Abstract:The structural imbalance of microbial communities in soil is one of the important factors for the occurrence of obstacles for tomato continuous cropping. This article reviewed the changing characteristics of microbial communities in soil and the reconstruction techniques in tomato continuous cropping to study the mechanism of obstacles for tomato continuous cropping and promote the sustainable development of the tomato industry. The decrease in microbial diversity in soil under tomato continuous cropping and the structure shift of microbial communities in soil from "bacterial" soil to "fungal" soil are the main reasons for the occurrence of obstacles for tomato continuous cropping. Rotation and intercropping， grafting， soil disinfection， and application of organic fertilizer can reconstruct the structure of microbial communities in soil under tomato continuous cropping， helping to reduce the harm of obstacles for continuous cropping， especially rotation and intercropping of leguminous crops are more conducive to reducing the harm of obstacles for tomato continuous cropping. So far， studies have found that functional microorganisms including Arthrobacter， Bacillus， Pseudomonas， Solirubrobacter， and Trichoderma spp. are beneficial in overcoming obstacles for tomato continuous cropping. The development of bio-organic fertilizers combined with organic fertilizers for reconstructing the microbial communities in farmland soil is a highly promising technical measure for biological prevention and control of obstacles for continuous cropping. However， how to ensure the colonization， survival， and large-scale reproduction of functional microorganisms in the application of bio-organic fertilizers in different environments is an important bottleneck problem that urgently needs to be solved in this technology.

Abstract:The soil fertility and structural and functional characteristics of microbial community in rhizospheres of tomatoes during different growth periods were compared to construct an eco-cultivation system for tomato production with high yield and high quality and utilize the resources of beneficial microbes. The soil fertility and structural and functional characteristics of microbial （bacterial， fungal） community in rhizospheres of tomato at the stage of seedling， flower and bud differentiation， and fruiting were analyzed based on conventional and modern high-throughput sequencing techniques. The results showed that there were more abundant sources of carbon， nitrogen， and phosphorus in the rhizospheres of of tomatoes at the stage of fruiting in tomato. The structure and function of soil microbial community in rhizospheres of tomatoes had undergone significant changes during different growth periods. Among them， norank_f_norank_o_norank_c_KD4-96， norank_f_A4b and Bryobacter were the unique dominant bacterial genus in the rhizospheres of tomatoes at the stage of seedling.TM7a and Saccharomonospora were the unique dominant bacterial genus in rhizospheres of tomatoes at the stage of flower and bud differentiation. Only Gemmatimonas was the unique dominant bacterial genus in rhizospheres of tomatoes at the stage of fruiting. Moreover， Powellomyces was the unique dominant fungal genus in rhizospheres of tomatoes at the stage of seedling， Apiotrichum and unclassified_f_Chytridiaceae were the unique dominant fungal genera in rhizospheres of tomatoes at the stage of flower and bud differentiation， and Alternaria was the unique dominant fungal genus in rhizospheres of tomatoes at the stage of fruiting. It is indicated that specific microbial communities were formed in rhizospheres of tomatoes at different stages of growth. Microorganisms enriched in rhizospheres of tomatoes at the stage of seedling mainly produce hormones for plant growth. The enrichments of soil microorganisms in rhizospheres of tomatoes at the stage of flower and bud differentiation primarily improve resistance for plants. Microorganisms enriched in rhizospheres of tomatoes at the stage of fruiting chiefly promote the nutrient cycling in soil.

Abstract:The associated cultivation modes of tomato and lettuce， amaranth， cabbage， mint and onion were set up. The effects of different associated crops on the fertility of the rhizosphere soil and the diversity of bacteria and fungi of the main tomato were analyzed based on high-throughput sequencing technology to study the mechanism of the effects of different associated crops on the fertility and health of the rhizosphere soil of the main tomato， and provide theoretical basis and technical support for constructing the ecological cultivation model of tomato. The results showed that the associated cultivation with four associated crops except of cabbage significantly increased the activity of soil enzymes including aminopeptidases and phosphatase， and microbial biomass carbon， nitrogen and phosphorus in the rhizosphere soil of the main tomato plant. Although the associated cultivation did not enrich the microbial diversities in the rhizosphere soil of the main tomato plant， it changed the microbial abundance ratio in the rhizosphere soil of the main tomato plant. At phylum level， the associated cultivation increased the abundance ratio of Proteobacteria， Firmicutes and Patescibactera bacteria. At genus level， norank f. Microscillaceae， norank_f. norank. o. Vicinamibacterales， Bacillus， norank.f. Gemmatimonadaceae， and Altererythrobacter were the top ten unique dominant bacteria in rhizospheres of tomatoes associated with different crops. In addition， the associated cultivation changed the diversity and abundance of fungi in the rhizosphere soil of the main tomato plants to varying degrees， and enriched the dominant fungi of the phylum Chlamydomonas， Basidiomycetes， and Phyllomycetes. At the same time， it enriched the dominant fungi including unclassified o Sordariales， Olpidium， and Conoxybe， Phallemonium， unclassified o Pleosporales， unclassified o Boletales， and Sodiomyces， and increased the abundance ratio of Chaetomium as well. It is indicated that the associated cultivation of lettuce， amaranth， mint and onion in tomato contributes to improve the fertility of tomato rhizosphere soil and maintain the health of rhizosphere microenvironment soil in varying degrees. Among them， the effect of associated cultivation of lettuce and mint on improving soil fertility and maintaining soil health is better than that of corresponding cabbage， amaranth and onion.

