen （BUN），malondialdehyde （MDA）， superoxide dismutase （SOD），and glutathione reductase （GR） after exercise in mice after gavage of Hubei hybrid wolfberry thick pulp beverage at different dosage（4，8，12 mL/kg） were determined and compared with that of the blank group. The results showed that active substances including phenolics 175.44 μg/g， flavonoids 98.91 μg/g， proteins 1.90 mg/g， betaine 0.30 mg/mL， and Se 1.59 μg/kg in Hubei hybrid wolfberry thick pulp beverage were higher than that of commercially available wolfberry thick pulp beverage， and had better antioxidant activity. The results of animal experiments showed that the medium-dosage and high-dosage group（daily gavage at 8 and 12 mL/kg） of Hubei hybrid wolfberry thick pulp beverage effectively prolonged the exhaustion time of swimming with a load in mice， and both of them significantly improved the anti-fatigue effect on mice （P<0.05）， 1.66 times and 2.10 times more than that in the blank group. The high-dosage group（daily gavage at 12 mL/kg） was 1.32 times higher than that of the commercially available commercially available wolfberry thick pulp beverage group， and the difference was significant（P<0.05）. After exercise， the content of MG and LG of mice in the high dosage group of Hubei hybrid wolfberry thick pulp beverage increased by 47.03% and 116.22% compared to the blank group， and the content of BLA， BUN， and MDA significantly decreased （P<0.05）， and the activity of SOD and GR significantly increased （P<0.05）， indicating that Hubei hybrid wolfberry thick pulp beverage has better anti-fatigue effect. It will provide a scientific basis for mining the health effect of Hubei hybrid wolfberry and a new idea for developing functional foods for people with exercise fatigue.
Hubei hybrid wolfberry was used to study its nutritional quality and anti-fatigue effect and compare with that of the commercially available northern wolfberry as the raw material of the thick pulp beverage. The effects of Hubei hybrid wolfberry drink on relieving physical fatigue were investigated by analyzing its nutritional quality and determining the exhaustion time of swimming with a load in mice. In the animal experiments， the content of liver glycogen（LG），muscle glycogen （MG），blood lactic acid（BLA），blood urea nitrogen （BUN），malondialdehyde （MDA）， superoxide dismutase （SOD），and glutathione reductase （GR） after exercise in mice after gavage of Hubei hybrid wolfberry thick pulp beverage at different dosage（4，8，12 mL/kg） were determined and compared with that of the blank group. The results showed that active substances including phenolics 175.44 μg/g， flavonoids 98.91 μg/g， proteins 1.90 mg/g， betaine 0.30 mg/mL， and Se 1.59 μg/kg in Hubei hybrid wolfberry thick pulp beverage were higher than that of commercially available wolfberry thick pulp beverage， and had better antioxidant activity. The results of animal experiments showed that the medium-dosage and high-dosage group（daily gavage at 8 and 12 mL/kg） of Hubei hybrid wolfberry thick pulp beverage effectively prolonged the exhaustion time of swimming with a load in mice， and both of them significantly improved the anti-fatigue effect on mice （P<0.05）， 1.66 times and 2.10 times more than that in the blank group. The high-dosage group（daily gavage at 12 mL/kg） was 1.32 times higher than that of the commercially available commercially available wolfberry thick pulp beverage group， and the difference was significant（P<0.05）. After exercise， the content of MG and LG of mice in the high dosage group of Hubei hybrid wolfberry thick pulp beverage increased by 47.03% and 116.22% compared to the blank group， and the content of BLA， BUN， and MDA significantly decreased （P<0.05）， and the activity of SOD and GR significantly increased （P<0.05）， indicating that Hubei hybrid wolfberry thick pulp beverage has better anti-fatigue effect. It will provide a scientific basis for mining the health effect of Hubei hybrid wolfberry and a new idea for developing functional foods for people with exercise fatigue.
2024,43(6):325-332
, DOI: 10.13300/j.cnki.hnlkxb.2024.06.032
Abstract:
An orthogonal experiment with 4 factors and 3 levels was designed using models of operating including XP2020 and T16， types of pesticide including chlorfenapyr suspension， methomyl indoxacarb water emulsion， and cyanogen caulis EC and silicone adjuvant， volumes of application including 15 L/hm2， 22.5 L/hm2， and 30 L/hm2， and empty column as control to study the optimal operation mode of using agricultural unmanned aerial vehicles （UAVs） to prevent and control the corn borer. 9 collection areas of UAV droplet and investigation areas of prevention and control were set up in the field experiment， and high-gap operation areas of sprayer and blank area were set up as controls to comprehensively evaluate the deposition of droplet and the effect of prevention and control of corn borer under different modes of operation. The significance of each factor was analyzed in depth with Analysis of Variance （ANOVA）. The results showed that there was a positive correlation between the diameter of droplet volume in the experimental area and the amount of deposition under the current experimental conditions （R2=0.712， P<0.05）. The type of pesticide had a significant impact on the effect of prevention and control of corn borer （P<0.05）. The model of operating and the volume of pesticide applied within the range （15~30 L/ hm2） had no significant impact on the effect of prevention and control of corn borer. It is recommended to use T16 UAV in combination with cyanogen caulis EC and silicone adjuvant， with an application rate of 22.5 L/hm2 to prevent and control the corn borers taking into account various factors including the effect of prevention and control， the efficiency of operation， economic benefits， and the mitigation of risk. The effect of prevention and control on corn borer can reach 72% after 7 days of application. It will provide a reference for using agricultural UAVs to prevent and control the corn borer larvae and an important guidance for optimizing the application of pesticide and improving the utilization of pesticide.
An orthogonal experiment with 4 factors and 3 levels was designed using models of operating including XP2020 and T16， types of pesticide including chlorfenapyr suspension， methomyl indoxacarb water emulsion， and cyanogen caulis EC and silicone adjuvant， volumes of application including 15 L/hm2， 22.5 L/hm2， and 30 L/hm2， and empty column as control to study the optimal operation mode of using agricultural unmanned aerial vehicles （UAVs） to prevent and control the corn borer. 9 collection areas of UAV droplet and investigation areas of prevention and control were set up in the field experiment， and high-gap operation areas of sprayer and blank area were set up as controls to comprehensively evaluate the deposition of droplet and the effect of prevention and control of corn borer under different modes of operation. The significance of each factor was analyzed in depth with Analysis of Variance （ANOVA）. The results showed that there was a positive correlation between the diameter of droplet volume in the experimental area and the amount of deposition under the current experimental conditions （R2=0.712， P<0.05）. The type of pesticide had a significant impact on the effect of prevention and control of corn borer （P<0.05）. The model of operating and the volume of pesticide applied within the range （15~30 L/ hm2） had no significant impact on the effect of prevention and control of corn borer. It is recommended to use T16 UAV in combination with cyanogen caulis EC and silicone adjuvant， with an application rate of 22.5 L/hm2 to prevent and control the corn borers taking into account various factors including the effect of prevention and control， the efficiency of operation， economic benefits， and the mitigation of risk. The effect of prevention and control on corn borer can reach 72% after 7 days of application. It will provide a reference for using agricultural UAVs to prevent and control the corn borer larvae and an important guidance for optimizing the application of pesticide and improving the utilization of pesticide.
Display Method:
Abstract:
To investigate the effect of in the “rice-duck-crayfish” model(CDR) on soil fertility in paddy fields, the physical, chemical and biological properties of the soils were compared between CDR and the rice monoculture model(RM) by using field experiments and sampling tests and analysis after rice harvesting in 2022-2023. The soil fertility of the two models was comprehensively evaluated by combining the fuzzy comprehensive evaluation method and the simple linear scoring method. The results showed that soil microbial biomass nitrogen significantly decreased by 53.27% after 2 years of CDR; the soil organic matter, total nitrogen, available potassium and microbial biomass carbon showed an increasing trend, and the soil pH, available nitrogen, available phosphorus, acid phosphatase and alkaline phosphatase declined, but none of them showed a significant difference. Compared with RM, except for the microbial biomass nitrogen, other indicators showed different degrees of reduction. From the perspective of soil fertility, there was no significant difference between CDR and RM under 2-year planting and rearing conditions, but the soil fertility index of the paddy field in CDR showed an increasing trend, with an increase of 7.94%, while the soil fertility index decreased in RM, and the soil fertility index of CDR was 3.03% higher than that of RM in 2023. Therefore, there was no significant change in the soil fertility of paddy fields under CDR in two years.
To investigate the effect of in the “rice-duck-crayfish” model(CDR) on soil fertility in paddy fields, the physical, chemical and biological properties of the soils were compared between CDR and the rice monoculture model(RM) by using field experiments and sampling tests and analysis after rice harvesting in 2022-2023. The soil fertility of the two models was comprehensively evaluated by combining the fuzzy comprehensive evaluation method and the simple linear scoring method. The results showed that soil microbial biomass nitrogen significantly decreased by 53.27% after 2 years of CDR; the soil organic matter, total nitrogen, available potassium and microbial biomass carbon showed an increasing trend, and the soil pH, available nitrogen, available phosphorus, acid phosphatase and alkaline phosphatase declined, but none of them showed a significant difference. Compared with RM, except for the microbial biomass nitrogen, other indicators showed different degrees of reduction. From the perspective of soil fertility, there was no significant difference between CDR and RM under 2-year planting and rearing conditions, but the soil fertility index of the paddy field in CDR showed an increasing trend, with an increase of 7.94%, while the soil fertility index decreased in RM, and the soil fertility index of CDR was 3.03% higher than that of RM in 2023. Therefore, there was no significant change in the soil fertility of paddy fields under CDR in two years.
Abstract:
In order to explore the appropriate method of breaking and threshing of fresh lotus seedpods, and achieve high efficiency and low damage mechanical lotus seed dewatering. The space lotus was taken as the research object in this study. The moisture content, appearance characteristics and mechanical properties of lotus seedpods with different maturity were carried out, especially focusing on the mechanical properties under shear, tensile and puncture loading method. The damage law of lotus seedpod tissue under different loading conditions were compared and analyzed. The results showed that the moisture content of lotus seeds was the highest in the lotus seed tissue, while the moisture content of the lotus seed epidermis was the lowest. Moreover, as the moisture content decreased, the moisture content of the lotus seed epidermis decreased the most significantly. Comparing the milk ripening period and wax ripening period, the appearance of lotus pods and seeds are fuller during the fully ripe period, with gaps appearing between the seeds and tissues. The shear and tensile properties of the lotus seedpods epidermis were obviously anisotropic, and the external loading mode had a significant impact on the shear and tensile rupture force. With the increase of maturity, the transverse shear rupture force and axial tensile rupture force of the epidermis increased gradually, while the longitudinal shear rupture force and transverse tensile rupture force of the epidermis had no obvious change. The loading speed had no significant effect on the shear and tensile rupture force of the epidermis. The average tensile rupture force of fiber tissues was larger at ripening stage, and there was no significant difference between milk ripening stage and wax ripening stage, and the loading speed had no significant effect on the tensile rupture force. Epidermal puncture damage of lotus seedpod was not affected by epidermal anisotropy. With the increase of maturity, the puncture rupture force of lotus seedpod decreased gradually, while the rupture force of epidermal puncture increased gradually. With the increase of the diameter of the probe, the rupture force of surface puncture and epidermal puncture increased. The loading method had the greatest influence on the loading rupture force of the epidermis, followed by maturity, and the least was loading speed. Different maturity of lotus seed epidermis could achieve less damage under external load under longitudinal shear or transverse stretching, but its anisotropic characteristics make it not universal when designing the machine. After comprehensive analysis of the three loading method, the universal mode of breaking the lotus seedpod was determined, that was, the puncture loading was applied first to destroy the lotus seed, the damage was achieved with less destructive power, and then the tensile cracking force was applied to achieve the efficient tearing of the lotus seed. The above research will provide theoretical basis for the design of fresh lotus seed peeling and threshing machine.
In order to explore the appropriate method of breaking and threshing of fresh lotus seedpods, and achieve high efficiency and low damage mechanical lotus seed dewatering. The space lotus was taken as the research object in this study. The moisture content, appearance characteristics and mechanical properties of lotus seedpods with different maturity were carried out, especially focusing on the mechanical properties under shear, tensile and puncture loading method. The damage law of lotus seedpod tissue under different loading conditions were compared and analyzed. The results showed that the moisture content of lotus seeds was the highest in the lotus seed tissue, while the moisture content of the lotus seed epidermis was the lowest. Moreover, as the moisture content decreased, the moisture content of the lotus seed epidermis decreased the most significantly. Comparing the milk ripening period and wax ripening period, the appearance of lotus pods and seeds are fuller during the fully ripe period, with gaps appearing between the seeds and tissues. The shear and tensile properties of the lotus seedpods epidermis were obviously anisotropic, and the external loading mode had a significant impact on the shear and tensile rupture force. With the increase of maturity, the transverse shear rupture force and axial tensile rupture force of the epidermis increased gradually, while the longitudinal shear rupture force and transverse tensile rupture force of the epidermis had no obvious change. The loading speed had no significant effect on the shear and tensile rupture force of the epidermis. The average tensile rupture force of fiber tissues was larger at ripening stage, and there was no significant difference between milk ripening stage and wax ripening stage, and the loading speed had no significant effect on the tensile rupture force. Epidermal puncture damage of lotus seedpod was not affected by epidermal anisotropy. With the increase of maturity, the puncture rupture force of lotus seedpod decreased gradually, while the rupture force of epidermal puncture increased gradually. With the increase of the diameter of the probe, the rupture force of surface puncture and epidermal puncture increased. The loading method had the greatest influence on the loading rupture force of the epidermis, followed by maturity, and the least was loading speed. Different maturity of lotus seed epidermis could achieve less damage under external load under longitudinal shear or transverse stretching, but its anisotropic characteristics make it not universal when designing the machine. After comprehensive analysis of the three loading method, the universal mode of breaking the lotus seedpod was determined, that was, the puncture loading was applied first to destroy the lotus seed, the damage was achieved with less destructive power, and then the tensile cracking force was applied to achieve the efficient tearing of the lotus seed. The above research will provide theoretical basis for the design of fresh lotus seed peeling and threshing machine.
Abstract:
The complex environment of pig farms and the dynamic growth of pigs, leading to changes in body shape, pose challenges for accurate pig segmentation. Video object segmentation, with its ability to utilize temporal information from video sequences, offers a promising solution for handling dynamic objects. In this study, we focus on pigs during dynamic feeding and growth processes in performance testing, constructing a pig video dataset comprising 234 video sequences. We propose a semi-supervised pig video segmentation method based on XMem-SimAM. By introducing SimAM attention for multi-scale feature fusion, the model"s ability to extract temporal information at different scales is enhanced, capturing the temporal characteristics of pigs" dynamic movements. The spatial-channel attention module is employed to strengthen the model"s extraction of temporal semantic feature weights. By optimizing the multi-scale feature fusion strategy and the upsampling module, the temporal correlation information in video sequences is fully utilized, improving the segmentation accuracy of pigs in videos at a fine-grained level. Comparative tests show that the XMem-SimAM model achieves a Jaccard index of 96.9, contour accuracy F-score of 95.8, average metric J F of 98.0, and Dice coefficient of 98.0 on the pig video dataset, outperforming video object segmentation methods such as MiVOS, STCN, DEVA, and XMem++. In the inference phase, the processing speed reaches 58.5FPS, with a memory consumption of 795MB, achieving a good balance between processing efficiency and resource utilization. The results indicate that this study provides a new method for segmenting dynamically growing pigs in complex farm environments.
