Abstract:The paddy field farming system in Southern China plays an extremely important strategic position and role in the agricultural production of China and the whole farming systems. Over the past 70 years since the founding of new China,the paddy field farming system in Southern China has been continuously adjusted,reformed and developed,and great achievements including increased yield,improved quality,increased models and enhanced functions have been made. At present,the development of paddy field farming system in Southern China is facing many problems and challenges including the reduction of multiple cropping area,abandonment of cultivated land,ecological damage,environmental pollution,soil degradation,decline of biodiversity,frequent natural disasters,reduction of economic benefits,weakening of sustainable development ability,and so on. In view of the problems and challenges mentioned above,we must take positive and effective strategic countermeasures and measures including clarifying a goal and establishing the strategic goal of “Highquality development” of paddy field farming system in Southern China and follow the three principles including the principle of combining resource development,utilization and protection,the principle of unifying development quality,speed and benefits,and the principle of coordinating economic benefits,social benefits and ecological benefits. Specific measures of “One guarantee,to protect cultivated land resources ”,“Two expansion to expand winter planting and rice planting ”,“Three construction to build green ecology,high standard farmland and establish a disaster prevention and reduction system ”,“Four reform to transform single cropping rice to double cropping rice,transform indica rice to japonica rice,transform inferior varieties to highquality varieties,and transform continuous cropping to crop rotation ” and “Five savings to save land,water,fertilizer,medicine and energy ” should be taken. This article has important reference value and positive significance for the reform and development of paddy field farming system in Southern China at present and in the future.

Abstract:At present,the development of rice industry in China faces prominent problems including the difficulty of stabilizing the planting area,the difficulty of ensuring effective linkage between production and demand,the lack of breakthrough varieties,the low efficiency of rice planting,and the lack of light,simple and high-yield technologies. The development of the rice industry shows the trend of large-scale planting,high-quality varieties,intelligent technologies,personalized consumption and concurrent operation. Based on the situation reviewed above,this article proposes strategies including stabilizing the planting area,improving quality and ensuring supply,optimizing policy system,strengthening scientific and technological support,and making market regulation perfect.

Abstract:How to balance the contradiction between agricultural production and environmental resources is a huge challenge for geneticists and breeders in China and worldwide. In response to this challenge,geneticists and breeders in China proposed the notion of “Green Super Rice” (GSR),established a whole-genome selection and gene-specific selection system,discovered a batch of green trait genes for high yield,superior quality,resistance to pests and diseases,tolerance to abiotic stresses,and high nutrient-use efficiency. The breeding and application of a large number of Green Super Rice varieties has promoted the paradigm shift of the goals and models of crop genetic improvement. This article summarized the concept,development and achievements of Green Super Rice. The breeding and application of green,nutritious and high-quality rice were prospected to enhance the development of green agriculture.

Abstract:Rice is the most successful crop in the utilization of heterosis in China,and it has made a huge contribution to the increase of food production in world. Asian cultivated rice (Oryza sativa L.) includes two subspecies of indica/xian and japonica/geng. The distant heterosis between indica/xian and japonica/geng subspecies is particularly prominent,which can be used as an important way to increase the yield of rice per area. However,the hybrid fertility between xian and geng subspecies is generally low,which is the biggest limiting factor in the utilization of distant heterosis. This article analyzed the genetic basis of rice xian-geng hybrid sterility,and revealed the molecular mechanism of corresponding hybrid sterility loci. On this basis,the origin of wide-compatibility genes was studied. This type of genetic resources can be used as a “bridge” for the breeding of intersubspecific hybrid rice,and can be used to improve the fertility of xian-geng hybrid rice. The theoretical results above have promoted the high efficiency and precision of the genetic improvement of the seed setting rate of xian-geng hybrids. The combination of two-line method and three-line method with “xian male sterility line andgengrestorer line ” and “geng male sterility line and xian restorer line” has become an important way for the large-scale utilization of strong intersubspecific heterosis of xian-geng hybrid rice. Developing xian-geng hybrid rice with high-yield,quality,and nutrition that integrates green,nutritious and healthy traits is one of the important directions for breeding rice in the future.