Abstract:The effects of different associated crops on the structure of endophytic microbial community in tomato roots were analyzed to study the diversity and structure of endophytic microbial community in tomato roots， and to explore and develop the functions of beneficial microorganisms. Five associated crops and monoculture treatments including tomato associated lettuce（A）， amaranth（B）， cabbage（C）， chive（D）， mint（E） and monoculture（F） were set under the same conditions. The structures of endophytic microbial community in tomato roots were analyzed with MiSeq high-throughput sequencing technology. The results showed that Streptomyces， Burkholderia-Caballeronia-Paraburkholderia， Devosia， Nocardioides and Massilia were the top five common dominant endophytic bacterial genera in roots of tomatoes under associated and monoculture systems. However， Noviherbaspirillum was the special dominant endophytic bacterial genus in roots of tomatoes under tomato companioned lettuce （A） associated system； Meanwhile， Actinoplanes was also the unique dominant endophytic bacterial genera in roots of tomatoes under tomato companioned amaranth （B） associated system. Moreover， Herpetosiphon was the special dominant endophytic bacterial genera in roots of tomatoes under tomato companioned chive （D） associated system.Furthermore， Microbacterium was the special dominant endophytic bacterial genus in roots of tomatoes under tomato companioned mint （E）. By contrast， Bacillus， Marmoricola and Glycomyces were the unique dominant endophytic bacterial genera in roots of tomatoes in monoculture system（F）. In addition， Olpidium， unclassified_o_Sordariales and unclassified_p_Ascomycota were the common dominant endophytic fungal genera in roots of tomatoes under associated and monoculture systems. And lmmersiella was the special dominant endophytic fungal genera in roots of tomatoes under tomato companioned lettuce （A） associated system； Meanwhile， Candida， unclassified_c_Agaricomycetes， Phialemonium were the unique dominant endophytic fungal genera in roots of tomatoes under tomato companioned amaranth （B）； Geminibasidium， Plectosphaerella and Rhizophagus were the unique dominant endophytic fungal genera in roots of tomatoes under tomato companioned cabbage （C）； unclassified_p_Chytridiomycota， unclassified_f_Ceratobasidiaceae， Ceratorhiza， unclassified_o_Boletales， and unclassified_p_Basidiomycota were the special dominant endophytic fungal genera in roots of tomatoes under tomato companioned chive （D）； By contrast， Gibberella was the unique dominant endophytic fungal genera in roots of tomatoes under monoculture system （F）. It is indicated that the compositions of dominant endophytic bacteria and fungi at phylum or genera level in tomato roots can be altered by associated cultivation with other crops in comparison with the monoculture of tomato. The special dominant endophytic bacterial and fungal genera can be enriched by associated with other crops. The composition of specific dominant endophytic microorganisms enriched by associated cultivation has the potential to enhance the resistance of tomato to environmental biological or abiotic stresses.

Abstract:Tomatoes were routinely planted in the same field for 3 consecutive years.Using sterile deionized water （CK） as a control，and wood vinegar diluted by 300 times （A），600 times （B），and 900 times （C）.The antibacterial activity of wood vinegar with different dilutions and its effect on the root growth and the structure of bacterial and fungal communities in the rhizosphere of tomato under continuous cropping system were studied to provide theoretical basis and technical support for the sustainable development of the tomato industry using wood vinegar.The results showed that the antibacterial activities of wood vinegars with different dilution significantly inhibited pathogens of bacterial wilt and fusarium wilt.Among the wood vinegars with three dilutions，irrigation with wood vinegar diluted by 600 times was not only beneficial to the growth of the roots，but also helped to improve the diversity of bacteria and fungi in the rhizosphere of tomato under continuous cropping system.Compared with the control （CK），wood vinegars with different dilutions reduced the relative abundance of Actinobacteria to varying degrees，and increased the relative abundance of beneficial microorganisms including Acidobacter，Ascomycota，Neocospora，Aspergillus，Penicillium，Trichoderma，Chaetomium，Trichoderma and Fusarium.It is indicated that wood vinegar has a significant inhibitory effect on the pathogenic microorganisms of tomato bacterial wilt and fusarium wilt.Irrigation with diluted wood vinegar is beneficial to the root growth of tomato and improves the microecology of the rhizosphere of tomato under continuous cropping system.Among them，the improvement effect of wood vinegar diluted by 600 times （B） was the best.

Abstract:In order to explore whether the biomimetic and endogenous chemical agent ethylicin can be used to prevent and control sugarcane disease and whether it can promote the growth of sugarcane， the indoor antibacterial tests， toxicity tests， and barrel planting application tests were carried out to evaluate the prevention and control effect of ethylicin on sugarcane leaf scald caused by Xanthomonas albilineans （Ashby） Dawson. At the same time， the agronomic traits， biomass， and other phenotypes of sugarcane treated with different concentrations of ethylicin were determined by pot planting experiments， and the growth promoting effects were evaluated by combining the physiological characteristics such as photosynthesis， root system， and stress resistance. The results of toxicity test showed that the toxicity regression equation of ethylicin was y=26.29x-30.29， the correlation coefficient R² was 0.948 9， and the effective middle mass concentration EC₅₀ was 1 132.43 μg/mL. The results of disease prevention and control and growth promotion experiments showed that the 1 000-fold dilution of 80% ethylicin was the best. Under this treatment， no sugarcane leaf scald positive plant was detected after 42 days of application， while the positive rate of the control （CK） was 100%. Moreover， compared with CK， the chlorophyll content in sugarcane leaves increased by 24.93%， the net photosynthetic rate increased by 64.97%， and the root activity increased by 62.44%， indicating a significant growth promoting effect. In addition， compared with CK， the antioxidant enzyme activities such as SOD， POD， and CAT under this treatment increased by 21.32%， 44.32%， and 54.32% respectively. The content of soluble sugar， soluble protein， proline and other osmotic regulating substances in leaves increased by 17.40%， 17.39%， and 17.78%， respectively， while the content of MDA decreased by 22.74%， alleviating membrane lipid peroxidation， maintaining cell membrane stability and enhancing the stress resistance of sugarcane. In summary， the 1 000-fold dilution of 80% ethylicin has a good control effect on sugarcane leaf scald and has a promoting effect on sugarcane growth.