The complex environment of pig farms and the dynamic growth of pigs, leading to changes in body shape, pose challenges for accurate pig segmentation. Video object segmentation, with its ability to utilize temporal information from video sequences, offers a promising solution for handling dynamic objects. In this study, we focus on pigs during dynamic feeding and growth processes in performance testing, constructing a pig video dataset comprising 234 video sequences. We propose a semi-supervised pig video segmentation method based on XMem-SimAM. By introducing SimAM attention for multi-scale feature fusion, the model"s ability to extract temporal information at different scales is enhanced, capturing the temporal characteristics of pigs" dynamic movements. The spatial-channel attention module is employed to strengthen the model"s extraction of temporal semantic feature weights. By optimizing the multi-scale feature fusion strategy and the upsampling module, the temporal correlation information in video sequences is fully utilized, improving the segmentation accuracy of pigs in videos at a fine-grained level. Comparative tests show that the XMem-SimAM model achieves a Jaccard index of 96.9, contour accuracy F-score of 95.8, average metric J F of 98.0, and Dice coefficient of 98.0 on the pig video dataset, outperforming video object segmentation methods such as MiVOS, STCN, DEVA, and XMem++. In the inference phase, the processing speed reaches 58.5FPS, with a memory consumption of 795MB, achieving a good balance between processing efficiency and resource utilization. The results indicate that this study provides a new method for segmenting dynamically growing pigs in complex farm environments.
Abstract:
In order to optimize the thermal environment of a closed cage-rearing layer house under vertical ventilation mode in autumn, this paper simulated the temperature field, relative humidity field, and air velocity field distribution of the current layer house through computational fluid dynamics (CFD). The accuracy of the numerical model was verified. Through 17 sets of orthogonal simulation experiments, the average THVI (temperature-humidity-velocity index) and coefficient of variation (CVTHVI) of the cage-rearing areas were calculated for ventilation equipment parameters (the angle of the guide plate at the front mountain wall tunnel inlet，the angle of the guide plate at the side wall tunnel inlet，ventilation volume of a suction fan at the end) at three different levels. The results showed that the average relative errors of temperature, relative humidity, and air flow velocity at 24 measuring points on the aisle were respectively 0.38%, 0.52%, and 4.62%, indicating high accuracy of the numerical model; When the ventilation equipment parameters are set to 10°,90° and 42 000 m3/h, the average THVI and coefficient of variation CVTHVI of the airflow field in the the cage-rearing areas are respectively 25.65 and 1.64%, which are 1.61% and 23.93% lower than the original ventilation scheme. This is beneficial for improving the thermal environment suitability and balance of the cage-rearing areas of the layer house.
In order to optimize the thermal environment of a closed cage-rearing layer house under vertical ventilation mode in autumn, this paper simulated the temperature field, relative humidity field, and air velocity field distribution of the current layer house through computational fluid dynamics (CFD). The accuracy of the numerical model was verified. Through 17 sets of orthogonal simulation experiments, the average THVI (temperature-humidity-velocity index) and coefficient of variation (CVTHVI) of the cage-rearing areas were calculated for ventilation equipment parameters (the angle of the guide plate at the front mountain wall tunnel inlet，the angle of the guide plate at the side wall tunnel inlet，ventilation volume of a suction fan at the end) at three different levels. The results showed that the average relative errors of temperature, relative humidity, and air flow velocity at 24 measuring points on the aisle were respectively 0.38%, 0.52%, and 4.62%, indicating high accuracy of the numerical model; When the ventilation equipment parameters are set to 10°,90° and 42 000 m3/h, the average THVI and coefficient of variation CVTHVI of the airflow field in the the cage-rearing areas are respectively 25.65 and 1.64%, which are 1.61% and 23.93% lower than the original ventilation scheme. This is beneficial for improving the thermal environment suitability and balance of the cage-rearing areas of the layer house.
Abstract:
Clarifying the types of viruses in different edible mushrooms during production is the foundation for preventing and controlling fungal virus disease in edible mushrooms. High throughput sequencing technology was used to detect fungal viruses in 53 strains of Pleurotus spp., 10 strains of Ganoderma spp., 17 strains of Flammulina filiformis, and 12 strains of Coprinus comatus. PCR amplification and sequence analysis were performed on newly discovered potential new viruses, and phylogenetic tree analyses were conducted based on sequence comparison. BLASTx sequence alignment results showed that a total of 51 contigs were annotated as 41 viruses detected from 92 strains of four types of edible mushrooms. A total of 13 possible novel viruses were identified through RT-PCR amplification and sequence analysis, including 7 species found in Pleurotus spp., 3 species in Coprinus comatus, 1 species in Flammulina filiformis, and 2 species in Ganoderma spp.. These viruses belong to the +ssRNA viruses, -ssRNA viruses, and dsRNA viruses, and are distributed in 8 viral families, including Barnaviridae, Botuoviridae, Deltaflexiviridae, Mymonaviridae, Partiviridae, Phenuiviridae、Phlegiviridae, and an unclassified member of the order Bunyavirales. In conclusion, there are relatively abundant fungal viruses in the four types of edible mushrooms, among which fungal virus was first discovered in Coprinus comatus and Ganoderma spp.. The discovery of these novel viruses provides a certain reference for further research, prevention, and control of edible mushroom viral diseases.
Clarifying the types of viruses in different edible mushrooms during production is the foundation for preventing and controlling fungal virus disease in edible mushrooms. High throughput sequencing technology was used to detect fungal viruses in 53 strains of Pleurotus spp., 10 strains of Ganoderma spp., 17 strains of Flammulina filiformis, and 12 strains of Coprinus comatus. PCR amplification and sequence analysis were performed on newly discovered potential new viruses, and phylogenetic tree analyses were conducted based on sequence comparison. BLASTx sequence alignment results showed that a total of 51 contigs were annotated as 41 viruses detected from 92 strains of four types of edible mushrooms. A total of 13 possible novel viruses were identified through RT-PCR amplification and sequence analysis, including 7 species found in Pleurotus spp., 3 species in Coprinus comatus, 1 species in Flammulina filiformis, and 2 species in Ganoderma spp.. These viruses belong to the +ssRNA viruses, -ssRNA viruses, and dsRNA viruses, and are distributed in 8 viral families, including Barnaviridae, Botuoviridae, Deltaflexiviridae, Mymonaviridae, Partiviridae, Phenuiviridae、Phlegiviridae, and an unclassified member of the order Bunyavirales. In conclusion, there are relatively abundant fungal viruses in the four types of edible mushrooms, among which fungal virus was first discovered in Coprinus comatus and Ganoderma spp.. The discovery of these novel viruses provides a certain reference for further research, prevention, and control of edible mushroom viral diseases.
Abstract:
The efficient and stable genetic transformation system of plants is an important technical support for gene function analysis and molecular breeding. The lack of a complete tissue culture system has seriously hindered its application in many plants, especially crops. In recent years, many efficient non-tissue culture genetic transformation systems have been established to solve the above problems. This review focuses on the application of Agrobacterium-mediated non-tissue culture genetic transformation systems, including flower organ infection, cut-dip-bud (CDB) delivery, regenerative activity–dependent in planta injection delivery (RAPID), seed infection, developmental regulatory (DR) gene assisted transformation and virus delivery in plants, the influencing factors of transformation efficiency and gene editing applications. The application of pollen tube channel method, particle bombardment method and nano delivery method in plants independent of Agrobacterium is summarized. This review will provide reference for more species to establish efficient, simple and genotype-independent non-tissue culture genetic transformation system, and help plant functional gene research and molecular breeding practice.
The efficient and stable genetic transformation system of plants is an important technical support for gene function analysis and molecular breeding. The lack of a complete tissue culture system has seriously hindered its application in many plants, especially crops. In recent years, many efficient non-tissue culture genetic transformation systems have been established to solve the above problems. This review focuses on the application of Agrobacterium-mediated non-tissue culture genetic transformation systems, including flower organ infection, cut-dip-bud (CDB) delivery, regenerative activity–dependent in planta injection delivery (RAPID), seed infection, developmental regulatory (DR) gene assisted transformation and virus delivery in plants, the influencing factors of transformation efficiency and gene editing applications. The application of pollen tube channel method, particle bombardment method and nano delivery method in plants independent of Agrobacterium is summarized. This review will provide reference for more species to establish efficient, simple and genotype-independent non-tissue culture genetic transformation system, and help plant functional gene research and molecular breeding practice.
Abstract:
To achieve online automatic measurement of the mass flow rate of granular materials in the chute, according to the difference in dielectric properties between granular materials and air, a chute mass flow meter for granular materials based on the capacitance method is designed. The device uses STM32 microcontroller, the capacitance-to-digital Converter chip AD7746 and the plate conversion circuit with MT8816 as core chip of the to build a data acquisition system to achieves effective acquisition of the of eight-plate rotary excitation sensors. A mass flow test bench was built, maize, wheat and pellet compound feed as test materials，the relationship between mass flow rate and capacitance output variation was calibrated, and the mass flow prediction models of three kinds of granular materials were constructed. The model coefficient of determination R2 is 0.990 4, 0.993 9 and 0.987 9 respectively. The chute mass flow meter for granular materials performs well when the chute inclination angles of 15°, 25°, 35°, 45°,55°，the maize and wheat mass is 30, 50 and 70 kg，the pellet compound feed mass is 30，50，65 kg . Regarding measurement accuracy, the average relative errors of maize, wheat and pellet compound feed were measured 3.11%, 3.76% and 3.55% respectively. The results show that it is feasible to apply the capacitance method to the online measurement of mass flow rate during the transport of detect the mass flow of granular materials in the chute, and can achieve the online automatic measurement of mass flow rate of measuring granular materials.
To achieve online automatic measurement of the mass flow rate of granular materials in the chute, according to the difference in dielectric properties between granular materials and air, a chute mass flow meter for granular materials based on the capacitance method is designed. The device uses STM32 microcontroller, the capacitance-to-digital Converter chip AD7746 and the plate conversion circuit with MT8816 as core chip of the to build a data acquisition system to achieves effective acquisition of the of eight-plate rotary excitation sensors. A mass flow test bench was built, maize, wheat and pellet compound feed as test materials，the relationship between mass flow rate and capacitance output variation was calibrated, and the mass flow prediction models of three kinds of granular materials were constructed. The model coefficient of determination R2 is 0.990 4, 0.993 9 and 0.987 9 respectively. The chute mass flow meter for granular materials performs well when the chute inclination angles of 15°, 25°, 35°, 45°,55°，the maize and wheat mass is 30, 50 and 70 kg，the pellet compound feed mass is 30，50，65 kg . Regarding measurement accuracy, the average relative errors of maize, wheat and pellet compound feed were measured 3.11%, 3.76% and 3.55% respectively. The results show that it is feasible to apply the capacitance method to the online measurement of mass flow rate during the transport of detect the mass flow of granular materials in the chute, and can achieve the online automatic measurement of mass flow rate of measuring granular materials.
Abstract:
A pathogenic bacterial strain of B20200824 was isolated from the brain, spine, liver and kidney of diseased Pelophllax nigromaculatus. The strain was identified by physiological and biochemical assays, 16S rRNA sequencing and evolutionary tree construction, then the susceptibility and the minimal inhibitory concentrations of antibiotics were determined by disk diffusion and broth micro-dilution methods, respectively. After identification, the strain was found to be a Gram-negative short bacillus with biochemical characteristics consistent with those of proteus vulgaris. Moreover, 16S rRNA sequencing and phylogenetic results revealed that the strain had a close genetic relationship with proteus vulgaris, which shared over 99% genetic homology. Thus, B20200824 was identified as proteus vulgaris. The results of drug susceptibility test showed that the strain was resistant to norfloxacin, amoxicillin, enrofloxacin and other 3 drugs, intermediate to doxycycline and erythromycin, and susceptible to azithromycin, cefotaxime, florfenicol ant 2 other drugs. Similar results were obtained according to the results of the minimum inhibitory concentration assay.
A pathogenic bacterial strain of B20200824 was isolated from the brain, spine, liver and kidney of diseased Pelophllax nigromaculatus. The strain was identified by physiological and biochemical assays, 16S rRNA sequencing and evolutionary tree construction, then the susceptibility and the minimal inhibitory concentrations of antibiotics were determined by disk diffusion and broth micro-dilution methods, respectively. After identification, the strain was found to be a Gram-negative short bacillus with biochemical characteristics consistent with those of proteus vulgaris. Moreover, 16S rRNA sequencing and phylogenetic results revealed that the strain had a close genetic relationship with proteus vulgaris, which shared over 99% genetic homology. Thus, B20200824 was identified as proteus vulgaris. The results of drug susceptibility test showed that the strain was resistant to norfloxacin, amoxicillin, enrofloxacin and other 3 drugs, intermediate to doxycycline and erythromycin, and susceptible to azithromycin, cefotaxime, florfenicol ant 2 other drugs. Similar results were obtained according to the results of the minimum inhibitory concentration assay.
SUN Jing-Guo, CHANG Yi-Fei, ZHENG Xiao-Mei, QIAO Bao-Ming, FAN You-Lun, TIAN Hui-Wen, CHEN Tao, CAI Li-Guang, ZHAI Lin-Dun, SUN Xue-Cheng
Abstract:
Using cigar-filler variety Chuxue 14 (CX-14) as a material, a field experiment was conducted to study the effects of different sulfur fertilizer dosages (0, 60, 120 and 180 kg S/hm2) on the agronomic properties, yield, quality and combustibility of cigar tobacco, in order to provide a basis for determining the appropriate sulfur fertilizer dosage and fertilization management for cigar tobacco. The results showed that applying sulfur fertilizer increased the height, maximum leaf width, leaf length, effective leaf number, and SPAD value of cigar tobacco during the field-growth period, increased yield and superior tobacco rate, thus increased output value of cigar tobacco. The yield and output value were highest under 120 kg/hm2 sulfur application, and the superior tobacco rate was highest under 60 kg/hm2 sulfur application. Applying sulfur fertilizer could increase the total sugar, reducing sugar, reducing sugar proportion, and crude protein contents of cigar tobacco, thus could improve the intrinsic quality of cigar tobacco. 60 kg/hm2 sulfur application improved the combustion performance of cigar tobacco by increasing the activation energy during the combustion process, reducing the initial temperature, maximum heat flux temperature and frequency factor, reducing ash content, increasing maximum heat flux and total heat release. Compared with no sulfur application, the maximum heat flux and total heat release were increased by 10.9% and 6.3%, while the frequency factor during combustion decreased by 43.7% under 60 kg/hm2 sulfur application. The above results indicate that 60 kg/hm2 is the appropriate sulfur application for cigar tobacco under the conditions of this experiment. Although excessive sulfur fertilizer application (120 and 180 kg/hm2) can increase the yield and economic benefits of cigar tobacco, it is not conducive to the improvement of tobacco combustion performance. Therefore, in the process of cigar tobacco planting, it can be considered to appropriately reduce the application of potassium sulfate fertilizer, and replace it with potassium carbonate and other potash fertilizers, in order to reduce the negative impacts of excessive sulfur fertilizer on the combustion performance of tobacco as well as soil acidification.