Abstract:Rice is one of the staple food crops in China.High yield with good quality is not only the focus of rice basic studies,but also the main goal of rice breeding.Rice qualities mainly include milling quality,appearance quality,sensory quality,and nutritional quality,which are complex traits affected by both genetic and environmental factors.This article systematically reviews the classification of rice quality traits,influencing factors,the progress of the genetic basis and molecular improvement of rice quality.The prospects of studying rice quality are discussed.Sensory trait controlled by the major gene Wx is a key quality that determines whether rice is delicious or not.Wx,encoding a granular-bound starch synthase,is the major gene that affects the amylose content,gel consistency,RVA and taste of rice.Variation on Wx leads to the difference of amylose content ranging from 0-30%,the different gel consistency and taste score.ALK responsible for gelatinization temperature and fgr for fragrance of rice affect rice sensory quality as well.GS3,GW5 and Chalk5 are the major genes responsible for the diversity of the major components of rice appearance quality including grain length,grain width and grain chalkiness of rice.Molecular marker-assisted selection and genome editing of these important rice quality genes have achieved great progresses.Yet,the genetic basis of rice overall quality is still rarely understood.The quality of most commercial rice varieties in China is still not good.More studies are still needed to fully uncover the genetic basis of rice quality and to improve the quality of elite rice varieties.It will provide guidance for the genetic improvement of rice quality and the breeding of rice varieties with high-quality.

Abstract:Nitrogen fertilizer application plays an important role in ensuring food security in China,but excessive application of nitrogen fertilizer not only reduces the nitrogen utilization efficiency (NUE),but also results in a series of environmental pollution problems. Synergistic increase of yield and NUE is an important challenge in rice production in China since the 21st century,and it is currently a hot spot in studying the cultivation,physiology and breeding of rice as well. This article introduced the basic principles and fertilization techniques of typical nitrogen fertilizer management strategies at home and abroad. The agronomic traits related to nitrogen efficiency of rice varieties with high NUE,especially the green super rice,were summarized. The physiological and molecular mechanisms of high-efficiency absorption and utilization of nitrogen by rice,especially the effects of nitrogen on leaf structure/photosynthetic physiology and the important genes regulating NUE discovered recently were reviewed.

Abstract:Nitrogen is the basis for the formation of rice yield and quality,and is also the most needed element during the growth process of rice. The large use of nitrogen fertilizer can guarantee rice yield and maintain national food security,but also cause problems such as low utilization rate of resources,rice quality decline and environmental pollution. In this paper,the physiological basis of carbon and nitrogen in rice yield and quality and the response mechanism of nitrogen fertilizer were reviewed,and the methods of quantitative fertilization and formula fertilization were used to improve the nitrogen use efficiency of rice and reduce the environmental pollution on the basis of high yield and good quality,in order to provide reference for the theory of high yield and good quality cultivation of rice.

Abstract:Water-saving and drought-resistant rice(WDR) is a novel type of rice variety that integrates high-yield,high-quality,water-saving and drought-resistance.The development of WDR can not only reduce the dependence of rice production on water resources,expand the scope and area of rice cultivation,and help ensure food security,but also changes the traditional rice planting methods and significantly reduces the labor intensity of rice production and the negative impact on the environment.Therefore,the development of WDR is conducive to the promotion of “two-oriented” agriculture,i.e.,resource-conserving and environment-friendly agriculture.This article discusses the development status,advantages and main problems to be resolved of WDR in China.The main factors that may restrict the development of WDR were analyzed.The research directions of WDR needed to be strengthened in the future were proposed.It will provide a guideline for the future study and development of WDR in China.

Abstract:Under the trend of green and low carbon in current agricultural development,green pest control technologies are very important to ensure food security. Also,the wide application of these green pest control techniques will promote the sustainable development of agriculture. In recent years,great progress has been made in the research and application of green pest control technology. In this paper,the newly progress of research and application of green rice pest control in China were systematically summarized from the perspectives of ecological regulation and management,agronomic cultivation measures,physical control technologies,biological control and emergency precise chemical control. The development of representative techniques,such as ecological engineering technology,the Fan-inhaling Lamp and the unmanned aerial vehicle (UAV) low-volume spraying technology for paddy field,has provided strong support for the development of green rice pest control. In prospect,to carry out regional and characteristic integrated research and promotion of green pest control technology,strengthen policy support and technical training,will further improve their importance in reducing pesticides use and green rice production.