Abstract:In order to explore the gene expression pattern at transcriptional level of tomato after inoculated with Meloidogyne incognita， transcriptome sequencing was performed on tomato root at 6 h， 12 h， 24 h and 48 h after inoculated with 2nd instar larvae of root-knot nematode. The key transcription factor related to the tomato response to the infection of M. incognita were analyzed and the sequencing results were verified by quantitative real-time PCR. The results showed that 350， 390， 580， 1 154 genes were differentially expressed at 6 h， 12 h， 24 h and 48 h after inoculation， and 11， 11， 19 and 50 transcription factors were differentially expressed， respectively. They belonged to 15 transcription factor families， of which MYB family and bHLH family are the most abundant with 20 genes， followed by ERF family with 19 genes， WRKY family with 15 genes， and bZIP family with 9 genes. Further studies showed that the transcription factors of ERF，WRKY，MYB and bHLH family were the most differentially expressed. Solyc03g005520， Solyc02g094270 and Solyc09g066350 were significantly up regulated and the log₂FC at 48 h after inoculation was 9.16， 6.49 and 6.33， respectively. Solyc03g005520， Solyc02g094270 and Solyc09g066350 were significantly down regulated， and log₂FC at 48 h after inoculation was -2.60，-1.72 and -1.70，respectively. The results of qRT-PCR analysis showed that the expression trend of six randomly selected genes was consistent with the sequencing results. The results of this study suggest that the transcription factors of ERF， WRKY and bHLH family may be involved in the interaction between tomato and M. incognita， and play an important regulatory role in tomato response to the infection of M. incognita.

Abstract:A meteorological forecasting model for the migration of Spodoptera frugiperda was preliminarily established based on the weather forecast platform and the medium-short term numerical forecast of European Centre for Medium-Range Weather Forecasts （ECMWF） to accurately predict the migration routes of pests and use weather forecasting technology to predict migratory pests. The atmospheric circulation situation and low-level wind dynamic were used to accurately forecast the migration routes， migration time including the first day of emergence and the day with a peak number and falling zone of Spodoptera frugiperda. A detailed review of two typical forecasting cases of the migration of Spodoptera frugiperda in 2021 was conducted. The typical weather processes and meteorological factor fields of the migratory layer of Spodoptera frugiperda， which migrated northward to Hubei Province in spring （first day of sighting） and southward to Hubei Province in autumn （peak day） in 2021， were analyzed. The HYSPLIT route model was used to simulate the backward routes of migration. The prediction conclusion was validated using data from monitoring Spodoptera frugiperda in the field and from monitoring lamp and migration routes. The results showed that the forecasting conclusions of two typical prediction cases were in good agreement with data from monitoring Spodoptera frugiperda in the field and from monitoring lamp， and the scenario simulation of migration routes. The forecasting of the migration time， falling fields and routes was basically correct， which verified the feasibility of using the weather forecast technologies to predict migratory pests.

Abstract:High-throughput sequencing of 16S rRNA from endosymbiotic bacteria in potato leaves under drought stress was performed with Illumina Novaseq sequencing technology to understand the changes in the composition and structure of endosymbiotic bacteria in potatoes under drought stress. The effects of drought stress on the composition， structure， and diversity of endosymbiotic bacteria in potato leaves were studied. The results showed that 1 548 and 2 006 taxonomic sequences were obtained from potato leaves under normal watering and drought stress， respectively. Among them， 287 were unique OTUs under normal watering and 769 were unique OTUs under drought stress. Under drought stress， the abundance of the endosymbiotic bacteria candidatus Portiera and Arsenophonus decreased by 95.9% and 68.1% compared with that under normal watering， while the abundance of Muribaculaceae， Lachnospira， Lactobacillus， Lachnospiraceae_NK4A136_group， Rhizobium， Helicobacter， Streptococcus and Desulfovibrio increased by 203.8%，152.4%，81.8%，89.7%，285.6%，1 428.0%，112.0% and 148.4% respectively under drought stress compared with that under normal watering. The Shannon index and Simpson index under drought stress were significantly higher than that under normal watering， while the ACE index and Chao1 index under drought stress were not significantly different from that under normal watering. It is indicated that drought stress can affect the composition of endosymbiotic bacterial communities in potatoes. Under drought stress， the endosymbiotic dominant bacteria Actinomycetota and Bacillota were enriched， and the relative abundance of Burkholderiaceae bacteria increased， which may be the positive response of potato to drought stress.

Abstract:A reasonable layout of urban park green space （UGS） is an important prerequisite for ensuring equal access to green space resources for urban residents and improving the living level of the city. In traditional UGS planning， the evaluation of urban comprehensive park services based on indicators including green space rate or green coverage rate is difficult to accurately and quantitatively evaluate the balance of the layout of urban comprehensive park. A two-step floating catchment area method based on improved multi-transport mode was proposed for the central urban area of Hefei City. The path planning model of Gaode map， combined with the methods of bivariate local spatial autocorrelation， Lorenz curve and Gini coefficient was used to analyze the accessibility and supply and demand of urban comprehensive parks under different time thresholds based on the signaling data of mobile phone. The rationality of the layout of comprehensive parks in the central urban area was further revealed. The results showed that the traditional method of calculating the accessibility and two-step mobile search model was improved by utilizing the signaling data of mobile phone and the path planning data of Gaode map as data sources. The accessibility evaluation framework of urban comprehensive parks at a micro scale was established， which can accurately evaluate the accessibility of urban comprehensive parks. The accessibility of comprehensive parks in the central urban area of Hefei City is significantly different in space. The areas with high accessibility are usually distributed in the new urban area and the surrounding areas of the comprehensive parks. With the increase of time threshold， the spatial distribution of accessibility level presents a balanced trend. Only about 5% of the residential grids in the central urban area of Hefei City are in the state of supply and demand matching under the time threshold of 15 minutes and 30 minutes. Nearly 7% of the residential grids are in a significant mismatch between supply and demand， mainly concentrated in the western part of the old city and the northern part of lakeside area. It is indicated that the density of residential areas and the number of comprehensive parks is important factors that affect the matching of supply and demand. Optimizing the accessibility of urban transportation to increase the threshold for recreational travel in comprehensive parks in residential areas can significantly promote the overall rationality of the spatial distribution of urban comprehensive parks. It will provide important guidance for optimizing the layout of comprehensive parks in the central urban area of Hefei City in the future.