Using cigar-filler variety Chuxue 14 (CX-14) as a material, a field experiment was conducted to study the effects of different sulfur fertilizer dosages (0, 60, 120 and 180 kg S/hm2) on the agronomic properties, yield, quality and combustibility of cigar tobacco, in order to provide a basis for determining the appropriate sulfur fertilizer dosage and fertilization management for cigar tobacco. The results showed that applying sulfur fertilizer increased the height, maximum leaf width, leaf length, effective leaf number, and SPAD value of cigar tobacco during the field-growth period, increased yield and superior tobacco rate, thus increased output value of cigar tobacco. The yield and output value were highest under 120 kg/hm2 sulfur application, and the superior tobacco rate was highest under 60 kg/hm2 sulfur application. Applying sulfur fertilizer could increase the total sugar, reducing sugar, reducing sugar proportion, and crude protein contents of cigar tobacco, thus could improve the intrinsic quality of cigar tobacco. 60 kg/hm2 sulfur application improved the combustion performance of cigar tobacco by increasing the activation energy during the combustion process, reducing the initial temperature, maximum heat flux temperature and frequency factor, reducing ash content, increasing maximum heat flux and total heat release. Compared with no sulfur application, the maximum heat flux and total heat release were increased by 10.9% and 6.3%, while the frequency factor during combustion decreased by 43.7% under 60 kg/hm2 sulfur application. The above results indicate that 60 kg/hm2 is the appropriate sulfur application for cigar tobacco under the conditions of this experiment. Although excessive sulfur fertilizer application (120 and 180 kg/hm2) can increase the yield and economic benefits of cigar tobacco, it is not conducive to the improvement of tobacco combustion performance. Therefore, in the process of cigar tobacco planting, it can be considered to appropriately reduce the application of potassium sulfate fertilizer, and replace it with potassium carbonate and other potash fertilizers, in order to reduce the negative impacts of excessive sulfur fertilizer on the combustion performance of tobacco as well as soil acidification.
Abstract:
In order to clarify the resistance of the current rice maincrop varieties to Bipolaris oryzae and the potential physiological and biochemical resistance mechanisms, this study evaluated the resistance levels of 20 main rice germplasm of Sichuan and 5 control rice varieties to B. oryzae using a potting resistance identification method, determined the activities of five defensive enzymes in the leaves of different resistance levels, and analyzed the leaf blades of the rice seedlings from the resistant and susceptible varieties by gas chromatography/mass spectrometry (GC/MS). The results showed that 'Yu Xiangnuo No.1' and 'Zhe Japonica Excellent No.4' were highly resistant varieties, while five varieties, including 'Zhe Japonica Excellent No.1578', behaved as moderately resistant varieties, and the rest of the varieties were disease susceptible The remaining varieties were susceptible varieties; the enzyme activities of five enzymes such as SOD, PPO, PAL, POD and CAT in disease-resistant rice varieties and susceptible rice varieties were first increased and then decreased, and the enzyme activities of the disease-resistant varieties were significantly higher than those of the susceptible varieties; a total of 18 secondary metabolites were obtained, and the contents of four secondary metabolites, including ribitol, D-glucose, malic acid, and 2,3,4-trihydroxybutyric acid, differed significantly between disease-resistant and disease-susceptible varieties, and between inoculated B. oryzae or not on the same variety. Therefore, the disease-resistant varieties of rice can resist the infestation of B. oryzae by enhancing the activities of five defensive enzymes and the contents of four secondary metabolites.
In order to clarify the resistance of the current rice maincrop varieties to Bipolaris oryzae and the potential physiological and biochemical resistance mechanisms, this study evaluated the resistance levels of 20 main rice germplasm of Sichuan and 5 control rice varieties to B. oryzae using a potting resistance identification method, determined the activities of five defensive enzymes in the leaves of different resistance levels, and analyzed the leaf blades of the rice seedlings from the resistant and susceptible varieties by gas chromatography/mass spectrometry (GC/MS). The results showed that 'Yu Xiangnuo No.1' and 'Zhe Japonica Excellent No.4' were highly resistant varieties, while five varieties, including 'Zhe Japonica Excellent No.1578', behaved as moderately resistant varieties, and the rest of the varieties were disease susceptible The remaining varieties were susceptible varieties; the enzyme activities of five enzymes such as SOD, PPO, PAL, POD and CAT in disease-resistant rice varieties and susceptible rice varieties were first increased and then decreased, and the enzyme activities of the disease-resistant varieties were significantly higher than those of the susceptible varieties; a total of 18 secondary metabolites were obtained, and the contents of four secondary metabolites, including ribitol, D-glucose, malic acid, and 2,3,4-trihydroxybutyric acid, differed significantly between disease-resistant and disease-susceptible varieties, and between inoculated B. oryzae or not on the same variety. Therefore, the disease-resistant varieties of rice can resist the infestation of B. oryzae by enhancing the activities of five defensive enzymes and the contents of four secondary metabolites.
Abstract:
Citrus is the world's largest fruit and an important cash crop in the world. The post-harvest losses of citrus are severe, causing serious economic losses to the citrus industry. In order to reduce the decay of citrus and improve the value of the commodity, Prochloraz and Imazalil are often used in the postharvest handling. In this study, a detection technique of Prochloraz and Imazalil was established based on HPLC. Using this technique, the dynamic of Prochloraz and Imazalil on the postharvest sorting line was detected. It was found that Prochloraz was stable at room temperature, while Imazalil was prone to degrade, and the concentrations of Prochloraz and Imazalil were reduced by 98.6 μg/mL and 290.3 μg/mL, respectively, after 6 h of working on 15 t of Satsuma orange. The results obtained will guide the use of fungicides in the postharvest handling of citrus.
Citrus is the world's largest fruit and an important cash crop in the world. The post-harvest losses of citrus are severe, causing serious economic losses to the citrus industry. In order to reduce the decay of citrus and improve the value of the commodity, Prochloraz and Imazalil are often used in the postharvest handling. In this study, a detection technique of Prochloraz and Imazalil was established based on HPLC. Using this technique, the dynamic of Prochloraz and Imazalil on the postharvest sorting line was detected. It was found that Prochloraz was stable at room temperature, while Imazalil was prone to degrade, and the concentrations of Prochloraz and Imazalil were reduced by 98.6 μg/mL and 290.3 μg/mL, respectively, after 6 h of working on 15 t of Satsuma orange. The results obtained will guide the use of fungicides in the postharvest handling of citrus.
Abstract:
Pinellia ternata diseases constitute a significant impediment to the industrial development of Pinellia ternata. This research aims to screen and identify excellent strains of beneficial microorganisms resistant to Pinellia ternata, with the ultimate goal of formulating them into microbial fertilizers and exploring their effects on promoting plant growth and disease resistance. Nine strains exhibiting antagonistic effects against various pathogens of Pinellia ternata, including Fusarium oxysporum, Aspergillus, Fusarium, Phytophthora capsici and Fusarium solani, were isolated and screened from the rhizospheric soil of Pinellia ternata. Through the screening and identification of functional bacterial strains, along with the analysis of their determination of their antibacterial capabilities and the evaluation of the growth-promoting and disease control effects of their biological organic fertilizer on Pinellia ternata, the results indicate that strain 21-2 exhibited the most effective antibacterial activity. Upon identification, it was confirmed to be Paenibacillus polymyxa. Strain 21-2 demonstrates notable inhibitory effects against five common pathogens of Pinellia ternata and significantly promotes the germination of Pinellia ternata seeds. The suspension of strain 21-2 exhibits a disease control efficacy of 43.83% against Pinellia ternata diseases, leading to significant improvements in plant height, fresh weight, tuberous bulb, and chlorophyll content, among other growth indicators. The bio-organic fertilizer, comprised of Paenibacillus polymyxa 21-2, straw-derived biochar, and organic fertilizer from chicken manure, exhibits a disease control efficacy of 61.90% against Pinellia ternata diseases, showcasing promising prospects and developmental potential for practical applications.
Pinellia ternata diseases constitute a significant impediment to the industrial development of Pinellia ternata. This research aims to screen and identify excellent strains of beneficial microorganisms resistant to Pinellia ternata, with the ultimate goal of formulating them into microbial fertilizers and exploring their effects on promoting plant growth and disease resistance. Nine strains exhibiting antagonistic effects against various pathogens of Pinellia ternata, including Fusarium oxysporum, Aspergillus, Fusarium, Phytophthora capsici and Fusarium solani, were isolated and screened from the rhizospheric soil of Pinellia ternata. Through the screening and identification of functional bacterial strains, along with the analysis of their determination of their antibacterial capabilities and the evaluation of the growth-promoting and disease control effects of their biological organic fertilizer on Pinellia ternata, the results indicate that strain 21-2 exhibited the most effective antibacterial activity. Upon identification, it was confirmed to be Paenibacillus polymyxa. Strain 21-2 demonstrates notable inhibitory effects against five common pathogens of Pinellia ternata and significantly promotes the germination of Pinellia ternata seeds. The suspension of strain 21-2 exhibits a disease control efficacy of 43.83% against Pinellia ternata diseases, leading to significant improvements in plant height, fresh weight, tuberous bulb, and chlorophyll content, among other growth indicators. The bio-organic fertilizer, comprised of Paenibacillus polymyxa 21-2, straw-derived biochar, and organic fertilizer from chicken manure, exhibits a disease control efficacy of 61.90% against Pinellia ternata diseases, showcasing promising prospects and developmental potential for practical applications.
Abstract:
In response to the challenge of accurately predicting plant-plant inhibitory and promotive interactions based on prior knowledge, this study constructs a heterogeneous network derived from plant interactions and proposes a graph neural network-driven method to tackle this issue. The method is primarily composed of three modules: a representation learner, an interaction identifier, and a type classifier. The representation learner is responsible for extracting representations of interactions. The interaction identifier collaborates with the representation learner to predict whether an interaction exists on target plant types and applies perturbations to the type classifier to maximally acquire transferable features across different interaction types. The type classifier is designed to accurately distinguish between types of plant interactions to avoid being influenced by the interaction identifier. Finally, the inter adversarial relationship among the three modules is leveraged to enhance robustness against the differences in the types of inhibitory and promotive interactions, thereby effectively addressing the prediction challenge of plant-plant interactions. This method demonstrated improvements in AUC, Precision, and Accuracy by 7.74%, 1.61%, and 8.62%, respectively, compared to existing methods, achieving scores of 92.00%, 80.12%, and 86.21% on a companion plant dataset. The results indicate that the method accurately predicts interactions between plants by effectively reducing the interference from target types.
In response to the challenge of accurately predicting plant-plant inhibitory and promotive interactions based on prior knowledge, this study constructs a heterogeneous network derived from plant interactions and proposes a graph neural network-driven method to tackle this issue. The method is primarily composed of three modules: a representation learner, an interaction identifier, and a type classifier. The representation learner is responsible for extracting representations of interactions. The interaction identifier collaborates with the representation learner to predict whether an interaction exists on target plant types and applies perturbations to the type classifier to maximally acquire transferable features across different interaction types. The type classifier is designed to accurately distinguish between types of plant interactions to avoid being influenced by the interaction identifier. Finally, the inter adversarial relationship among the three modules is leveraged to enhance robustness against the differences in the types of inhibitory and promotive interactions, thereby effectively addressing the prediction challenge of plant-plant interactions. This method demonstrated improvements in AUC, Precision, and Accuracy by 7.74%, 1.61%, and 8.62%, respectively, compared to existing methods, achieving scores of 92.00%, 80.12%, and 86.21% on a companion plant dataset. The results indicate that the method accurately predicts interactions between plants by effectively reducing the interference from target types.
Abstract:
In order to construct a prediction model with high prediction accuracy and strong generalization ability for hydrothermal biofuel hydrogen-rich content, and to deeply explore the laws and mechanisms of hydrothermal conversion of biomass, this paper, based on 243 groups of experimental data collected in the literature for hydrothermal preparation of hydrogen-rich biofuel from high-moisture, high-fat wastes such as diseased and dead livestock and poultry, algae, etc., and adopting two types of high-fitness machine learning algorithms, namely, Random Forest and Extreme Gradient Enhancement Tree, establishes a high-precision and wide-area hydrothermal Based on the mathematical prediction model, the contribution of hydrothermal oil formation conditions, the local dependence response behavior and its mutual coupling law were analyzed by using SHAP interpretable technology and local dependence analysis method. The results showed that: the lipid content and hydrogen content in the high-moisture, high-fat waste were the determining factors for the preparation of hydrogen-rich biofuel, and they ranked the top two in terms of their contribution to the enrichment of hydrogen in the oil phase, which could significantly affect the accumulation of hydrogen in the oil phase; with the increase in the hydrogen content of the feedstock, the hydrogen content in the oil phase was enhanced, indicating that hydrogen-rich feedstock provided a convenient condition for the preparation of hydrogen-rich biofuel, with an enhancement effect of up to 4 wt%. And the higher heating value of the feedstock was the main inhibiting factor for the hydrogen-enriched behavior of biofuel, with an inhibiting effect of up to 4 wt%. In addition, from the interactions among the characterization categories, the coupling between elemental information, industrial information and biomass component information is strong, but the local coupling between feedstock properties and operating conditions is small.
In order to construct a prediction model with high prediction accuracy and strong generalization ability for hydrothermal biofuel hydrogen-rich content, and to deeply explore the laws and mechanisms of hydrothermal conversion of biomass, this paper, based on 243 groups of experimental data collected in the literature for hydrothermal preparation of hydrogen-rich biofuel from high-moisture, high-fat wastes such as diseased and dead livestock and poultry, algae, etc., and adopting two types of high-fitness machine learning algorithms, namely, Random Forest and Extreme Gradient Enhancement Tree, establishes a high-precision and wide-area hydrothermal Based on the mathematical prediction model, the contribution of hydrothermal oil formation conditions, the local dependence response behavior and its mutual coupling law were analyzed by using SHAP interpretable technology and local dependence analysis method. The results showed that: the lipid content and hydrogen content in the high-moisture, high-fat waste were the determining factors for the preparation of hydrogen-rich biofuel, and they ranked the top two in terms of their contribution to the enrichment of hydrogen in the oil phase, which could significantly affect the accumulation of hydrogen in the oil phase; with the increase in the hydrogen content of the feedstock, the hydrogen content in the oil phase was enhanced, indicating that hydrogen-rich feedstock provided a convenient condition for the preparation of hydrogen-rich biofuel, with an enhancement effect of up to 4 wt%. And the higher heating value of the feedstock was the main inhibiting factor for the hydrogen-enriched behavior of biofuel, with an inhibiting effect of up to 4 wt%. In addition, from the interactions among the characterization categories, the coupling between elemental information, industrial information and biomass component information is strong, but the local coupling between feedstock properties and operating conditions is small.
Abstract:
Addressing the challenges of localizing true lesion areas in fish disease detection due to irregular lesion shapes, unclear textures, and scattered lesion spots, a CEH-YOLOv8 fish disease detection method based on dual-channel layered collaborative is proposed. Firstly, a dual-channel feature extraction network is introduced to enhance the model's ability to extract irregular lesion areas with unclear textures. Subsequently, an Efficient Channel Spatial Attention (ECSA) mechanism is proposed to improve the model's recognition capability for distributed targets. Additionally, to reinforce the improved backbone network, a Hierarchical and Balanced Feature Pyramid Network (HBFPN) is presented, which integrates features extracted from the backbone network at different levels to enhance the model's feature representation capability. Experimental results demonstrate that the CEH-YOLOv8 network achieves an accuracy rate of 83.2%, a recall rate of 72.5%, and a mean Average Precision (mAP) of 76.2% for fish disease detection. Compared to the state-of-the-art YOLOv10 method, it exhibits improvements of 6.9, 11.6, and 11.9 percentage points, respectively, and enhancements of 4.3, 6.9, and 6 percentage points compared to the original model. The inference time for a single frame is 9.1 ms. These results indicate that the improved YOLOv8 network can accurately screen fish with diseases, enabling early detection of fishery diseases to reduce economic losses.