Abstract:Intelligent control is the key core technology for the development of full mechanization of rice production to intelligence. This article summarized and analyzed the use of rice production machinery and mechanized operations at home and abroad from four aspects of rice cultivation,planting,field management and harvesting. It emphasized the application and development of intelligent technology in the full mechanization of rice production. It covered the plow deep intelligent adjustment and automatic flat plug tray technology,rice seedlings precision seeding performance detection and intelligent seeding technology,precise technology,water-saving irrigation technology,the technology of variable rate fertilization,weeding robot technology,plant diseases and insect pests and unmanned aerial vehicle remote sensing monitoring spraying technology,key components harvester monitoring and intelligent control technology,the impurity rate and on-line monitoring technology,automatic navigation and breakage driverless technology. The technical difficulties limiting the development of mechanization to intelligence in the whole process of rice production were pointed out. The development of multi-sensor information fusion is proposed to improve the intelligent perception ability of rice production machinery. The research and development of high-efficiency,precise and energy-saving intelligent equipment for rice must be innovated and accelerated. The high-end navigation system that integrates inertial navigation system and machine vision system must be explored. Promoting the intensive operation of general machinery and the sustainable development of modern agriculture is the key to realizing the mechanization and intelligence of the entire process of rice production.

Abstract:The water-saving and drought-resistant rice variety Hanyou 73 was used to conduct field experiments with sowing dates including T1 (May 30),T2 (June 9th,farmers’ customary practices),T3 (June 19th) and periods of supplementary irrigation including W1 (tillering stage+booting stage),W2 (tillering stage+heading flowering stage,farmers’ customary practices),W3 (tillering stage+milk filling stage) to comprehensively study the effects of sowing dates and periods of supplementary irrigation on the growth and development,yield and quality,and resource utilization efficiency of rice under dry cultivation. The results showed that when the sowing date was advanced,the plant height,number of tillers,yield,and water use efficiency of rice all increased significantly,and its yield reached 11.03 t/hm2 with an increase of 16.72% compared with that of T2. Meanwhile,the chalkiness was significantly reduced,and the economic benefit was increased by 15.81%. When the sowing date was delayed,the yield and total water use efficiency were significantly reduced,and the rice quality did not change significantly. Compared with W2,W1 significantly increased rice yield and water use efficiency,but rice quality did not change significantly. W3 was more significant in the increase of yield,water use efficiency and economic benefits,reaching 11.67 t/hm2,3.33 kg/m3 and 15 028 yuan/hm2,respectively. At the same time,rice quality was significantly improved. Therefore,the sowing date for the rice (drought)-wheat annual rotation system in Hubei Province should be appropriately advanced,and it is recommended to sow before mid-June. In the case of limited irrigation water,priority should be given to irrigation of the W3 period (tillering stage+milk filling stage).

Abstract:Two conventional rice cultivars with good taste quality,indica/xian rice Yangxizao and japonica/geng rice Exiang 2,were used to study the effects of wood vinegar and different nitrogen application on the yield and eating quality of rice. Under the conditions of 4 nitrogen fertilizer application levels (0,50,100,200 kg/hm2),spraying and not spraying wood vinegar were set. The results showed that comparing with non-application of wood vinegar,the wood vinegar application significantly increased yield under different nitrogen application conditions. Spraying wood vinegar significantly increased the yield of conventional japonica geng rice Exiang 2,especially under low nitrogen level. Spraying wood vinegar under different nitrogen application conditions significantly improved the processing quality of rice,and had a significant effect on the rate of brown rice and milled rice. It was also beneficial to improve the cooking and eating quality of rice,which can significantly increase the reduction value of rice,reduce the disintegration value,and then increase the taste value of rice. The effect of vinegar on the eating quality of rice was more obvious when the wood vinegar applied under low nitrogen level.