Abstract:The distribution of potential suitability of tobacco areas in Hubei Province was simulated by using the CLDAS data set of land data assimilation system of China Meteorological Administration from 2008 to 2020 and other environmental factors， and the actual planting sites based on the maximum entropy model （MaxEnt） to comprehensively evaluate the effects of ecological climate factors on the growth and development of tobacco leaves in Hubei Province. The dominant environmental factors that affect its distribution were studied. The results showed that MaxEnt model had a high accuracy in predicting the suitability distribution of tobacco areas with AUC of 0.854. Altitude （650-1 750 m）， soil type （yellow soil）， minimum temperature at the rosette stage （8.9-15.0 ℃）， temperature in the prosperously growing period （16.0-22.9 ℃）， and temperature in the maturing period （18.8-25.6 ℃） were the dominant environmental factors affecting the distribution of tobacco areas in Hubei Province. The highly suitable areas of tobacco are mainly distributed in Enshi， Shiyan， southern Xiangyang and southeastern Yichang， accounting for 18.2% of the total area of Hubei Province. The climate characteristics of 80% of the region are at an altitude of 7 00 to 1 350 m， with an average minimum temperature of 11.2 to 14.5 ℃ in the cluster period， an average temperature of 19.2 to 22.8 ℃ in the peak period， and an average temperature of 22.0 to 25.4 ℃ in the mature period. Among all environmental factors， altitude plays a decisive role， while temperature is an important meteorological factor affecting the growth and development of tobacco. It is indicated that the results are basically consistent with the actual spatial distribution of tobacco growing areas in Hubei Province. It will provide a theoretical reference for the scientific planting and layout of tobacco in Hubei Province.

Abstract:A single root ultimate tensile test and a root soil interface pull-out friction test were conducted using a TY-8000 tensile machine and the root system of Hippophae rhamnoides， a pioneer shrub for soil and water conservation in the arid and semi-arid areas of Inner Mongolia to investigate the effect of mowing measures on the mechanical properties of roots. The effect of mowing on the soil fixation mechanical properties of Hippophae rhamnoides root system was analyzed. The results showed that the ultimate anti-tension and resistance tensile force of a single root were positively correlated with the diameter as a power function under the conditions of mowing and non-mowing when the measured root diameter was 0-5.0 mm. The ultimate tensile strength of a single root and the tensile shear strength of the root soil interface were negatively correlated with the diameter as a power function. In the representative root diameter class of Hippophae rhamnoides ranging from 0.5 to 1.5 mm， the average ultimate anti-tension of a single root in mowing was 31% higher than that in non-mowing. The average ultimate tensile strength of a single root increased by 37% and the average pull-out shear strength increased by 30%. It is indicated that the diameter has an impact on the strength of tensile and shear of the Hippophae rhamnoides root system， and the properties of tensile and shear have been improved after the mowing treatment.

Abstract:Amino acids， vitamin E and lipids are three classes of metabolites with antioxidant activity. GC-MS， UPLC， and LC-MS/MS were used to detect the relative content of three types of metabolites in the fruits of six Citrus varieties during the ripening process to analyze the dynamic changes of amino acids， vitamin E， and lipids during the ripening process of citrus fruits and evaluate the antioxidant activity of citrus. The results showed that citrus fruits mainly accumulated serine， proline， and aspartic acid， while threonine was particularly abundant during the green fruit stage of citrus. The total content of nine amino acids in green pulp of C. chuana ‘Bendizao’ （BDZ） during the green fruit stage was the highest. For vitamin E， α- tocopherol is the main isomeric form in citrus， which accumulates abundantly in mature colored pericarp. Additionally， citrus fruits did not accumulate δ- tocopherol， and γ- tocopherol only accumulated in the colored pericarp of citrus. A total of 8 major categories （176 species） of lipids were identified and showed significant characteristics of spatiotemporal distribution in citrus fruits， with phosphatidylcholine being the main form of lipids in citrus. It was found that some amino acids are highly positively correlated with lipids through correlation analysis of the content of three types of metabolites in citrus fruits. It will have a guiding significance for the improvement of quality in citrus varieties.

Abstract:The differences in fruit quality of ‘Cocktail’ grapefruit between the mode of facility cultivation and open cultivation （CK） were studied to improve the quality of ‘Cocktail’ grapefruit in Hubei Province. The results showed that the single fruit weight， transverse and longitudinal diameter and fruit shape index of facility cultivation were larger than those of CK. There was no significant difference in peel hardness during fruit development. There was a significant difference in peel hardness between facility cultivation and CK from 227 days after anthesis. Facility cultivation significantly increased the content of soluble solid in fruits to 10.43%. The content of titratable acid and Vc in facility cultivation was higher than that in CK. The results of GC-MS analysis showed that facility cultivation increased the content of sucrose in fruits to 49.63 mg/g. The results of real-time quantitative PCR analysis showed that facility cultivation increased the content of sucrose in fruits by upregulating the expression levels of CsSPS2， CsSUS2 and CsSUS4. It is indicated that facility cultivation can improve the fruit quality of ‘Cocktail’ grapefruit.