Addressing the challenges of localizing true lesion areas in fish disease detection due to irregular lesion shapes, unclear textures, and scattered lesion spots, a CEH-YOLOv8 fish disease detection method based on dual-channel layered collaborative is proposed. Firstly, a dual-channel feature extraction network is introduced to enhance the model's ability to extract irregular lesion areas with unclear textures. Subsequently, an Efficient Channel Spatial Attention (ECSA) mechanism is proposed to improve the model's recognition capability for distributed targets. Additionally, to reinforce the improved backbone network, a Hierarchical and Balanced Feature Pyramid Network (HBFPN) is presented, which integrates features extracted from the backbone network at different levels to enhance the model's feature representation capability. Experimental results demonstrate that the CEH-YOLOv8 network achieves an accuracy rate of 83.2%, a recall rate of 72.5%, and a mean Average Precision (mAP) of 76.2% for fish disease detection. Compared to the state-of-the-art YOLOv10 method, it exhibits improvements of 6.9, 11.6, and 11.9 percentage points, respectively, and enhancements of 4.3, 6.9, and 6 percentage points compared to the original model. The inference time for a single frame is 9.1 ms. These results indicate that the improved YOLOv8 network can accurately screen fish with diseases, enabling early detection of fishery diseases to reduce economic losses.
Abstract:
The digitalization of aquaculture industry is the only way for the modernization of China's fishery industry. Based on the main ways of the integration of digital technology and aquaculture, this paper analyzes the typical cases empowered by digital technology in China, analyzes the main modes and bottlenecks of the digital development of China's aquaculture industry, and explores the basic path of the digital development of China's aquaculture industry based on relevant foreign experience, and puts forward relevant suggestions. This paper argues that in order to improve the digital development level of aquaculture industry in China, it is necessary to increase the investment and management of aquaculture data collection and utilization, support the research and development and integrated application of digital technology in aquaculture, improve the participation of farmers in the digitalization process of aquaculture, and strengthen the research and formulation of policies related to the digitalization of aquaculture.
The digitalization of aquaculture industry is the only way for the modernization of China's fishery industry. Based on the main ways of the integration of digital technology and aquaculture, this paper analyzes the typical cases empowered by digital technology in China, analyzes the main modes and bottlenecks of the digital development of China's aquaculture industry, and explores the basic path of the digital development of China's aquaculture industry based on relevant foreign experience, and puts forward relevant suggestions. This paper argues that in order to improve the digital development level of aquaculture industry in China, it is necessary to increase the investment and management of aquaculture data collection and utilization, support the research and development and integrated application of digital technology in aquaculture, improve the participation of farmers in the digitalization process of aquaculture, and strengthen the research and formulation of policies related to the digitalization of aquaculture.
Abstract:
Paenibacillus polymyxa NBmelon-1 is a highly effective biocontrol bacterial strain isolated from melon roots. To study the genetic information of P. polymyxa NBmelon-1 and investigate its biocontrol mechanisms, the whole genome of strain NBmelon-1 was sequenced using the third-generation PacBio sequencing technique, and the genome was used to mine potential functional genes for biosynthesis of the secondary metabolites. Validation was carried out by detecting expression of the genes related to antifungal activity and plant-growth promotion and testing the antifungal activity of the crude extracts. The results showed that the genome size of P. polymyxa NBmelon-1 was 5.7 Mb with the GC content of 45.68%, harboring 4,984 coding genes. The genome contained genes related to induction of plant resistance and promotion of plant growth as well as the genes for hydrolases. A total of five gene clusters for biosynthesis of lipopeptide metabolites were predicted, including those for polymyxin, fusaricidin B, tridecaptin M, tridecaptin and peanilipoheptin. Crude extract was obtained from the cultures of NBmelon-1 using the acid precipitation method, and it showed a significant inhibitory effect on growth of a variety of pathogenic fungi from melon. The growth-promoting potential test showed that the bacterial strain was able to synthesize the phytohormone IAA, to produce iron carriers, and to provide nitrogen to plants. In conclusion,?P. polymyxa?NBmelon-1 has good prospects for agricultural applications.
Paenibacillus polymyxa NBmelon-1 is a highly effective biocontrol bacterial strain isolated from melon roots. To study the genetic information of P. polymyxa NBmelon-1 and investigate its biocontrol mechanisms, the whole genome of strain NBmelon-1 was sequenced using the third-generation PacBio sequencing technique, and the genome was used to mine potential functional genes for biosynthesis of the secondary metabolites. Validation was carried out by detecting expression of the genes related to antifungal activity and plant-growth promotion and testing the antifungal activity of the crude extracts. The results showed that the genome size of P. polymyxa NBmelon-1 was 5.7 Mb with the GC content of 45.68%, harboring 4,984 coding genes. The genome contained genes related to induction of plant resistance and promotion of plant growth as well as the genes for hydrolases. A total of five gene clusters for biosynthesis of lipopeptide metabolites were predicted, including those for polymyxin, fusaricidin B, tridecaptin M, tridecaptin and peanilipoheptin. Crude extract was obtained from the cultures of NBmelon-1 using the acid precipitation method, and it showed a significant inhibitory effect on growth of a variety of pathogenic fungi from melon. The growth-promoting potential test showed that the bacterial strain was able to synthesize the phytohormone IAA, to produce iron carriers, and to provide nitrogen to plants. In conclusion,?P. polymyxa?NBmelon-1 has good prospects for agricultural applications.
Abstract:
Abstract:'Zaohong' navel orange[Citrus sinensis (L.)Osbeck + C. unshiu Marc.] is a graft chimaera from'Robertson' navel orange[C. sinensis (L.)Osbeck] and 'Guoqing 1'satsuma mandarin [C. unshiu Marc.]. The 'Zaohong' navel orange has the peel of a navel orange and the flesh of a tangerine. It has a good flavor that has made it a favorite in recent years. The aim of this study was to evaluate the effects of different rootstocks on tree growth and fruit quality of 'Zaohong' navel orange, and provide a scientific basis for the selection of optimal rootstock combinations for the growers of 'Zaohong' navel orange species.This experiment utilized 'Zaohong' navel orange as the material and compared the effects of three different rootstock combinations on the growth of the oranges and the quality of the fruit. The rootstock combinations included （C. reticulata Blanco cv. Red tangerine）(Rt),（Poncirus trifoliata Raf.）(Pt) , and (Pt+Rt)(originally Poncirus trifoliata then Red tangerine was used to inarch Poncirus trifoliata).The results showed that there were differences in Photosynthesis and its products, tree growth, fruit yield and quality of 'Zaohong' navel orange grafted on different rootstocks. In terms of soluble sugar content in leaves, intercellular CO2 concentration and stomatal conductivity, Pt > Pt+Rt > Rt; in terms of tree growth and fruit yield:plant height, crown?diameter, shoot length, leaf size and fruit yield showed Rt> Pt+Rt> Rt; In terms of fruit quality, Pt rootstocks were higher than the other combinations in fruit soluble solids content and total acid content, and there was no significant difference in the solids-acid ratio of the different rootstocks. In terms of fruit weight, Rt rootstocks and Pt+Rt rootstocks were larger than Pt, and Pt rootstocks had unstable fruit sizes among different years.On the whole, Red tangerine rootstock has stronger tree strength, higher fruit yield and single fruit weight,so it has better economic benefits and is suitable for promotion and use in the Three Gorges Reservoir area.
Abstract:'Zaohong' navel orange[Citrus sinensis (L.)Osbeck + C. unshiu Marc.] is a graft chimaera from'Robertson' navel orange[C. sinensis (L.)Osbeck] and 'Guoqing 1'satsuma mandarin [C. unshiu Marc.]. The 'Zaohong' navel orange has the peel of a navel orange and the flesh of a tangerine. It has a good flavor that has made it a favorite in recent years. The aim of this study was to evaluate the effects of different rootstocks on tree growth and fruit quality of 'Zaohong' navel orange, and provide a scientific basis for the selection of optimal rootstock combinations for the growers of 'Zaohong' navel orange species.This experiment utilized 'Zaohong' navel orange as the material and compared the effects of three different rootstock combinations on the growth of the oranges and the quality of the fruit. The rootstock combinations included （C. reticulata Blanco cv. Red tangerine）(Rt),（Poncirus trifoliata Raf.）(Pt) , and (Pt+Rt)(originally Poncirus trifoliata then Red tangerine was used to inarch Poncirus trifoliata).The results showed that there were differences in Photosynthesis and its products, tree growth, fruit yield and quality of 'Zaohong' navel orange grafted on different rootstocks. In terms of soluble sugar content in leaves, intercellular CO2 concentration and stomatal conductivity, Pt > Pt+Rt > Rt; in terms of tree growth and fruit yield:plant height, crown?diameter, shoot length, leaf size and fruit yield showed Rt> Pt+Rt> Rt; In terms of fruit quality, Pt rootstocks were higher than the other combinations in fruit soluble solids content and total acid content, and there was no significant difference in the solids-acid ratio of the different rootstocks. In terms of fruit weight, Rt rootstocks and Pt+Rt rootstocks were larger than Pt, and Pt rootstocks had unstable fruit sizes among different years.On the whole, Red tangerine rootstock has stronger tree strength, higher fruit yield and single fruit weight,so it has better economic benefits and is suitable for promotion and use in the Three Gorges Reservoir area.
Abstract:
To enhance the accuracy and efficiency of fish surface pathology recognition, and to address the current issues of heavy reliance on manual processes and low recognition accuracy, this study constructed a fish surface pathology dataset for four types of diseases that are both prevalent and harmful to fish. Based on this, an improved and optimized Resnet-18 model was developed by integrating both spatial attention and SE channel attention mechanisms to create a high-accuracy DBA_Resnet-18 model. A real-time intelligent fish disease recognition and visualization system was also developed using this model. The improved model incorporates the SE channel attention module in the middle of the network and introduces spatial attention at the end of the network.Test results show that the DBA_Resnet-18 model achieved a classification accuracy of 96.75% for fish surface pathologies, which is respectively 1.71, 2.12, 2.37, 2.83, 2.51, 2.23, 2.50, and 3.53 percentage points higher than the commonly used models Resnet-18, Resnet-34, Resnet-50, Resnet-101, Swin Transformer, VGG-16, VGG-19, and AlexNet. The results indicate that the proposed model and the intelligent fish disease recognition visualization system can rapidly and accurately classify different types of fish surface pathologies, achieving an intelligent fish disease recognition system that can be applied in practical environments for diagnosing fish surface pathology types.
To enhance the accuracy and efficiency of fish surface pathology recognition, and to address the current issues of heavy reliance on manual processes and low recognition accuracy, this study constructed a fish surface pathology dataset for four types of diseases that are both prevalent and harmful to fish. Based on this, an improved and optimized Resnet-18 model was developed by integrating both spatial attention and SE channel attention mechanisms to create a high-accuracy DBA_Resnet-18 model. A real-time intelligent fish disease recognition and visualization system was also developed using this model. The improved model incorporates the SE channel attention module in the middle of the network and introduces spatial attention at the end of the network.Test results show that the DBA_Resnet-18 model achieved a classification accuracy of 96.75% for fish surface pathologies, which is respectively 1.71, 2.12, 2.37, 2.83, 2.51, 2.23, 2.50, and 3.53 percentage points higher than the commonly used models Resnet-18, Resnet-34, Resnet-50, Resnet-101, Swin Transformer, VGG-16, VGG-19, and AlexNet. The results indicate that the proposed model and the intelligent fish disease recognition visualization system can rapidly and accurately classify different types of fish surface pathologies, achieving an intelligent fish disease recognition system that can be applied in practical environments for diagnosing fish surface pathology types.
Abstract:
To identify key genes involved in maize salt stress tolerance, the ZmDIR11 gene, a member of the DIR gene family, was cloned from maize and its gene and protein structures were predicted. Its expression pattern was analyzed, and its role in salt stress tolerance was further explored in the B73-EMS mutant. The results showed that ZmDIR11 encodes a peptide containing the Dirigent domain, and its promoter region contains ARE, MYB, MYC, STRE, LTR, and MBS structural elements, which are related to non-biological stress regulation. ZmDIR11 is predominantly expressed in the maize root system and is induced to express under salt stress. It is subcellularly localized to the endoplasmic reticulum. After salt stress treatment, the growth vigor and material accumulation of the mutant maize plants were significantly lower than those of the wild-type B73 material, and the oxidative metabolism regulation pathway, proline accumulation, chlorophyll synthesis, lignin accumulation, and Na+/K+ transport pathway were inhibited, with significantly lower related metabolic indicators than those of the wild-type B73 material. The results show that ZmDIR11 positively regulates the maize salt stress metabolic pathway and is mutated to reduce maize salt tolerance.
To identify key genes involved in maize salt stress tolerance, the ZmDIR11 gene, a member of the DIR gene family, was cloned from maize and its gene and protein structures were predicted. Its expression pattern was analyzed, and its role in salt stress tolerance was further explored in the B73-EMS mutant. The results showed that ZmDIR11 encodes a peptide containing the Dirigent domain, and its promoter region contains ARE, MYB, MYC, STRE, LTR, and MBS structural elements, which are related to non-biological stress regulation. ZmDIR11 is predominantly expressed in the maize root system and is induced to express under salt stress. It is subcellularly localized to the endoplasmic reticulum. After salt stress treatment, the growth vigor and material accumulation of the mutant maize plants were significantly lower than those of the wild-type B73 material, and the oxidative metabolism regulation pathway, proline accumulation, chlorophyll synthesis, lignin accumulation, and Na+/K+ transport pathway were inhibited, with significantly lower related metabolic indicators than those of the wild-type B73 material. The results show that ZmDIR11 positively regulates the maize salt stress metabolic pathway and is mutated to reduce maize salt tolerance.
Abstract:
In view of the practical problems of large quantities and high production cost in the existing heavy saline alkali land improvement measures, taking the large-scale heavy saline alkali land interlayer soil formed after the large-scale, efficient and water-saving construction of Weigan River irrigation area as the research object, through the field plot test, the soil water and salt change law of different measures under winter irrigation conditions is studied. Analysis shows that all treatments, except for G1 treatment, have the highest soil moisture content at the interlayer position of 60 cm to 80 cm before and after irrigation. After three rounds of irrigation, the soil moisture content of CK treatment at 60 cm to 80 cm is 1.4% to 16.2% higher than other treatments, and the average soil moisture content at 0-100 cm is 2.3% to 15.5% higher than other treatments. At the same time, CK treatment had the highest salt content in the soil between 60 cm and 80 cm, and the desalination rate was low. After three rounds of irrigation, the desalination rate was 24.9%, only higher than G4 treatment (14.9%). Among all measures, G1 treatment had the highest desalination rate at 75.9%, followed by G6 and G3 treatments at 51.5% and 39.4%, respectively. G2 and G5 were relatively close at 38.2% and 37.4%, respectively. G4 had the lowest desalination rate at 33.9%. After two and three winter irrigations, the desalination effect of each treatment was significant, especially in the 0-20 cm soil layer, which decreased from 7.06 g/kg to 11.61 g/kg before irrigation in 2020 to 2.0 g/kg to 5.91 g/kg after irrigation in 2022. The desalination rate was between 76.8% and 382.5%, which improved the surface soil from the initial medium to moderate saline alkali soil to light to moderate saline alkali soil. The relationship between the increase in salt content and the increase in water content was inversely proportional, The research results not only reflect the blocking effect of clay interlayer on water and salt transport, but also indicate that improvement measures can promote soil water infiltration and improve soil desalination efficiency, providing data support for the selection of soil improvement measures in heavy saline alkali soil interlayer.