Abstract:Rice-crayfish integrated system (RC) is a high-efficiency ecological agricultural system which combines the rice planting and crayfish culturing.In order to explore the impact of RC on the microbiome of paddy water,the water microbial diversity and community structure of RC and rice monoculture system (RM) were determined by using 16S rDNA amplicon high-throughput sequencing.The results showed that RC significantly improved the microbial diversity.The microbial community structure of paddy water was significantly different between RC and RM,which could be attributed to water physi-chemical factors,such as total nitrogen and nitrite nitrogen.The relative abundance of Actinobacteria and Cyanobacteria in RC was significantly higher than that in RM,while the relative abundance of Proteobacteria and Bacteroidetes in RC was lower than that in RM.Actinomycetales,Rhizobiales,and Synechococcales are the main biomarkers of water microbiome in RC,while Flavobacteriales,Betaproteobacteriales,and Rhodocyclales are the main biomarkers in RM.Six keystone taxa were identified from the water microbiome in the paddy fields,which mainly belong to Burkholderiaceae,Saprospiraceae and Polyangiaceae.Furthermore,through functional prediction and relative abundance comparison,we found that the metabolic capacity of water microbiome in RC was significantly higher than that in RM,especially the relative abundance of energy metabolism pathway was significantly higher than that in RM.In conclusion,RC formed a better water microbiome with high diversity,stable structure,and strong function and improved the material circulation and energy utilization rate of paddy ecosystem.Those results provide a basis for the utilization of microbial resource in rice-crayfish integrated system.

Abstract:In order to explore the physiological mechanism and metabolic differences of the green spots ("GrS") formed during the natural air-curing process of cigar tobacco,to improve the appearance quality of wrapper tobacco leaves,and to improve the air-curing technology,the cigar tobacco‘Chuxue 10’was used as an experiment materials,using high-pressure liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) non-targeted metabolomics technology to analyze the metabolic differences between the GrS and normal tissues of tobacco leaves. The results of the study showed that the contents of chlorophyll and chlorogenic acid in GrS were significantly higher than those in normal parts,and a large amount of undecomposed chlorophyll and chlorogenic acid deposited at the end of the drying period was the physiological basis for the formation of GrS. There were significant differences in tyrosine metabolism,phenylalanine metabolism and flavonoid biosynthesis between GrS and normal tissues. Chlorogenic acid and dihydrozeatin can be used as chemical markers in the formation process of GrS,and their content can be detected to monitor whether there will be GrS in the process of air drying. During the yellowing period of tobacco leaves,the humidity in the drying room drops suddenly and the extreme difference is too large,which may be the external environmental factor for the formation of GrS. It is recommended to use the humidity controlled drying room and appropriately increase the humidity in the yellowing period.

Abstract:A method of accurately evaluating the spatial equity of urban park green space oriented by the theory of green space equity and helped with geographic information system (GIS) was proposed by optimizing the accessibility evaluation model starting from service capability of urban park green space and human demands and using indicators including effective green space service capacity,multi- threshold green space service coverage,accessibility,and location entropy of green space service per capita to improve the use efficiency of the urban park green spaces and find shortcomings in the distribution/layout of park green spaces. A case study of Haidian District in Beijing was conducted as an empirical study for spatial equity of urban park green space in Haidian District. The results showed that the supply of large-scale urban parks in Haidian District was sufficient. The supply of community -based recreational green space in Haidian District needs to be improved. Royal Mountains and Gardens of Beijing Western Suburbs construction greatly improved the accessibility of community green space. Based on the results,it is recommended to increase the green area of community-level urban parks and increase the convenience of community access to green space. It is indicated that the method of accurately evaluating the spatial equity of urban park green space proposed can provide a basis for the renewal and planning decisions of urban park green space.