Abstract:6-year-old ‘Hongmeiren’ citrus hybrid trees grafted on trifoliate orange （Poncirus trifoliata） rootstock were used to study the effects of different leaf/fruit ratios on the physiological and biochemical characteristics of autumn shoot leaves of citrus under protected cultivation.Three leaf/fruit ratios including low （LFR60） medium （LFR80） and high （LFR100） were set up.The physiological and biochemical indexes including the contents of mineral elements，metabolites of carbon and nitrogen，activities of key enzymes and antioxidant enzymes in the metabolism of carbon and nitrogen in autumn shoot leaves were determined.The results showed that the content of phosphorus，potassium，magnesium，starch in autumn shoot leaves of LFR80 and LFR100 were significantly higher than that of LFR60.The content of malondialdehyde，proline，ascorbic acid in autumn shoot leaves of LFR80 and LFR100 were significantly lower than that of LFR60.The activity of β-amylase，nitrate reductase，glutamine synthetase，ascorbate peroxidase in autumn shoot leaves of LFR80 and LFR100 were significantly higher than that of LFR60.The content of nutrients in autumn shoot leaves of LFR80 and LRF100 were more sufficient and the degree of stress was lower.It is indicated that controlling the leaf/fruit ratio of ‘Hongmeiren’ hybrid citrus under protected cultivation between 80 and 100 is beneficial for balancing vegetative and reproductive growth，delaying leaf senescence，and maintaining robust tree.

Abstract:The cDNA from cassava Arg7 leaves was used to amplify MePP2CAa gene with RT-PCR to study the role of the protein phosphatase 2C （PP2C） gene in the response of cassava to abiotic stress.The sequence，self-activation activity，and the activity of promoter of the MePP2CAa gene were analyzed bioinformatically.The expression patterns of MePP2CAa gene under different stress and hormone treatments，and its interaction with ABA receptor PYLs were studied.The results showed that the total length of MePP2CAa gene was 1 311 bp，encoding 436 amino acids with the structural domain characteristics of the PP2C family.The protein sequence of MePP2CAa had the highest homology with that of PP2C in Hevea rubber and Jatropha curcas，with 78.95% and 74.09%，respectively，and conserved at the C-terminus.The results of real time fluorescence quantitative PCR showed that the expression level of MePP2CAa gene in cassava storage roots was significantly higher than that in stems and leaves.Mannitol，NaCl，ABA，MeJA，low temperature and SA treatment significantly induced the expression of MePP2CAa gene.The results of analyzing the cis-acting elements of promoters showed that the promoter of MePP2CAa gene included ABRE responsive element，MeJA responsive element，and drought induced element，etc.The results of yeast two hybridization showed that MePP2CAa interacted with MePYL1.It is indicated that the MePP2CAa gene may respond to the abiotic stress in cassava.

Abstract:The oriental hybrid lily ‘Sorbonne’ was used to precisely study the effects of high temperature on the flowering quality of lily. The changes in flower diameter， color， and content of cyanidin at different developmental stages of flower buds treated at different temperatures and times during the period of full bloom were investigated. The changes in the expression level of three key genes involved in the synthesis pathway of cyanidin including LhCHS， LhF3H and LhANS during temperature treatment were identified as well. The results showed that the S5 and S6 stages were key period for color development of 'Sorbonne' buds. The flower diameter was significantly smaller， the content of cyaindin was significantly reduced， and the color of tepal was lighter at the stage of full bloom after the buds were treated at a temperature higher than 30 ℃ for 4 days. The results of qRT-PCR analysis showed that high temperature treatment above 30 ℃ during the critical period of flower bud coloration significantly downregulated the expression of anthocyanin synthesis genes such as LhCHS， LhF3H， and LhANS， thereby affecting the synthesis of flower color during the period of full bloom. It will provide a theoretical basis for temperature control in the production and postharvest process of lily‘Sorbonne’.

Abstract:A senescence-related gene LoENDONUCLEASE 1 （SAG10） was cloned from the tepals of Lilium oriental hybrid ‘Siberia’ to study the molecular mechanism underlying the senescence of flower in lily （Lilium spp.）. The expression of SAG10 was analyzed with qRT-PCR， and the function of LoENDONUCLEASE 1 gene was identified with Agrobacterium-mediated stable overexpression system of Arabidopsis thaliana and transient overexpression system of lily tepals. The results showed that the open reading frame （ORF） of LoENDONUCLEASE 1 gene was 921 bp， encoding 306 amino acids. LoENDONUCLEASE 1 was uniquely expressed in the senescence of flowers and leaves in lily， and was induced by abscisic acid and salicylic acid. The content of chlorophyll in leaves of Arabidopsis strain with overexpressing LoENDONUCLEASE 1 was significantly lower than that in the control. LoENDONUCLEASE 1 gene was transiently overexpressed in lily tepals， accelerating the senescence of tepals in lily. The content of malondialdehyde （MDA） and ion leakage rate in the overexpressed tepals were significantly higher than that in the control. It is indicated that LoENDONUCLEASE 1 can promote the senescence of flowers and leaves in lily.