In view of the practical problems of large quantities and high production cost in the existing heavy saline alkali land improvement measures, taking the large-scale heavy saline alkali land interlayer soil formed after the large-scale, efficient and water-saving construction of Weigan River irrigation area as the research object, through the field plot test, the soil water and salt change law of different measures under winter irrigation conditions is studied. Analysis shows that all treatments, except for G1 treatment, have the highest soil moisture content at the interlayer position of 60 cm to 80 cm before and after irrigation. After three rounds of irrigation, the soil moisture content of CK treatment at 60 cm to 80 cm is 1.4% to 16.2% higher than other treatments, and the average soil moisture content at 0-100 cm is 2.3% to 15.5% higher than other treatments. At the same time, CK treatment had the highest salt content in the soil between 60 cm and 80 cm, and the desalination rate was low. After three rounds of irrigation, the desalination rate was 24.9%, only higher than G4 treatment (14.9%). Among all measures, G1 treatment had the highest desalination rate at 75.9%, followed by G6 and G3 treatments at 51.5% and 39.4%, respectively. G2 and G5 were relatively close at 38.2% and 37.4%, respectively. G4 had the lowest desalination rate at 33.9%. After two and three winter irrigations, the desalination effect of each treatment was significant, especially in the 0-20 cm soil layer, which decreased from 7.06 g/kg to 11.61 g/kg before irrigation in 2020 to 2.0 g/kg to 5.91 g/kg after irrigation in 2022. The desalination rate was between 76.8% and 382.5%, which improved the surface soil from the initial medium to moderate saline alkali soil to light to moderate saline alkali soil. The relationship between the increase in salt content and the increase in water content was inversely proportional, The research results not only reflect the blocking effect of clay interlayer on water and salt transport, but also indicate that improvement measures can promote soil water infiltration and improve soil desalination efficiency, providing data support for the selection of soil improvement measures in heavy saline alkali soil interlayer.
Abstract:
For the low level of automation in the citrus pruning process, based on the Internet of Things and electro-hydraulic drivng architecture ,we designed a remote control system orchard pruning robot. The robot's control system mainly constitutes a hydraulic drive module, the control module, the correspondence module, the perception module, human-phone interaction module to complete the pruning robot's joints position monitoring and remote control, with the start-stop of the hydraulic motor to complete the fruit tree mechanical pruning tasks. We used modified Denavit-Hartenberg (D-H) method to build the kinematic equation and through Matlab Robotic Toolbox, we verified the modeling of the kinematic model of the pruning robot, with Monte Carlo algorithm to visualize the theoretical workspace of the pruning mechanism. According to the different characteristics of joint movement, we selected specific sensors, controllers and hydraulic valves to design the application layer of the Internet of Things system. Based on the UART-WIFI moduel ESP8266,we established network layer of the Internet of Things system, which realizes the remote control correspondence of cell phone APP - cloud server - pruning robot. Based on the characteristics of easy to use and quick to start, we designed a human-machine interaction interface of cell phone APP, through which we can read the robot joints' positional status and send control commands to realize the robot's positional adjustment automatically. We designed a test at a open area for viewing the rapidity and accuracy of the machine prototype. The results of the test show all the positioning errors of the mobile joints are within ±0.5mm, the positioning error of each rotating joint is less than 2°and the control and adjustment time of each joint movement to the limit stroke is between 1.14s-9.21s, with good adjustment time..The experimental results show that this fruit tree pruner based on IoT architecture has a high degree of automation, a simpler mode of operation, and has a certain application value in the actual fruit tree rough pruning and profiling pruning.
For the low level of automation in the citrus pruning process, based on the Internet of Things and electro-hydraulic drivng architecture ,we designed a remote control system orchard pruning robot. The robot's control system mainly constitutes a hydraulic drive module, the control module, the correspondence module, the perception module, human-phone interaction module to complete the pruning robot's joints position monitoring and remote control, with the start-stop of the hydraulic motor to complete the fruit tree mechanical pruning tasks. We used modified Denavit-Hartenberg (D-H) method to build the kinematic equation and through Matlab Robotic Toolbox, we verified the modeling of the kinematic model of the pruning robot, with Monte Carlo algorithm to visualize the theoretical workspace of the pruning mechanism. According to the different characteristics of joint movement, we selected specific sensors, controllers and hydraulic valves to design the application layer of the Internet of Things system. Based on the UART-WIFI moduel ESP8266,we established network layer of the Internet of Things system, which realizes the remote control correspondence of cell phone APP - cloud server - pruning robot. Based on the characteristics of easy to use and quick to start, we designed a human-machine interaction interface of cell phone APP, through which we can read the robot joints' positional status and send control commands to realize the robot's positional adjustment automatically. We designed a test at a open area for viewing the rapidity and accuracy of the machine prototype. The results of the test show all the positioning errors of the mobile joints are within ±0.5mm, the positioning error of each rotating joint is less than 2°and the control and adjustment time of each joint movement to the limit stroke is between 1.14s-9.21s, with good adjustment time..The experimental results show that this fruit tree pruner based on IoT architecture has a high degree of automation, a simpler mode of operation, and has a certain application value in the actual fruit tree rough pruning and profiling pruning.
Abstract:
In order to explore the influence of dryland conversion to paddy field (dryland-to-paddy) on soil aggregate in southern red soil area, traditional dryland (HS0), dryland conversion paddy field 1 year (HS1), dryland conversion paddy field 5 year (HS5) and local traditional paddy field (CK) were selected in typical dryland-to-paddy area of Guangxi, and dry and wet screening method were used to analyze the soil aggregate properties in the tillage layer. The results showed that the contents of soil aggregates >0.25 mm (R>0.25) in mechanical aggregates and water-stable aggregates under HS0, HS1, HS5 and CK treatments were 90.0%, 94%, 95.8%, 98.1% and 81.0%, 70.6%, 76.0% and 95.4%, respectively; the mean weight diameter (MWD) was 3.35, 3.63, 3.69, 4.73 and 2.25, 0.94, 1.54, 4.63, respectively. Compared with HS0, the geometric mean diameter (GMD) of the water-stable aggregates treated with HS1 decreased by 68%. Compared with HS0, the percentage of aggregate destruction (PAD) of > 0.25mm aggregate increased first and then decreased with the years of dryling-to-paddy field, HS1 and HS5 increased by 61% and 34%, respectively, while CK significantly decreased by 76%. The results of structural equation model and random forest analysis showed that soil cation exchange capacity (CEC) and total nitrogen (TN) were important factors affecting soil aggregate stability in dryland-to-paddy field.
In order to explore the influence of dryland conversion to paddy field (dryland-to-paddy) on soil aggregate in southern red soil area, traditional dryland (HS0), dryland conversion paddy field 1 year (HS1), dryland conversion paddy field 5 year (HS5) and local traditional paddy field (CK) were selected in typical dryland-to-paddy area of Guangxi, and dry and wet screening method were used to analyze the soil aggregate properties in the tillage layer. The results showed that the contents of soil aggregates >0.25 mm (R>0.25) in mechanical aggregates and water-stable aggregates under HS0, HS1, HS5 and CK treatments were 90.0%, 94%, 95.8%, 98.1% and 81.0%, 70.6%, 76.0% and 95.4%, respectively; the mean weight diameter (MWD) was 3.35, 3.63, 3.69, 4.73 and 2.25, 0.94, 1.54, 4.63, respectively. Compared with HS0, the geometric mean diameter (GMD) of the water-stable aggregates treated with HS1 decreased by 68%. Compared with HS0, the percentage of aggregate destruction (PAD) of > 0.25mm aggregate increased first and then decreased with the years of dryling-to-paddy field, HS1 and HS5 increased by 61% and 34%, respectively, while CK significantly decreased by 76%. The results of structural equation model and random forest analysis showed that soil cation exchange capacity (CEC) and total nitrogen (TN) were important factors affecting soil aggregate stability in dryland-to-paddy field.
Abstract:
In the context of globalization, the dual pressures of population growth and resources and the environment have driven agriculture to continuously seek new paths to improve overall production efficiency and economic benefits. This study focuses on examining the role of the integrated rice farming model and Huamoxiang rice varieties in improving farmers' economic benefits, with a special focus on the two core economic indicators of planting income and planting profit. Through an analysis method that combines questionnaire surveys and econometric models, the impact of the synergistic effect of the comprehensive rice farming model and the adoption of Huamoxiang varieties on farmers' economic benefits was studied. The results show that the synergistic effect of the two significantly increases the income and profit per unit area of farmers, showing significant income increase effects and economic returns. In addition, land transfer, as an adjusting variable, further optimizes the allocation of land resources and has a positive impact on the economic benefits of integrated rice farming and Huamoxiang varieties. This study provides empirical evidence for the comprehensive rice farming model and the promotion of Huamoxiang varieties, and also provides theoretical support for improving land use efficiency and promoting sustainable agricultural development.
In the context of globalization, the dual pressures of population growth and resources and the environment have driven agriculture to continuously seek new paths to improve overall production efficiency and economic benefits. This study focuses on examining the role of the integrated rice farming model and Huamoxiang rice varieties in improving farmers' economic benefits, with a special focus on the two core economic indicators of planting income and planting profit. Through an analysis method that combines questionnaire surveys and econometric models, the impact of the synergistic effect of the comprehensive rice farming model and the adoption of Huamoxiang varieties on farmers' economic benefits was studied. The results show that the synergistic effect of the two significantly increases the income and profit per unit area of farmers, showing significant income increase effects and economic returns. In addition, land transfer, as an adjusting variable, further optimizes the allocation of land resources and has a positive impact on the economic benefits of integrated rice farming and Huamoxiang varieties. This study provides empirical evidence for the comprehensive rice farming model and the promotion of Huamoxiang varieties, and also provides theoretical support for improving land use efficiency and promoting sustainable agricultural development.
Abstract:
The promotion of whole grains is critical for enhancing food security and improving public health in China. This study analyzes consumer preferences and willingness to pay for six attributes of black rice, based on data from a survey of 408 consumers and using a choice experiment method. The results reveal that consumers exhibit strong preferences and high willingness to pay for food safety attributes of black rice, including green food certification and food quality certification. In contrast, there is no significant preference for other attributes, such as brand, taste, and sales channels. Additionally, consumer perception of the nutritional value of black rice generally positively affects consumer preferences for black rice, with most significant impact observed for green food certification. Lastly, higher-income consumers demonstrate a preference for brand and taste attributes. Our findings suggest a series of policy implications, including enhancing food safety regulation, increasing public education on food safety, raising public awareness about the nutritional value of black rice, and offering differentiated black rice products based on market heterogeneity.
The promotion of whole grains is critical for enhancing food security and improving public health in China. This study analyzes consumer preferences and willingness to pay for six attributes of black rice, based on data from a survey of 408 consumers and using a choice experiment method. The results reveal that consumers exhibit strong preferences and high willingness to pay for food safety attributes of black rice, including green food certification and food quality certification. In contrast, there is no significant preference for other attributes, such as brand, taste, and sales channels. Additionally, consumer perception of the nutritional value of black rice generally positively affects consumer preferences for black rice, with most significant impact observed for green food certification. Lastly, higher-income consumers demonstrate a preference for brand and taste attributes. Our findings suggest a series of policy implications, including enhancing food safety regulation, increasing public education on food safety, raising public awareness about the nutritional value of black rice, and offering differentiated black rice products based on market heterogeneity.
Abstract:
To investigate the influence of low frequency electric field with different intensities on the quality change and moisture migration of superchilled tilapia meat during storage. Low frequency electric fields with intensities of 600 V/m, 1500 V/m, and 3000 V/m were selected as test conditions. Indicators such as drip loss rate, water holding capacity, hardness, color, TVB-N content, and water migration of superchilled tilapia meat were measured during storage. The results showed that low frequency electric field could effectively suppress drip loss rate, maintain water holding capacity, with greater intensity resulting in more significant effects. From the fourth day, drip loss rate of samples treated with 3000 V/m electric field was significantly lower than that of control group (P<0.05), and water holding capacity was significantly higher (P<0.05). Meanwhile, low frequency electric field could inhibit color deterioration, hardness decrease, TVB-N content increase, extend the shelf life; By the sixteenth day, the increase in TVB-N content of control group was about 1.6~3.0 times higher than that of electric field groups. According to low field nuclear magnetic resonance analysis, as storage time increases, the water in tilapia meat migrated from immobilized water to free water, while low frequency electric field could suppress water migration, and the higher electric field intensity, the more significant effect. The above results indicated that low frequency electric field with electric field intensity of 3000 V/m had the best effect on maintaining the quality of superchilled tilapia meat.
To investigate the influence of low frequency electric field with different intensities on the quality change and moisture migration of superchilled tilapia meat during storage. Low frequency electric fields with intensities of 600 V/m, 1500 V/m, and 3000 V/m were selected as test conditions. Indicators such as drip loss rate, water holding capacity, hardness, color, TVB-N content, and water migration of superchilled tilapia meat were measured during storage. The results showed that low frequency electric field could effectively suppress drip loss rate, maintain water holding capacity, with greater intensity resulting in more significant effects. From the fourth day, drip loss rate of samples treated with 3000 V/m electric field was significantly lower than that of control group (P<0.05), and water holding capacity was significantly higher (P<0.05). Meanwhile, low frequency electric field could inhibit color deterioration, hardness decrease, TVB-N content increase, extend the shelf life; By the sixteenth day, the increase in TVB-N content of control group was about 1.6~3.0 times higher than that of electric field groups. According to low field nuclear magnetic resonance analysis, as storage time increases, the water in tilapia meat migrated from immobilized water to free water, while low frequency electric field could suppress water migration, and the higher electric field intensity, the more significant effect. The above results indicated that low frequency electric field with electric field intensity of 3000 V/m had the best effect on maintaining the quality of superchilled tilapia meat.
Abstract:
In order to solve the problem of lack of theoretical basis in the design and simulation analysis of Zizania latifolia processing, harvesting and other equipment, research on the characteristics of Zizania latifolia materials were studied. Static load compression experiments were carried out on Zizania latifolia using a texture apparatus to obtain the stiffness, damage strength and modulus of elasticity of Zizania latifolia under different compression directions and compression rates, and the microstructure of Zizania latifolia was obtained by using a scanning electron microscope (SEM) to analyze the intrinsic mechanism of the variability of the mechanical properties of Zizania latifolia under different compression directions. The experimental results showed that Zizania latifolia was anisotropic material. The average stiffness values of Zizania latifolia in the X axis, Y axis and Z axis were 37.88 N/mm, 36.66 N/mm and 50.82 N/mm respectively. The average damage strengths were 0.74 MPa, 0.72 MPa, 0.88 MPa, respectively. And the average modulus of elasticity was 1.73 MPa, 1.61 MPa, 2.33 MPa, respectively. The compression direction had a highly significant effect on the stiffness, elastic modulus and damage strength of Zizania latifolia (p<0.001), and the effect of compression rate on stiffness, elastic modulus and damage strength was not significant in the range of compression rate from 30 to 70 mm/min (p>0.05). The microstructural features in the X-axis and Y-axis directions were similar and different from those in the Z-axis direction. The distribution of pores along the X-axis and Y-axis directions is the reason for the small values of compressive mechanical properties in these two directions. The results of this paper could provide theoretical reference for the packaging, storage and mechanized production of Zizania latifolia.