Abstract:Protein requirements are different at different growth stage. Generally,crayfish in the early stage of life usually have a high protein requirements. An 8-week experiment was performed to investigate the effects of different dietary protein levels on growth performance,body composition and antioxidant capacity of Procambarus clarkii at three different growth stages. The results showed that with the increase of dietary protein level,WGR and SGR of crayfish increased first and then stabilized in three different growth stages. With the increase of dietary protein level,the FCR decreased first and then stabilized. In the first and second growth stage,the crude protein increased first and then stabilized; in the third growth stage,the lowest crude protein content was observed in the group fed with 250 g/kg dietary protein. With the increase of dietary protein level,both the superoxidase dismutase (SOD) activity and the phenoloxidase (PO) activity increased in the first and second growth stage; in the third growth stage,after the dietary protein levels exceeded 300 g/kg,both the SOD activity and the PO activity decreased. Based on these findings and a broken-line model of specific growth rate,the optimal diet protein levels for the crayfish with initial body weight of 0.026±0.001 g,1.04±0.03 g and 5.06±0.17 g,were 403.3 g/kg,358.8 g/kg and 305.6 g/kg,respectively.

Abstract:Estrogen is an essential steroid hormone that promotes fish gonad development and maintains reproductive function,contributing to regulate energy metabolism and growth development. Estrogen receptors (ERs) are the key receptor that mediate estrogen regulation in multiple tissues and organs. Therefore,ERs may be related to fish growth and gonadal development. In this study,we cloned the coding sequences (CDS) of estrogen receptor genes in blunt snout bream (Megalobrama amblycephala),including ERα (1 904 bp),ERβ1 (1 842 bp) and ERβ2 (2 609 bp). Through comparing the homology of ERs among different species,we found that the ERs of M. amblycephala share high similarity with carp,goldfish and zebrafish. To analyze the relationship between ERs and gonad and growth,we collected one-year,two-year,and three-year old M. amblycephala,and selected individuals with fast growth (FG) and slow growth (SG) at each age stage. The expression of ERs in the gonad and muscles of M. amblycephala at different ages was analyzed. The results showed that in the early stage of gonadal development,ERa tended to play an important role in growth rather than gonad development. At the metaphase of gonadal development,ERα had an effect on gonad development,and ERβ1 replaced the effect of ERa in growth. After gonadal maturation,the expression of ERα and ERβ1 in the FG group was significantly higher than the SG group,but the expression difference of ERβ1 between FG and SG groups was only shown in males,while ERα affected both males and females. In addition,the expression difference of ERβ2 between FG and SG groups was contrary to that of ERα and ERβ1,which inhibit growth in the early and middle stages of gonadal development. Taken together,ERs could promote the gonads and growth of fish to a certain extent. Meantime,ERα,ERβ1 and ERβ2 might form a complex regulatory system to influence with each other and jointly regulate body growth and gonadal development.

Abstract:To identify molecular makers related to the disease-resistance traits after the porcine reproductive and respiratory syndrome virus (PRRSV) infection,a total of 159 healthy piglets from Large White × Tongcheng advanced generation intercross population were infected with PRRSV and genotyped with the “Zhongxin No.1” SNP chip.The lymphocyte percentages at different days post-infection (dpi) were measured as disease resistance indicator.The results showed that single nucleotide polymorphisms (SNPs) rs81257542,rs334594334 and rs329240026 in DDX17 and BTG1 genes were significantly associated with lymphocyte percentages (P<0.05) at different time points post PRRSV infection.Allele C in rs81257542,allele A in rs334594334,and the combined genotype CC-AA were the dominant allele and dominant genotype,the more the dominant allele,the higher lymphocyte percentage and stronger disease resistance.One-step Tetra-primer ARMS-PCR method was further developed to rapidly genotype rs81257542 and rs334594334.In conclusion,the SNPs of rs81257542 and rs334594334 are potential molecular markers for the percentage of blood lymphocyte associated with PRRS resistance,and the detection method can achieve rapid screening of dominant genotypes.