Abstract:The bulbs of Lilium ‘Red Palace’ were used to study the physiological characteristics of lily in response to salt stress and comprehensively evaluate the salt tolerance of lily.Different concentrations of NaCl including 0 mmol/L，50 mmol/L，100 mmol/L，150 mmol/L，and 200 mmol/L were set up.The effects of salt stress on photosynthetic pigments，photosynthetic parameters，osmoregulatory substances and anatomical structure of leaf were analyzed，correlation analysis and principal component analysis on related indexes were conducted.The results showed that the content of chlorophyll a （Chl a） and chlorophyll b （Chl b） in lily leaves decreased significantly with the prolongation of stress time，while the content of free proline （Pro） and soluble protein continued to increase.The content of malondialdehyde （MDA） had a trend of first increasing and then decreasing under the treatment of 50-150 mmol/L NaCl，and an increasing trend under the treatment of 200 mmol/L NaCl.When subjected to stress for 30 days，the net photosynthetic rate （P_n） and transpiration rate （T_r） of the leaves were inhibited，stomatal conductance （G_s） decreased with the increase of NaCl concentration，intercellular CO₂ concentration （C_i） had a trend of first decreasing and then increasing，while water use efficiency （WUE） had a trend of first increasing and then decreasing.The continuous increase in salt concentration inhibited the growth of lily leaves and buds.The anatomical structure indexes of leaves had a decreasing trend in leaf thickness （LT），upper epidermal thickness （UE），lower epidermal thickness （LE），and palisade tissue thickness （PT），except for an increase in sponge tissue thickness.The spongy ratio （SR） increased，while the palisade tissue thickness/spongy tissue thickness ratio （P/S） decreased.The results of principal component analysis showed that there was a significant positive correlation between P_n and T_r，Chl b，LT，and a significant negative correlation with Pro.It is indicated that the concentration of 100 mmol/L is the salt tolerance threshold for lily，and P_n，T_r，G_s，Chl b，LT，and Pro can be used as effective indexes to evaluate the salt tolerance of lily.Lily mainly alleviate salt damage by reducing T_r，G_s，C_i and accumulating osmoregulatory substances under low salt stress.The growth of lily is hindered，and the stress resistance of leaf anatomical structures is weakened under high salt stress.Non-stomatal factors are the main limiting factors for P_n.

Abstract:In order to develop a high-quality formula feed for largemouth bass （Micropterus salmoides）， this study replaced fish meal with soybean meal and added probiotics to investigate the growth and antioxidant tolerance of fish. Juvenile largemouth bass with initial body weight （50.78±1.15） g were used as the research object. The fish meal content of the control group was set to 30%， and on the basis of the control group， the fish meal content of the treatment group was replaced with 25%， 50% and 75% soybean meal， respectively， which were recorded as D25， D50 and D75 treatment groups. In addition， 0.05% Clostridium butyricum was added to 3 treatment groups D25+C， D50+C and D75+C. After 8 weeks of experiment， the growth performance， feed utilization， body composition and antioxidant performance of largemouth bass were analyzed. The results showed that when 25% fish meal was replaced by soybean meal， there were no significant differences in growth performance， body composition and antioxidant capacity of largemouth bass （P>0.05）. But weight gain rate （WGR） and specific growth rate （SGR） decreased significantly （P<0.05）， and feed conversion ratio （FCR） increased significantly when the replacement level of soybean meal reached 50% （P<0.05）. The oxygen species （ROS）， total antioxidant capacity （T-AOC） and superoxide dismutase （SOD） in liver and serum were also significantly changed （P<0.05）. However， there were no significant differences in WGR， SGR， ROS， T-AOC and SOD between the group supplemented with C. butyricum on the basis of replacing 50% fish meal and the control group. When the replacement level reached 75%， the growth performance and antioxidant performance of fish were improved by adding C. butyricum， but still significantly lower than that of the control group. To sum up， the addition of 0.05% C. butyricum could improve the negative effects of 50% substitution of soybean meal for fish meal on the growth performance and antioxidant capacity of largemouth bass.

Abstract:In this study，to investigate the relationship among the three selenoprotein genes selenow2a，selenop2 and selenot2 in yellow catfish，Pelteobagrus fulvidraco，3′/5′ RACE PCR was used to clone the full length cDNAs of three genes，which were 891，1 998 and 1 432 bp with the ORFs of 288，828 and 600 bp，encoding 95，275 and 219 amino acids，respectively. The cDNA sequence analysis of the three genes by online tool SECISerach3 showed that they all contained the stop codons encoding selenocysteine and the selenocysteine insertion sequence （SECIS） element in the 3′ untranslated region （3′ UTR）. Through amino acid sequence comparison and phylogenetic tree analysis，it was found that the predicted amino acid sequences of selenow2a，selenop2 and selenot2 genes shared 82.24%，66.19%，and 79.45% similarity with those of zebrafish （Danio rerio），respectively，and shared 94.74%，68.50% and 90.95% similarity with those of channel catfish （Ictalurus punetaus），respectively，which was shown to be close to the fork of the tree. Quantitative real-time PCR was used to examine the mRNA expression of three selenoprotein genes in the heart，liver，muscle，brain，intestine，spleen，testis and ovaries of yellow catfish，and the results suggested that the mRNA expression levels were tissue-specific. These results suggested that these three genes share the characteristics of selenoprotein family，but are tissue-specific in expression.

Abstract:To explore the potential role of olfactory receptors β subtype （OR-β） in the evolution of feeding adaptation in fish， we analyzed the OR-β genes from 12 fish species with different feeding habits including Megalobrama amblycephala， Ctenopharyngodon idellus， Cynoglossus semilaevis， Gadus morhua， Gasterosteus aculeatus， Larimichthys crocea， Paralichthys olivaceus， Danio rerio， Oreochromis niloticus， Oryzias latipes， Sinocyclocheilus graham and Xiphophorus maculatus. We also detected the expression patterns of the OR-β in the muscle， olfactory epithelium， olfactory bulb and brain of M. amblycephala. The results of evolutionary analysis showed that the number of OR-β varied greatly among fish species with different feeding habits. Herbivorous M. amblycephala and C. idellus had 20 copies and 14 copies， respectively， while carnivorous and omnivorous fish had an average of 1 and 4 copies， respectively. The results of selection pressure analysis showed that a total of 19 branches undergo positive selection， including 9 OR-β genes and 10 branch sites. Among them， the OR-β-4 and OR-β-14 gene of M. amblycephala （P<0.01） experienced strong positive selection. In addition， the OR-β of several Cyprinidae species， such as M. amblycephala， C. idellus， D. rerio and S. grahami， were clustered into one brand， which was positively selected and included 9 OR-β genes of M. amblycephala. The results of qPCR showed that 10 OR-β genes were highly expressed in the olfactory epithelium of M. amblycephala at 12-months of age and 24-months of age. OR-β-9 and OR-β-10 were also expressed in the olfactory bulb and brain tissue， while other OR-β genes were not expressed. Taken together， these results showed that the OR-β genes of the two herbivorous fish were specifically expanded and highly expressed in the olfactory epithelium， suggesting that OR-β might play potential crucial role in adapting the diets of herbivores.