In order to solve the problem of lack of theoretical basis in the design and simulation analysis of Zizania latifolia processing, harvesting and other equipment, research on the characteristics of Zizania latifolia materials were studied. Static load compression experiments were carried out on Zizania latifolia using a texture apparatus to obtain the stiffness, damage strength and modulus of elasticity of Zizania latifolia under different compression directions and compression rates, and the microstructure of Zizania latifolia was obtained by using a scanning electron microscope (SEM) to analyze the intrinsic mechanism of the variability of the mechanical properties of Zizania latifolia under different compression directions. The experimental results showed that Zizania latifolia was anisotropic material. The average stiffness values of Zizania latifolia in the X axis, Y axis and Z axis were 37.88 N/mm, 36.66 N/mm and 50.82 N/mm respectively. The average damage strengths were 0.74 MPa, 0.72 MPa, 0.88 MPa, respectively. And the average modulus of elasticity was 1.73 MPa, 1.61 MPa, 2.33 MPa, respectively. The compression direction had a highly significant effect on the stiffness, elastic modulus and damage strength of Zizania latifolia (p<0.001), and the effect of compression rate on stiffness, elastic modulus and damage strength was not significant in the range of compression rate from 30 to 70 mm/min (p>0.05). The microstructural features in the X-axis and Y-axis directions were similar and different from those in the Z-axis direction. The distribution of pores along the X-axis and Y-axis directions is the reason for the small values of compressive mechanical properties in these two directions. The results of this paper could provide theoretical reference for the packaging, storage and mechanized production of Zizania latifolia.
Abstract:
Aiming at the existing freshwater fish fish body dissection device is mainly hand-feeding, single-machine operation, processing efficiency is low, can not meet the mechanisation, automation of fish body dissection processing needs, etc., this paper takes Hypophthalmichthys moritrix as the object of study, carries out the research on the key components of the clamping-type Hypophthalmichthys moritrix body dissection device, and test-produces the clamping-type Hypophthalmichthys moritrix body dissection device, and test validates it. The experimental verification was carried out. The Hypophthalmichthys moritrix body dissection device consists of a frame, a fish conveyor, a fish body clamping mechanism, a fish body dissection mechanism, and a cleaning mechanism; through the compression test of the fish body, we obtained the minimum limiting pressure of the fish body; through the analysis of the force of the fish body clamping and conveying process and the dissection process, we explored the conditions of satisfying the clamping and conveying process as well as the magnitude of the force of the knife discs with different rotational directions on the fish. Taking Hypophthalmichthys moritrix acceptability score and cutting loss rate as evaluation indexes, a one-way test was carried out on the influencing factors such as initial spacing of clamping rollers, Cutterhead sectioning high, rotating speed of cutter, etc., to explore the effects of the factors on the cutting effect of Hypophthalmichthys moritrix. Through orthogonal test, it was determined that the order of the factors affecting the fish body cutting effect was: Cutter speed of cutter > Cutter sectioning high > Initial spacing of pinch rollers; when the initial spacing of pinch rollers was 20mm, the rotating speed of cutter sectioning high was 135mm, and the rotating speed of cutter speed was 1400r/min, the Hypophthalmichthys moritrix body was smooth in section, and the integrity of the flesh was high, and the average value of the acceptability score was 9.48, and the rate of loss of sectioning was 0.11%, and the processing efficiency can be up to 8.0 fish/min. The results of this paper can provide a reference for the research and development of bulk freshwater fish body dissection device and the design of automated pre-treatment processing line for freshwater fish.
Aiming at the existing freshwater fish fish body dissection device is mainly hand-feeding, single-machine operation, processing efficiency is low, can not meet the mechanisation, automation of fish body dissection processing needs, etc., this paper takes Hypophthalmichthys moritrix as the object of study, carries out the research on the key components of the clamping-type Hypophthalmichthys moritrix body dissection device, and test-produces the clamping-type Hypophthalmichthys moritrix body dissection device, and test validates it. The experimental verification was carried out. The Hypophthalmichthys moritrix body dissection device consists of a frame, a fish conveyor, a fish body clamping mechanism, a fish body dissection mechanism, and a cleaning mechanism; through the compression test of the fish body, we obtained the minimum limiting pressure of the fish body; through the analysis of the force of the fish body clamping and conveying process and the dissection process, we explored the conditions of satisfying the clamping and conveying process as well as the magnitude of the force of the knife discs with different rotational directions on the fish. Taking Hypophthalmichthys moritrix acceptability score and cutting loss rate as evaluation indexes, a one-way test was carried out on the influencing factors such as initial spacing of clamping rollers, Cutterhead sectioning high, rotating speed of cutter, etc., to explore the effects of the factors on the cutting effect of Hypophthalmichthys moritrix. Through orthogonal test, it was determined that the order of the factors affecting the fish body cutting effect was: Cutter speed of cutter > Cutter sectioning high > Initial spacing of pinch rollers; when the initial spacing of pinch rollers was 20mm, the rotating speed of cutter sectioning high was 135mm, and the rotating speed of cutter speed was 1400r/min, the Hypophthalmichthys moritrix body was smooth in section, and the integrity of the flesh was high, and the average value of the acceptability score was 9.48, and the rate of loss of sectioning was 0.11%, and the processing efficiency can be up to 8.0 fish/min. The results of this paper can provide a reference for the research and development of bulk freshwater fish body dissection device and the design of automated pre-treatment processing line for freshwater fish.
Abstract:
To explore the etiology of a serious infectious disease occurred in Rana grylio at a farm in Sichuan province, pathological examination and pathogen isolation were carried out for the diseased frogs. The isolated pathogen was identified by transmission electron microscopy, PCR detection and phylogenetic analysis. External clinical signs included swelling of limbs and ulcerations on body surface. The dead frog exhibited enlarged liver, spleen and kidney. Based on histopathological observation, we found that liver, spleen, kidney and other organs had damages with obvious degeneration and necrosis focus. The carp epithelioma papulosum cyprini ( EPC ) cell line inoculated with diseased samples under 25℃ and exhibited typical cytopathic effects ( CPE ) after four days exhibited typical cytopathic effects ( CPE ) ，such as rounding and shedding, with the TCID50 of 10-4.12/0.1 mL. Transmission electron microscopic observation showed that the virus was regular hexagon with capsule arrayed in crystallines, and the diagonal diameter was about 165 nm. PCR by using major capsid protein (MCP) gene specific primers was performed on the internal tissues of infected frogs and the EPC cells with CPE, and the results were positive. Phylogenetic analysis based on MCP gene sequences indicated that the sequences of isolated virus had over 99% identity to ranavirus, and belonged to FV3-like. The study confirmed that the isolated virus, named TSL210813, belonged to ranavirus, which was the cause of diseased R. grylio.
To explore the etiology of a serious infectious disease occurred in Rana grylio at a farm in Sichuan province, pathological examination and pathogen isolation were carried out for the diseased frogs. The isolated pathogen was identified by transmission electron microscopy, PCR detection and phylogenetic analysis. External clinical signs included swelling of limbs and ulcerations on body surface. The dead frog exhibited enlarged liver, spleen and kidney. Based on histopathological observation, we found that liver, spleen, kidney and other organs had damages with obvious degeneration and necrosis focus. The carp epithelioma papulosum cyprini ( EPC ) cell line inoculated with diseased samples under 25℃ and exhibited typical cytopathic effects ( CPE ) after four days exhibited typical cytopathic effects ( CPE ) ，such as rounding and shedding, with the TCID50 of 10-4.12/0.1 mL. Transmission electron microscopic observation showed that the virus was regular hexagon with capsule arrayed in crystallines, and the diagonal diameter was about 165 nm. PCR by using major capsid protein (MCP) gene specific primers was performed on the internal tissues of infected frogs and the EPC cells with CPE, and the results were positive. Phylogenetic analysis based on MCP gene sequences indicated that the sequences of isolated virus had over 99% identity to ranavirus, and belonged to FV3-like. The study confirmed that the isolated virus, named TSL210813, belonged to ranavirus, which was the cause of diseased R. grylio.
Abstract:
In order to rapidly and accurately obtain crop growth information such as plant height and volume in the field environment, this paper takes peanuts as the research object and adopts 3D LiDAR perception technology to obtain peanut point cloud data in the field. After registration, denoising, and other processing, a three-dimensional point cloud model is constructed. The point cloud plant segmentation method based on KD-TREE is used to segment individual peanut plants from the point cloud data. The convex hull algorithm is used to estimate plant volume, and the rotating caliper method is utilized to extract plant height and maximum canopy width, thereby obtaining peanut growth information. Point cloud data of peanut plants at three different growth stages were collected in a peanut planting experimental area. The proposed method was used to carry out verification tests for individual peanut plant segmentation and extraction of plant height and maximum canopy width. The accuracy of growth information acquisition was investigated, and recall and precision rates were used to evaluate the results. Experimental results showed that the recall and precision rates of individual peanut plant segmentation in the field could reach over 85%, indicating that the proposed method has good accuracy and completeness for segmenting peanut point cloud data in the field. The extracted parameters such as peanut plant height and maximum canopy width were compared with manual measurements. The average absolute percentage errors of plant height in the three different growth stages were 6.2705%, 4.3675%, and 4.9859%, respectively, and the maximum canopy widths were 7.1140%, 5.6063%, and 4.5410%, respectively. The root mean square errors of plant height were 0.0096m, 0.0152m, and 0.0271m, respectively, and the root mean square errors of the maximum canopy width were 0.0110m, 0.0201m, and 0.0203m, respectively. The linear regression determination coefficients of plant height data were 0.88797, 0.95101, and 0.84183, respectively, and the linear regression determination coefficients of maximum canopy width data were 0.93431, 0.93179, and 0.92717, respectively. These results verify the accuracy and feasibility of using point clouds to measure peanut growth data, enabling high-precision, non-destructive extraction of peanut phenotypic parameters. The research results provide important technical support for peanut cultivation and breeding.
In order to rapidly and accurately obtain crop growth information such as plant height and volume in the field environment, this paper takes peanuts as the research object and adopts 3D LiDAR perception technology to obtain peanut point cloud data in the field. After registration, denoising, and other processing, a three-dimensional point cloud model is constructed. The point cloud plant segmentation method based on KD-TREE is used to segment individual peanut plants from the point cloud data. The convex hull algorithm is used to estimate plant volume, and the rotating caliper method is utilized to extract plant height and maximum canopy width, thereby obtaining peanut growth information. Point cloud data of peanut plants at three different growth stages were collected in a peanut planting experimental area. The proposed method was used to carry out verification tests for individual peanut plant segmentation and extraction of plant height and maximum canopy width. The accuracy of growth information acquisition was investigated, and recall and precision rates were used to evaluate the results. Experimental results showed that the recall and precision rates of individual peanut plant segmentation in the field could reach over 85%, indicating that the proposed method has good accuracy and completeness for segmenting peanut point cloud data in the field. The extracted parameters such as peanut plant height and maximum canopy width were compared with manual measurements. The average absolute percentage errors of plant height in the three different growth stages were 6.2705%, 4.3675%, and 4.9859%, respectively, and the maximum canopy widths were 7.1140%, 5.6063%, and 4.5410%, respectively. The root mean square errors of plant height were 0.0096m, 0.0152m, and 0.0271m, respectively, and the root mean square errors of the maximum canopy width were 0.0110m, 0.0201m, and 0.0203m, respectively. The linear regression determination coefficients of plant height data were 0.88797, 0.95101, and 0.84183, respectively, and the linear regression determination coefficients of maximum canopy width data were 0.93431, 0.93179, and 0.92717, respectively. These results verify the accuracy and feasibility of using point clouds to measure peanut growth data, enabling high-precision, non-destructive extraction of peanut phenotypic parameters. The research results provide important technical support for peanut cultivation and breeding.
Display Method:
Abstract:
Effects of soaking temperature,cultivation temperature and watering frequency on the growth characteristics and nutrition of mung bean sprout were investigated. Growth characteristics and nutrition of mung bean sprout were significantly affected by soaking temperature,cultivation temperature and watering frequency (P<0.05). When the bean was soaked at higher temperature (40℃),body weight of the cultivated mung bean sprout was heavier,hypocotyl was longer,contents of free amino acid (FAA),water soluble sugar (WSS) and γ-aminobutyric acid (GABA) were higher. The hypocotyl was longer while the diameter was smaller when the bean was cultivated in the relatively higher temperature (30-35℃). When the watering frequency decreased,weight,hypocotyl length and diameter decreased,WSS content decreased first and then increased,FAA content increased first and then decreased,GABA content was fluctuated. The optimal germination conditions of mung bean sprout were soaking bean at 40℃ for 5 h,with cultivation temperature of 25-30℃ and watering once per hour.
Effects of soaking temperature,cultivation temperature and watering frequency on the growth characteristics and nutrition of mung bean sprout were investigated. Growth characteristics and nutrition of mung bean sprout were significantly affected by soaking temperature,cultivation temperature and watering frequency (P<0.05). When the bean was soaked at higher temperature (40℃),body weight of the cultivated mung bean sprout was heavier,hypocotyl was longer,contents of free amino acid (FAA),water soluble sugar (WSS) and γ-aminobutyric acid (GABA) were higher. The hypocotyl was longer while the diameter was smaller when the bean was cultivated in the relatively higher temperature (30-35℃). When the watering frequency decreased,weight,hypocotyl length and diameter decreased,WSS content decreased first and then increased,FAA content increased first and then decreased,GABA content was fluctuated. The optimal germination conditions of mung bean sprout were soaking bean at 40℃ for 5 h,with cultivation temperature of 25-30℃ and watering once per hour.
Abstract:
In this study,we investigated the effect of bio-floating bed on growth and muscle quality of grass carp (Ctenopharyngodon idellus) and blunt snout bream(Megalobrama amblycephala) in ponds.Two modes of culture ponds were chosen:one equipped with bio-floating bed was the experimental pond,and the other without beds was the control pond.At the end of the experiment,we measured the growth parameters,the muscle conventional nutrients,water holding capacity (WHC),and texture characteristics using biochemical and physical methods.The results showed that the final weight of fish cultured in the experimental pond was higher than that in the control pond.The hepatic somatic index of grass carp (1.77%) in the experimental pond was significantly lower than that of the control (2.47%).The condition factors of grass carp and blunt snout bream (1.73 and 2.56,respectively) were significantly higher than those of the control (1.64 and 2.40,respectively).There was no significant difference in the eviscerated weight of both carp and bream between the experimental (91.06 and 88.28,respectively) and the control (89.22 and 88.49,respectively) ponds.The drop loss (14.49% and 10.69,respectively) and water loss rate (17.52% and 10.34%,respectively) of the experimental grass carp and blunt snout bream were significantly lower than those of the control.The cooked rate of the experimental fish was significantly higher than the control.The muscle crude fat content (1.89%) and crude protein content (14.60%) of grass carp in the experimental ponds were significantly higher than those of the control (1.54% and 13.46%),whereas muscle water content (81.68%) of the experimental fish was significantly lower than that (82.65%) of the control.There is no significant difference in muscle ash content between the two groups.Unlike grass carp,only muscle crude protein content (17.23%) of the experimental bream was significantly higher than that (15.90%) of the control.The muscular hardness,gumminess,and chewiness of the experimental carp (5 298.10 g,2 450.78 g and 770.78 g,respectively) were significantly higher than those of the control (3 226.79 g,1 881.43 g and 602.80 g,respectively).The resilience (0.31) and cohesion (0.48) of experimental carp were significantly lower than those (0.43 and 0.58,respectively) of the control.However,only the muscular springiness of the blunt snout bream in the experimental pond was significantly higher than that in the control pond.