Abstract:To study the role of outer membrane protein A （OmpA） in the pathogenicity of Elizabethkingia miricola， the ompA gene mutant strain （△ompA） was constructed via homologous recombination using E. miricola FL160902 as the wild type strain. Subsequently， the growth characteristics， biofilm formation， serum survival ability， adhesion ability， bacterial colonization of the wild strain and △ompA， as well as their pathogenicity to frogs were analyzed. The results showed that there was no significant difference in growth characteristics and survive ability in frog serum between △ompA and wild strain. However， compared with the wild strain， the biofilm formation capacity of △ompA increased by 66%， and the adhesion capacity of △ompA to bEnd.3 cells decreased by 61%. The results of animal experiment showed that the average bacterial load of △ompA in the blood， spleen and brain of infected frogs were （3.15×10⁸±0.09×10⁸）， （2.11×10⁸±0.07×10⁸） and （6.61×10⁸±0.16×10⁸） copies/g， respectively， which were significantly lower than that of the wild strain infected frogs （P<0.05）， and the lethality rate of frogs infected with △ompA was 37%， which was significantly lower than that of the wild strain （75%）. The results indicated that ompA deletion did not change the antiserum killing ability of E. miricola， but increased the biofilm forming ability of E. miricola， reduced its adhesion ability and decreased its pathogenicity to frogs.

Abstract:The purpose of this study was to construct a recombinant baculovirus strain expressing soluble Toxoplasma gondii MIC1 protein and identify the biological activity of the recombinant protein. The CDS sequence of mic1 gene was amplified by PCR， ligated into the pFastBac 1 vector， and then transformed into DH10Bac cell. To obtain recombinant baculovirus， recombinant Bacmid was extracted and transfected into Sf9 cells. The transfected Sf9 cells exhibited typical lesion on the 3rd day after transfection. The results of indirect immunofluorescence assay and Western blot showed that the MIC1 recombinant protein was successfully expressed in transfected Sf9 cells. The purified MIC1 recombinant protein not only possessed the ability to bind to sialyllactose， but also could stimulate Balb/c mice to produce a high level of specific antibodies （>1∶25 600）. These results showed that the biologically active MIC1 recombinant protein was successfully obtained through the baculovirus expression system.

Abstract:Ozone is used in the processing of aquatic products to remove the fishy odour and improve the whiteness. In order to investigate the effect of ozone oxidation on processing adaptability of silver carp surimi, the rheological properties of ozone-oxidized silver carp myosin were studied by using rheometer and the fitting of Ostwald-de Waele equation and Burgers equation. Meanwhile, the gelation process and gel properties were also analyzed. The results showed that the storage modulus (G') of the myosin solution was always larger than the loss modulus (G''). At 45 s of ozone oxidation, G' and G'' reached their maximum values, with the weakest frequency dependency. Ozone-oxidation decreased the viscosity coefficient k of myosin solution. The gelation trend of myosin was similar in different ozone oxidation time, but the time required for myosin G' to reach the peak value decreased and the peak value increased due to ozone oxidation. In the creep recovery scanning test, the relaxation time of myosin was reduced and the elastic response was accelerated by ozone oxidation. The shape variable ε was the smallest at 45 s of ozone oxidation. Therefore, myosin solution belongs to weak gel and pseudoplastic fluid, and a certain degree of ozone can accelerate the formation of myosin gel in heat-induced gelation, and the gel properties can be improved to a certain extent.

Abstract:A method for predicting the aroma type of cigarette recipe module based on near-infrared spectral feature dimensionality reduction was proposed to classify and identify the aroma type of cigarette recipe modules with near-infrared spectroscopy. The near-infrared spectral data of 238 cigarette recipe module samples from 2017 to 2019 were selected to construct an aroma prediction model based on feature variables through combining the recursive feature elimination method in feature engineering and three machine learning techniques including BP neural network， random forest and XGBoost. Compared with the classification effect of full spectrum data training， the spectral feature variables filtered by recursive feature elimination method effectively improved the recognition accuracy of aroma type of cigarette recipe module. Among them， the algorithm of XGBoost had the best classification performance， with a model recognition accuracy of 90.41% for the test set. It is indicated that the prediction method of aroma type based on the recursive feature elimination of near-infrared spectral features has a certain role in assisting decision-making in the rapid positioning， scientific evaluation and cigarette formulation design of cigarette recipe modules.