In this study,we investigated the effect of bio-floating bed on growth and muscle quality of grass carp (Ctenopharyngodon idellus) and blunt snout bream(Megalobrama amblycephala) in ponds.Two modes of culture ponds were chosen:one equipped with bio-floating bed was the experimental pond,and the other without beds was the control pond.At the end of the experiment,we measured the growth parameters,the muscle conventional nutrients,water holding capacity (WHC),and texture characteristics using biochemical and physical methods.The results showed that the final weight of fish cultured in the experimental pond was higher than that in the control pond.The hepatic somatic index of grass carp (1.77%) in the experimental pond was significantly lower than that of the control (2.47%).The condition factors of grass carp and blunt snout bream (1.73 and 2.56,respectively) were significantly higher than those of the control (1.64 and 2.40,respectively).There was no significant difference in the eviscerated weight of both carp and bream between the experimental (91.06 and 88.28,respectively) and the control (89.22 and 88.49,respectively) ponds.The drop loss (14.49% and 10.69,respectively) and water loss rate (17.52% and 10.34%,respectively) of the experimental grass carp and blunt snout bream were significantly lower than those of the control.The cooked rate of the experimental fish was significantly higher than the control.The muscle crude fat content (1.89%) and crude protein content (14.60%) of grass carp in the experimental ponds were significantly higher than those of the control (1.54% and 13.46%),whereas muscle water content (81.68%) of the experimental fish was significantly lower than that (82.65%) of the control.There is no significant difference in muscle ash content between the two groups.Unlike grass carp,only muscle crude protein content (17.23%) of the experimental bream was significantly higher than that (15.90%) of the control.The muscular hardness,gumminess,and chewiness of the experimental carp (5 298.10 g,2 450.78 g and 770.78 g,respectively) were significantly higher than those of the control (3 226.79 g,1 881.43 g and 602.80 g,respectively).The resilience (0.31) and cohesion (0.48) of experimental carp were significantly lower than those (0.43 and 0.58,respectively) of the control.However,only the muscular springiness of the blunt snout bream in the experimental pond was significantly higher than that in the control pond.
2013,32(4):48-54, DOI: 1000-2421（2013）04-0048-07
Abstract:
The spatial distribution of Valley County land use degree in 2009 was studied and the spatial autocorrelation of land use degree and its driving factors in different scales were analyzed.A spatial autoregressive model and geographically weighted regression model was established from the perspective of global local.The results showed that there was a certain spatial autocorrelation in land use degree and its driving factors with scale effect.Spatial regression model could estimate the overall parameter of various factors while geographically weighted regression model could give the local parameter of various factors.Scales of geographical weighted regression model could reflect the detailed geographical information to some extent.
The spatial distribution of Valley County land use degree in 2009 was studied and the spatial autocorrelation of land use degree and its driving factors in different scales were analyzed.A spatial autoregressive model and geographically weighted regression model was established from the perspective of global local.The results showed that there was a certain spatial autocorrelation in land use degree and its driving factors with scale effect.Spatial regression model could estimate the overall parameter of various factors while geographically weighted regression model could give the local parameter of various factors.Scales of geographical weighted regression model could reflect the detailed geographical information to some extent.
Abstract:
pCB302-3 is a plant mini-binary stable transformation vector.To investigate the transient expression of pCB302-3 vector in plant,GFP was inserted into pCB302-3 vector as a reporter gene,and various factors including density of Agrobacterium cell,supplementation of gene silencing suppression p19 and days post infiltration were optimized based on agroinfiltration method in Nicotiana benthamiana leaves.Results showed that high levels of GFP expression were observed in N.benthamiana leaves 3-5 d after infiltration by Agrobacterium cell suspension contained pCB302-3-GFP with an optical density （D600） of 0.8-1.0 co-infiltrated with p19 gene.
pCB302-3 is a plant mini-binary stable transformation vector.To investigate the transient expression of pCB302-3 vector in plant,GFP was inserted into pCB302-3 vector as a reporter gene,and various factors including density of Agrobacterium cell,supplementation of gene silencing suppression p19 and days post infiltration were optimized based on agroinfiltration method in Nicotiana benthamiana leaves.Results showed that high levels of GFP expression were observed in N.benthamiana leaves 3-5 d after infiltration by Agrobacterium cell suspension contained pCB302-3-GFP with an optical density （D600） of 0.8-1.0 co-infiltrated with p19 gene.
2012,31(1):16-22, DOI: 1000-2421（2012）01-0016-07
Abstract:
Nitrogen is one of essential nutrients for plant growth.Under the N deficiency at different time points，the dynamic changes of the expression of genes and activity of enzymes related to nitrogen assimilation in rice were investigated.The results showed that the concentrations of ammonium and nitrate significantly reduced under the N deficiency.Under the N deficiency for a short time，the expression level of genes including NR1, NR2, NiR2,GS2,Fd-GOGAT,GDH2,GDH3 in the shoots as well as NR1,NR2,GDH4 in the roots were up-regulated,and then their expression level decreased after a long time under the N deficiency.Along with the extension of time under the N deficiency,the GS,Fd-GOGAT activities in whole plants,NR activity in shoots and NADH-GOGAT activity in roots decreased while the NADPH-GDH activity in shoots increased.In roots the activities of NR,GDH increased at first and then decreased，while in shoots the NiR activity was just the opposite.Re-supplied N after 7 days of N deficiency,the transcriptional expression level and enzyme activities of NR,NiR,GS,GOGAT,GDH restored,and expression level of some genes increased as well.
Nitrogen is one of essential nutrients for plant growth.Under the N deficiency at different time points，the dynamic changes of the expression of genes and activity of enzymes related to nitrogen assimilation in rice were investigated.The results showed that the concentrations of ammonium and nitrate significantly reduced under the N deficiency.Under the N deficiency for a short time，the expression level of genes including NR1, NR2, NiR2,GS2,Fd-GOGAT,GDH2,GDH3 in the shoots as well as NR1,NR2,GDH4 in the roots were up-regulated,and then their expression level decreased after a long time under the N deficiency.Along with the extension of time under the N deficiency,the GS,Fd-GOGAT activities in whole plants,NR activity in shoots and NADH-GOGAT activity in roots decreased while the NADPH-GDH activity in shoots increased.In roots the activities of NR,GDH increased at first and then decreased，while in shoots the NiR activity was just the opposite.Re-supplied N after 7 days of N deficiency,the transcriptional expression level and enzyme activities of NR,NiR,GS,GOGAT,GDH restored,and expression level of some genes increased as well.
Abstract:
Twenty-two fungi with whole genome sequence published and the antiSMASH database were used to classify and annotate the gene clusters of synthesizing secondary metabolites of plant pathogenic fungi with different nutritional types in order to clarify the role of secondary metabolites of plant pathogenic fungi with different nutritional types in infecting plants and the differences in gene clusters. The results showed that the type and number of gene clusters of synthesizing secondary metabolites of hemi-biotrophs and necrotrophs fungi were higher than that of biotrophs fungi. The results of further analyzing the gene clusters of synthesizing secondary metabolites of non-ribosomal peptide synthetase,polyketide synthase and terpene showed that the number of NRPS gene clusters,PKS gene clusters and terpene gene clusters in hemi-biotrophs and necrotrophs pathogenic fungi were higher than that in biotrophs pathogenic fungi as well. It will provide an important theoretical basis for further analyzing the function of the gene cluster of synthesizing secondary metabolites of different trophic types of fungi and identifying new drug targets. Analyzing the gene clusters of synthesizing secondary metabolites in fungi and clarifying the differences in gene clusters of synthesizing secondary metabolites of different nutrition types of fungi is conducive to the better development of medicaments for preventing and controlling novel action targets of plant diseases.
Twenty-two fungi with whole genome sequence published and the antiSMASH database were used to classify and annotate the gene clusters of synthesizing secondary metabolites of plant pathogenic fungi with different nutritional types in order to clarify the role of secondary metabolites of plant pathogenic fungi with different nutritional types in infecting plants and the differences in gene clusters. The results showed that the type and number of gene clusters of synthesizing secondary metabolites of hemi-biotrophs and necrotrophs fungi were higher than that of biotrophs fungi. The results of further analyzing the gene clusters of synthesizing secondary metabolites of non-ribosomal peptide synthetase,polyketide synthase and terpene showed that the number of NRPS gene clusters,PKS gene clusters and terpene gene clusters in hemi-biotrophs and necrotrophs pathogenic fungi were higher than that in biotrophs pathogenic fungi as well. It will provide an important theoretical basis for further analyzing the function of the gene cluster of synthesizing secondary metabolites of different trophic types of fungi and identifying new drug targets. Analyzing the gene clusters of synthesizing secondary metabolites in fungi and clarifying the differences in gene clusters of synthesizing secondary metabolites of different nutrition types of fungi is conducive to the better development of medicaments for preventing and controlling novel action targets of plant diseases.
Abstract:
The development of Golden Rice to date has taken longer than anticipated.It has been proven to have the potential to assist in the alleviation of an important public health problem,vitamin A deficiency,affecting millions.Complying with the highly precautionary,and now proven unnecessary,UN Cartagena Protocol for Biosafety has impeded scientific progress and scientific collaboration,particularly by delaying the selection of phenotypes grown in the open field.So far therefore,Golden Rice has not been able to assist in combatting vitamin A deficiency,identified by the UN as an important public health target for 25 years,and which continues to cause preventable deaths and blindness.However,the inventor’s original vision of the donation of the technology to assist the resource poor who want to benefit from it remains firm and achievable,subject to continuing philanthropic and public sector funding.
The development of Golden Rice to date has taken longer than anticipated.It has been proven to have the potential to assist in the alleviation of an important public health problem,vitamin A deficiency,affecting millions.Complying with the highly precautionary,and now proven unnecessary,UN Cartagena Protocol for Biosafety has impeded scientific progress and scientific collaboration,particularly by delaying the selection of phenotypes grown in the open field.So far therefore,Golden Rice has not been able to assist in combatting vitamin A deficiency,identified by the UN as an important public health target for 25 years,and which continues to cause preventable deaths and blindness.However,the inventor’s original vision of the donation of the technology to assist the resource poor who want to benefit from it remains firm and achievable,subject to continuing philanthropic and public sector funding.
2013,32(5):124-133, DOI: 1000-2421（2013）05-0124-10
Abstract:
Bacterial canker is a devastating disease of kiwifruit. In recent years,the disease is showing a tendency to outbreak in such countries as Italy and New Zealand,where kiwifruit is a major crop,and has the trends to further spread worldwide,which will be a serious threat to the development of the kiwifruit industry. Based on the latest research reports, this paper summarized the symptoms,pathogen identification,rapid detection methods,virulence differences,infected mechanism,epidemiology and control technology of the disease. Meanwhile,the future research prospect of kiwifruit bacterial canker was also discussed in order to reduce the loss and risk of the kiwifruit industry.
Bacterial canker is a devastating disease of kiwifruit. In recent years,the disease is showing a tendency to outbreak in such countries as Italy and New Zealand,where kiwifruit is a major crop,and has the trends to further spread worldwide,which will be a serious threat to the development of the kiwifruit industry. Based on the latest research reports, this paper summarized the symptoms,pathogen identification,rapid detection methods,virulence differences,infected mechanism,epidemiology and control technology of the disease. Meanwhile,the future research prospect of kiwifruit bacterial canker was also discussed in order to reduce the loss and risk of the kiwifruit industry.
2014,33(2):139-144, DOI: 1000-2421（2014）02-0139-06
Abstract:
Algae are lower photosynthetic autotrophs which have close relationship with agricultural activities.With the deep understanding of physiological and ecological characteristics,algae have used more and more widelyin the practice of agricultural activities.This paper reviews the application of algaeas a resourcein agricultural activities including improvement of agricultural environment,utilized as food or food additives and health care products,as well as feed or bait.
Algae are lower photosynthetic autotrophs which have close relationship with agricultural activities.With the deep understanding of physiological and ecological characteristics,algae have used more and more widelyin the practice of agricultural activities.This paper reviews the application of algaeas a resourcein agricultural activities including improvement of agricultural environment,utilized as food or food additives and health care products,as well as feed or bait.
Abstract:
Soil salinity is a major environmental constraint to agricultural productivity.It is a complex network for plant adaptation to salt stress,and it is still a great challenge to improve crop salt tolerance.Mechanisms of SOS signal transduction pathway on Na+ exclusion and compartmentation,the regulation of microRNA and transcription factors involved in salt stress were reviewed.It will provide a fundamental understanding and knowledge for studying salt resistance and breeding salt tolerance in plants.
Soil salinity is a major environmental constraint to agricultural productivity.It is a complex network for plant adaptation to salt stress,and it is still a great challenge to improve crop salt tolerance.Mechanisms of SOS signal transduction pathway on Na+ exclusion and compartmentation,the regulation of microRNA and transcription factors involved in salt stress were reviewed.It will provide a fundamental understanding and knowledge for studying salt resistance and breeding salt tolerance in plants.
2012,31(2):258-264, DOI: 1000-2421（2012）02-0258-07
Abstract:
The characteristics and principles of seed treatment methods commonly used in crop production such as physical,chemical,biotic pesticides,seed priming,seed coating and seed pelleting were summerized.The biological effects of seed treatment were mainly summarized and analyzed.Meanwhile,the trend of crops seed treatment was prospected.
The characteristics and principles of seed treatment methods commonly used in crop production such as physical,chemical,biotic pesticides,seed priming,seed coating and seed pelleting were summerized.The biological effects of seed treatment were mainly summarized and analyzed.Meanwhile,the trend of crops seed treatment was prospected.
Abstract:
In order to overcome the transition，field operation, and standardized batch production difficulties of the existing track cargo vehicle in mountainous orchard, as well as to raise the utilization rate, the mountain orchard detachable unidirectional traction double track cargo vehicle was developed. This paper introduced the whole machine structure, the wire rope diameter selection，the minimum track inclination，the maximum track distance，the minimum track turning radius and the working principle of the rope brake device. Load experiments were carried out to test the cargo′s synthetic track function. It is indicated by calculation that the wire rope diameter should be 7.7 mm，the minimum track inclination was 5.7°, the maximum track distance was 170 m, the minimum track horizontal turning radius was 7 m, and the minimum track vertical turning radius was 2 m. Load experiment results indicated that the cargo vehicle′s uplink average speed was 0.51 m/s, the downlink average speed was 0.54 m/s, the average energy consumption was 1.235 kW·h and the effective use degree was 100%. This cargo vehicle was suitable for fruit, pesticide, chemical fertilizer and other cargo transportation in the mountain orchard. Meanwhile, it can be applied to carry the spraying machine, the shave machine and other agricultural machines.
In order to overcome the transition，field operation, and standardized batch production difficulties of the existing track cargo vehicle in mountainous orchard, as well as to raise the utilization rate, the mountain orchard detachable unidirectional traction double track cargo vehicle was developed. This paper introduced the whole machine structure, the wire rope diameter selection，the minimum track inclination，the maximum track distance，the minimum track turning radius and the working principle of the rope brake device. Load experiments were carried out to test the cargo′s synthetic track function. It is indicated by calculation that the wire rope diameter should be 7.7 mm，the minimum track inclination was 5.7°, the maximum track distance was 170 m, the minimum track horizontal turning radius was 7 m, and the minimum track vertical turning radius was 2 m. Load experiment results indicated that the cargo vehicle′s uplink average speed was 0.51 m/s, the downlink average speed was 0.54 m/s, the average energy consumption was 1.235 kW·h and the effective use degree was 100%. This cargo vehicle was suitable for fruit, pesticide, chemical fertilizer and other cargo transportation in the mountain orchard. Meanwhile, it can be applied to carry the spraying machine, the shave machine and other agricultural machines.
Abstract:
Using Mesorhizobium sp.S-15 and Paenibacillus sp.S-17 as experimental strains.After cell disruption,NH4OAc extraction,H2O2 solution digestion or without any pre-treatment,K+ content in the fermentation broth of potassium solubilizing bacteria was determined with flame photometer.The efficiency of K solubilizing by potassium solubilizing bacteria in the culture medium was calculated.The results showed that the standard curves of the three kinds of K series of standard solutions were similar with the R2 values of 0.994 4,0.999 7 and 0.999 8,respectively.After digested by H2O2 solution,concentration of K+ was detected.The efficiency of two strains was 101.1% and 125.1%,significantly higher than that of other groups.The efficiency of potassium solubilizing detected after H2O2 digestion well reflected potassium solubilization of bacteria.