Abstract:Wind tunnel devices play an important role in studying the lodging resistance of rapeseed in strong wind environments. The wind tunnel model of rapeseed lodging resistance test was established based on computational fluid dynamics software Fluent. The design of parameter and simulation tests on key parts of the wind tunnel including diffusion section, stabilization section and contraction section were conducted. The effects of key parts of the wind tunnel on the quality of the wind tunnel flow field were analyzed. The optimal design scheme was selected with orthogonal experiments. The results showed that the variation coefficient of wind velocity at the outlet of the wind tunnel increased when the length of the shrinkage section Ls increased, and the quality of airflow decreased in the single factor experiment. As the length of the stable section Lw increased, the coefficient of variation of wind tunnel outlet wind speed first decreased and then increased. When Lw was 1 000 mm, the coefficient of wind speed variation was the lowest and the airflow quality was the best. The wind speed variation coefficient of wind tunnel outlet first decreased and then increased with the increase of the outlet length of the stabilization section of the damping net distance. When the damping net was 0.65Lw away from the wind tunnel outlet, the variation coefficient of wind speed was the smallest. Among the 9 orthogonal experimental schemes, when the shrinkage section length was 600 mm, the stabilization section was 800 mm, and the damping net was 0.65Lw away from the wind tunnel outlet, the average variation coefficient of wind speed in the corresponding wind tunnel test area was 0.139. The wind speed was more stable than other schemes, and the airflow quality was the best. It is indicated that there is no significant difference between the measured wind speed and the simulation value in scheme 2 wind tunnel. It will provide data support and proof for the design of wind tunnel.

Abstract:The size difference of the fruit itself results in poor robustness and low accuracy of the model for predicting the content of sugar. Eliminating the influence of fruit size differences is of great significance to improve the accuracy of fruit sorting models. The NIR spectra of apples with different fruit diameters were collected by an online NIR spectroscopy detection device， and the partial least squares （PLS） models of the content of sugar in apple （SSC） were established after various pre-processing of the spectra. The modeling sets in the diameter of apple fruit group with 75-85 mm were used to predict the prediction set samples in the diameter of apple fruit group with 65-75 mm and 85-95 mm， respectively. The modeling and prediction sets in the diameter of apple fruit group with 65-75 mm， 75-85 mm， and 85-95 mm were used as the modeling and prediction sets of the mixed size model for predicting the content of sugar in apple， respectively. The model was simplified by using the feature spectral selection algorithm. The correlation coefficient R_p was increased from 0.805 to 0.943， the root mean square error value RMSEP was reduced from 0.778 to 0.480， and the RPD was increased from 0.96 to 3.05 compared with the optimal set of model for predicting the content of sugar in apple established when the modeling set and the prediction set had different fruit diameters. It is indicated that simplifying the general model established can reduce the effects of apple size on the model for predicting the content of sugar in apple and improve the prediction performance of the model.

Abstract:The body condition score （BCS） of dairy cows is one of the important indicators of animal health and welfare in precision animal husbandry farm，and an important basis for decision-making and management. Traditional methods of assessing body condition are mainly manual assessments. The traditional method is manual evaluation，which relies on human visual or tactile scoring evaluation of specific areas of the cow's body. Although the cost of manual method is low，it is time-consuming and labor-consuming. The manual evaluation has the disadvantages of subjectivity and low repeatability of scoring results. With the development of artificial intelligence，deep learning technology has been widely used in monitoring animal information. However，there is still a need for an efficient and real-time method of monitoring body condition of cow to meet the needs of commercialization. An improved lightweight attention mechanism network model （Shuffle-ECANet） was proposed to solve the problems mentioned above. Firstly，8 972 image samples containing the tail of cows were selected，and the body condition of cows was manually scored by animal husbandry experts to construct a relevant dataset. Then，an efficient channel attention module was introduced into the feature extraction structure of lightweight ShuffleNet-v2 to strengthen the network's ability to extract body condition features of cow. The H-Swish activation function was used to avoid neuronal necrosis. Finally，the Shuffle-ECANet network model was obtained by further simplifying the network structure. Three evaluation indicators including precision，recall，and F₁ were selected to evaluate the performance of models. Four models including EfficientNet-v1，MobileNet-v3，ShuffleNet-v2 1× and ResNet34 were used for comparative analysis to verify the performance of Shuffle-ECANet network model. The results showed that the Shuffle-ECANet model outperformed EfficientNet-v1，MobileNet-v3，ShuffleNet-v2 1× and ResNet34 in the results of evaluating body condition with BCS estimations within 0，0.25 and 0.50 units，respectively. The effectiveness of Shuffle-ECANet method was proved as well. The lightweight Shuffle-ECANet model proposed had an accuracy of more than 97% for each category，indicating that the model can distinguish different body conditions of cows effectively. It will provide the possibility for the refined management of individual body condition of dairy cows in large-scale pastures and a basis for the future application in low-computing power equipment，and a theoretical basis and idea for the commercialization of scoring body condition of cow.

Abstract:16 kinds of wet soil with different particle diameter and moisture were used to study the changes in adhesion characteristics between soil-touching components and soil during soil drying. The slope sliding test of metal plate （65Mn steel） was conducted to measure the relationship between the particle diameter and moisture of soil and the adhesion between metal soil-touching components. The microstructure of soil samples was analyzed with microscope. The adhesion phenomena between soil and metal plates during the drying process was observed. The results showed that the "traces" produced by soil with a moisture of 30% and 40% sliding on the metal surface were more obvious than those by soil with a moisture of 10% and 20%. Among them， the soil with moisture of 30% and the particle diameter of 10-50 μm had the maximum adhesion. The differences in particle diameter， overlooking perimeter， and overlooking area increased with the increase of moisture and particle diameter before and after soil drying. During the drying process， the gap between the particles gradually decreased， some particles had "diffusion"， "contraction" and other phenomena， some particles occurred relative displacement. The soil with moisture of 30% and the particle diameter of 10-50 μm had the maximum relative displacement of 13.78 μm. The soil adhesion first increased and then decreased with the increase of moisture. As the particles decreased， the soil adhesion gradually increased. When the moisture was below 30%， the greater the particle displacement before and after drying， the stronger the soil adhesion. It is indicated that the soil with moisture of 30% and particle diameter of 10-50 μm exhibits the strongest adhesion and the phenomenon of maximum relative displacement of particles during soil drying.