Using Mesorhizobium sp.S-15 and Paenibacillus sp.S-17 as experimental strains.After cell disruption,NH4OAc extraction,H2O2 solution digestion or without any pre-treatment,K+ content in the fermentation broth of potassium solubilizing bacteria was determined with flame photometer.The efficiency of K solubilizing by potassium solubilizing bacteria in the culture medium was calculated.The results showed that the standard curves of the three kinds of K series of standard solutions were similar with the R2 values of 0.994 4,0.999 7 and 0.999 8,respectively.After digested by H2O2 solution,concentration of K+ was detected.The efficiency of two strains was 101.1% and 125.1%,significantly higher than that of other groups.The efficiency of potassium solubilizing detected after H2O2 digestion well reflected potassium solubilization of bacteria.
Abstract:
Flow cytometry and spectrophotometry were used to measure the cell numbers and absorbances of three common cultures including Escherichia coli S17-1, Synechocystis sp. PCC 6803 and Bacillius subtilis 168 at different concentrations in the laboratory. Then the absorbance values and cell numbers of each culture were compared. The function relationship between absorbance and cell numbers was established. The results showed that the absorbance value and cell numbers of the three common cultures in the laboratory were significantly positively correlated with the concentration at the certain concentration. It was verified that the absorbance value of the culture can reflect the number of cells during the culture process using the fitting function. The relationship between the absorbance and cell number of three strains including Escherichia coli S17-1, Synechocystis sp. PCC 6803 and Bacillius subtilis 168 was established. It will provide the foundation for developing biological experiments to determine the cell number and downstream molecules in the culture using a spectrophotometer.
Flow cytometry and spectrophotometry were used to measure the cell numbers and absorbances of three common cultures including Escherichia coli S17-1, Synechocystis sp. PCC 6803 and Bacillius subtilis 168 at different concentrations in the laboratory. Then the absorbance values and cell numbers of each culture were compared. The function relationship between absorbance and cell numbers was established. The results showed that the absorbance value and cell numbers of the three common cultures in the laboratory were significantly positively correlated with the concentration at the certain concentration. It was verified that the absorbance value of the culture can reflect the number of cells during the culture process using the fitting function. The relationship between the absorbance and cell number of three strains including Escherichia coli S17-1, Synechocystis sp. PCC 6803 and Bacillius subtilis 168 was established. It will provide the foundation for developing biological experiments to determine the cell number and downstream molecules in the culture using a spectrophotometer.
Abstract:
This review of the safety assessment of genetically modified (GM) crops is focused primarily on the process and progress in the United States (US). It reviews the development of the safety evaluation process from the Asilomar conference in 1975 considering issues relevant to recombinant DNA technology,to discussions between the US government,academic and industrial scientists between 1984 and 1994 when the first GM crops were being field tested and evaluated commercial release for food and feed production. International guidelines were also reviewed for consistency with the US system. The overall process includes consideration of information relating to history of safe or unsafe human and exposure to the gene source and expressed proteins. The primary considerations of safety for dietary proteins are whether or not some consumers are sensitized and have IgE antibodies against the protein encoded by the transgene or whether the transgene represents a risk of eliciting celiac disease. The process considers potential toxic effects of expressed proteins as well as potential impacts on human and animal nutrition. The process in the US is consistent with Codex Alimentarius recommendations. It follows a science based process based on justifiable hypotheses. To date there is no evidence that GM crops approved in the US have harmed human or animal consumers. The evaluation takes into account genetic and environmental variation in products produced by plant varieties and is intended to maintain the standard that foods developed from GM plants are intended to be as safe as non-GM genetically similar varieties.
This review of the safety assessment of genetically modified (GM) crops is focused primarily on the process and progress in the United States (US). It reviews the development of the safety evaluation process from the Asilomar conference in 1975 considering issues relevant to recombinant DNA technology,to discussions between the US government,academic and industrial scientists between 1984 and 1994 when the first GM crops were being field tested and evaluated commercial release for food and feed production. International guidelines were also reviewed for consistency with the US system. The overall process includes consideration of information relating to history of safe or unsafe human and exposure to the gene source and expressed proteins. The primary considerations of safety for dietary proteins are whether or not some consumers are sensitized and have IgE antibodies against the protein encoded by the transgene or whether the transgene represents a risk of eliciting celiac disease. The process considers potential toxic effects of expressed proteins as well as potential impacts on human and animal nutrition. The process in the US is consistent with Codex Alimentarius recommendations. It follows a science based process based on justifiable hypotheses. To date there is no evidence that GM crops approved in the US have harmed human or animal consumers. The evaluation takes into account genetic and environmental variation in products produced by plant varieties and is intended to maintain the standard that foods developed from GM plants are intended to be as safe as non-GM genetically similar varieties.
2023,42(2):1-8, DOI: 10.13300/j.cnki.hnlkxb.2023.02.001
Abstract:
Cattle industry is an important part of animal husbandry and a pillar industry for agriculture and rural development in China.However， the prevalence of important infectious diseases in cattle seriously restricts the healthy and sustainable development of cattle industry and public health security.With the continuous expansion of domestic and foreign trade related to cattle， its impact is on the rise.In this paper， the epidemic characterization， control status and challenges of important bovine diseases in China were reviewed from three aspects， including important infectious diseases， emerging infectious diseases and re-emerging infectious diseases.It is considered that the prevalence of important infectious diseases in cattle is associated with complex and changing natural， social， and economic factors， which is characterized by following aspects： unclear epidemiological background， the continuous emergence of new diseases， the re-emergence of some controlled diseases， the frequent co-infection with multiple pathogens， diagnosis， and treatment difficulties etc.Finally， based on the current internal and external challenges for the effective prevention and control of important bovine infectious diseases， the prevention and control suggestions were put forward， in order to provide reference for the effective prevention and control of important bovine infectious diseases in China.
Cattle industry is an important part of animal husbandry and a pillar industry for agriculture and rural development in China.However， the prevalence of important infectious diseases in cattle seriously restricts the healthy and sustainable development of cattle industry and public health security.With the continuous expansion of domestic and foreign trade related to cattle， its impact is on the rise.In this paper， the epidemic characterization， control status and challenges of important bovine diseases in China were reviewed from three aspects， including important infectious diseases， emerging infectious diseases and re-emerging infectious diseases.It is considered that the prevalence of important infectious diseases in cattle is associated with complex and changing natural， social， and economic factors， which is characterized by following aspects： unclear epidemiological background， the continuous emergence of new diseases， the re-emergence of some controlled diseases， the frequent co-infection with multiple pathogens， diagnosis， and treatment difficulties etc.Finally， based on the current internal and external challenges for the effective prevention and control of important bovine infectious diseases， the prevention and control suggestions were put forward， in order to provide reference for the effective prevention and control of important bovine infectious diseases in China.
2012,31(1):127-132, DOI: 1000-2421（2012）01-0127-06
Abstract:
Post-harvest strawberries are susceptible to the decay of fruit and deterioration of quality due to pathogenic fungi infections,a main factor leading to economic losses for both growers and retailers.With the increase of strawberries planting in China,it is urgent to effectively reduce post-harvest rots of strawberry fruits.In this review,new management developments for controlling fungal diseases in post-harvest strawberry were summarized in terms of physical,chemical and biological approaches,which can help to extend the on-shelf time of strawberry fruits.
Post-harvest strawberries are susceptible to the decay of fruit and deterioration of quality due to pathogenic fungi infections,a main factor leading to economic losses for both growers and retailers.With the increase of strawberries planting in China,it is urgent to effectively reduce post-harvest rots of strawberry fruits.In this review,new management developments for controlling fungal diseases in post-harvest strawberry were summarized in terms of physical,chemical and biological approaches,which can help to extend the on-shelf time of strawberry fruits.
2011,30(5):613-617, DOI: 1000-2421（2011）05-0613-05
Abstract:
Pot experiment was conducted to study the effects of spraying different micronutrients and amino acids into the surface of leaves on yield and quality of Chinese cabbage (Brassica rapa L.).The results showed that methionine,zinc,molybdenum,boron and glycine could increase yield of Chinese cabbage.The treatments of spraying methionine,zinc and molybdenum increased yield of Chinese cabbage significantly.All treatments could reduce the nitrate content of Chinese cabbage with the highest decrease of 35.0% compared with the control.Molybdenum,boron,zinc and methionine might reduce nitrate content of Chinese cabbage significantly.Experiment also indicated that glycine,proline and selenium could both increase the contents of vitamin C,soluble sugar and soluble protein of Chinese cabbage.Therefore,spraying micronutrient or amino acids into the surface of leaves is a good application for increasing yield,reducing nitrate content and improving quality of Chinese cabbage.
Pot experiment was conducted to study the effects of spraying different micronutrients and amino acids into the surface of leaves on yield and quality of Chinese cabbage (Brassica rapa L.).The results showed that methionine,zinc,molybdenum,boron and glycine could increase yield of Chinese cabbage.The treatments of spraying methionine,zinc and molybdenum increased yield of Chinese cabbage significantly.All treatments could reduce the nitrate content of Chinese cabbage with the highest decrease of 35.0% compared with the control.Molybdenum,boron,zinc and methionine might reduce nitrate content of Chinese cabbage significantly.Experiment also indicated that glycine,proline and selenium could both increase the contents of vitamin C,soluble sugar and soluble protein of Chinese cabbage.Therefore,spraying micronutrient or amino acids into the surface of leaves is a good application for increasing yield,reducing nitrate content and improving quality of Chinese cabbage.
2012,31(5):569-573, DOI: 1000-2421（2012）05-0569-05
Abstract:
Hydroponic experiments of strawberry were conducted with three formulations of nutrient solution to select the best formulations for soilless cultivation of strawberry.Several main characteristics of growth including the fresh weight and dry weight of overground plant and root，the growth of crown，the photosynthetic and quality of strawberry，the diameter of staminate flower，the growth amass were investigated．The results showed that the effect of nutrient solution with the content of calcium nitrate tetrahydrate,potassium nitrate,ammonium dihydrogen phosphate,magnesium sulfate and ammonium nitrate at 295,303,62,246,0 mg/L on the growing status and fruit quality of strawberry are better than that of the other 2 treatments.This nutrient solution formula was the most propitious for the growth of ‘Jingyao’ strawberry and the enhancement of the fruit quality among the three different treatnments.That is,it facilitated the growth of strawberry in alimentation growth periods,and the leaves of ‘Jingyao’ strawberry was larger and thicker with a dark-green color,and the diameter of the pedicel was also larger. In addition,the nutrient solution formula was also conducive to the flowering promotion and the reproductive growth of strawberry,and resultes showed that the single fruit weight,yield and fruit quality is the best comparing to the other treatments.The results of this study provided academic and technological basis for establishing high yield and quality of strawberry in greenhouse substrate culture of irrigation and nitrogen application system.
Hydroponic experiments of strawberry were conducted with three formulations of nutrient solution to select the best formulations for soilless cultivation of strawberry.Several main characteristics of growth including the fresh weight and dry weight of overground plant and root，the growth of crown，the photosynthetic and quality of strawberry，the diameter of staminate flower，the growth amass were investigated．The results showed that the effect of nutrient solution with the content of calcium nitrate tetrahydrate,potassium nitrate,ammonium dihydrogen phosphate,magnesium sulfate and ammonium nitrate at 295,303,62,246,0 mg/L on the growing status and fruit quality of strawberry are better than that of the other 2 treatments.This nutrient solution formula was the most propitious for the growth of ‘Jingyao’ strawberry and the enhancement of the fruit quality among the three different treatnments.That is,it facilitated the growth of strawberry in alimentation growth periods,and the leaves of ‘Jingyao’ strawberry was larger and thicker with a dark-green color,and the diameter of the pedicel was also larger. In addition,the nutrient solution formula was also conducive to the flowering promotion and the reproductive growth of strawberry,and resultes showed that the single fruit weight,yield and fruit quality is the best comparing to the other treatments.The results of this study provided academic and technological basis for establishing high yield and quality of strawberry in greenhouse substrate culture of irrigation and nitrogen application system.
2011,30(4):488-493, DOI: 1000-2421（2011）04-0488-06
Abstract:
The morphological variations and discriminant methods of Channa argus (♂)，C.maculata (♀) and their hybrid were studied using traditional morphometrics and the truss network analysis.Body color of C.argus,C.maculata and their hybrid were observed.The results showed significant differences between C.argus and C.maculata from stripe at top of head,side and base of caudal fin,and the hybrid resembled C.maculata from body color.Among eleven meristic characters,the numbers of soft ray of pelvic fin were consistent in these three species,and the numbers of soft ray of pectoral fin deviated from its male parent’s species.The other meristic characters were within the range of its parent’s,the average hybrid index was calculated to be 53.45.The chi-square analysis of meristic characters showed that:there were significant differences(P<0.05) or greater significant differences(P<0.01) between C.argus and C.maculata except the number of pectoral fin rays; greater significant differences(P<0.01) between C.argus and the hybrid except the number of tail fin rays,gill rakers,lateral line scales and scales below lateral line; and significant differences(P<0.05) or greater significant differences(P<0.01) between C.maculata and the hybrid except the number of tail fin rays and gill rakers.Among meristic characters,the number of dorsal fin rays,lateral line scales and scales above lateral line can be used as preliminary indicators to determine the three species.Among ten measurable characters,the average hybrid index was calculated to be 73.90,indicating the measurable character inclined to its male parent’s species (C.argus).Cluster analysis,discriminant analysis and principal component analysis were applied to the measurable character data and the truss network data.The results indicated that the hybrid resembled C.argus from body shape,and there were greater morphological differences among C.argus,C.maculata and their hybrid.Differences between them involved the entire body.Three species could be distinguished by using the 3 formulae established with discriminant analysis which the discrimination accuracy was 100.0%.
The morphological variations and discriminant methods of Channa argus (♂)，C.maculata (♀) and their hybrid were studied using traditional morphometrics and the truss network analysis.Body color of C.argus,C.maculata and their hybrid were observed.The results showed significant differences between C.argus and C.maculata from stripe at top of head,side and base of caudal fin,and the hybrid resembled C.maculata from body color.Among eleven meristic characters,the numbers of soft ray of pelvic fin were consistent in these three species,and the numbers of soft ray of pectoral fin deviated from its male parent’s species.The other meristic characters were within the range of its parent’s,the average hybrid index was calculated to be 53.45.The chi-square analysis of meristic characters showed that:there were significant differences(P<0.05) or greater significant differences(P<0.01) between C.argus and C.maculata except the number of pectoral fin rays; greater significant differences(P<0.01) between C.argus and the hybrid except the number of tail fin rays,gill rakers,lateral line scales and scales below lateral line; and significant differences(P<0.05) or greater significant differences(P<0.01) between C.maculata and the hybrid except the number of tail fin rays and gill rakers.Among meristic characters,the number of dorsal fin rays,lateral line scales and scales above lateral line can be used as preliminary indicators to determine the three species.Among ten measurable characters,the average hybrid index was calculated to be 73.90,indicating the measurable character inclined to its male parent’s species (C.argus).Cluster analysis,discriminant analysis and principal component analysis were applied to the measurable character data and the truss network data.The results indicated that the hybrid resembled C.argus from body shape,and there were greater morphological differences among C.argus,C.maculata and their hybrid.Differences between them involved the entire body.Three species could be distinguished by using the 3 formulae established with discriminant analysis which the discrimination accuracy was 100.0%.
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