Abstract:Nocardia seriolae is a pathogen that seriously harms Micropterus salmoides. To understand the drug resistance and the prevalence of drug resistance genes in N. seriolae in the main breeding area for Micropterus salmoides of Sichuan,20 strains of N. seriolae were isolated and identified from Sichuan from 2018 to 2019. Micro broth dilution method was used to determine the drug-resistant phenotype of the isolated strains. It was found that the sensitivity ratesof N. seriolae to doxycycline,tilmicosin,gentamicin,etc. were 100%,the drug resistance rates to penicillin,ceftiofur,cefoxitin,etc. were 100%,and the resistance rates to enrofloxacin and florfenicol were 45% and 20%,respectively. Ten strains showed multi-drug resistance,and the drug-resistant phenotypes of the isolates are different. The distribution of 78 drug resistance genes in 6 classes was detected by the ultra-high-throughput fluorescence quantitative PCR method. The results showed that all 6 classes of resistant genes could be detected in 20 isolates,the detection rate of tetA,tetG,tetS, aacC,acrA,acrB,floR and blaTEM reached 100%,and the detection rate of other resistance genes ranged from 5% to 95%,with regional and bacterial differences,indicating that the SichuanN. seriolae has the potential to evolve into multiple drug resistance.

Abstract:In order to explore the immune-regulation function of 6-shogaol in fish,the growth rate,the production of intracellular reactive oxygen (ROS) and lipid peroxidation (MDA),the antioxidant enzyme activity,and the expression of key genes in the inflammatory and antioxidant pathways were detected in zebrafish liver cells incubated with different concentrations of 6-shogaol for 48 h.The results showed that high concentrations of 6-shogaol inhibited the proliferation of liver cells (P<0.05).The antioxidant effect of 6-shogaol was significant,with the highest activity of antioxidant enzyme SOD and GSH-PX,and lowest production of ROS and MDA in the 20 μmol/L treatment group (P<0.05).The gene expression analysis showed that the mechanism of action might be due to the activation of Keap1-Nrf2/HO-1-antioxidant enzyme signaling pathway by inhibiting the keap1 expression.6-shogaol increased the expression of inflammatory cytokine genes in the NF-κB inflammatory pathway (tnf-α,il-1β,il-6) in zebrafish liver cells (P<0.05).While in contrast to the control group,6-Shogaol down-regulated the expression of anti-inflammatory cytokineil-10.The above results showed that 20 μmol/L 6-shogaol can promote the antioxidant function and 6-shogaol can activate the anti-inflammatory pathways of zebrafish liver cells to initiate immune response.

Abstract:To investigate the mechanism of Bacillus amyloliquefaciens BLCC1-0238 in alleviating non-alcoholic fatty liver disease (NAFLD),a mice NAFLD model induced by a high-fat diet was established,and then low and high dose (106 or 108 CFU) B. amyloliquefaciens BLCC1-0238 was used to intervene. The protective effects of B. amyloliquefaciens BLCC1-0238 on the NAFLD mice were evaluated by examining physiochemical indexes in the serum and histopathological changes in the liver. The effects of B. amyloliquefaciens BLCC1-0238 on gut microbiota and hepatic lipid metabolism in the NAFLD mice were analyzed by genomics and transcriptomics,respectively. Quantitative reverse transcription PCR (qRT-PCR) was applied to verify the reliability of transcriptomics results. The results of physiochemical indexes showed that the levels of TC,TG,ALT,and AST were significantly reduced by B. amyloliquefaciens BLCC1-0238 intervention and the liver histopathological changes demonstrated that B. amyloliquefaciens BLCC1-0238 significantly reduced lipid deposition in hepatocytes. The results of genomic analysis showed that B. amyloliquefaciens BLCC1-0238 altered the microbial community structure in the gut,and significantly increased the relative abundance of Bifidobacteria,which produce short chain fatty acids. The liver transcriptomic analysis showed that B. amyloliquefaciens BLCC1-0238 was mainly involved in negative regulation of lipid metabolism pathways,such as fatty acid and cholesterol syntheses. Additionally,qRT-PCR confirmed the reliability of transcriptomic results. Collectively,B. amyloliquefaciensBLCC1-0238 can alleviate mice NAFLD by changing the microbial community structure in the gut and regulating hepatic lipid metabolism.

Abstract:In order to study the effects of yeast extracts on gel qualities and flavor characteristics of fish cakes,seven different types of yeast extracts including FA31,FA37,FIG12,KU012,FIG22,KA66,FG10 and monosodium glutamate were added to determine the whiteness,texture characteristics,gel strength and water-holding capacity of fish cakes.Three types of yeast extracts including KA66,FA31 and KU012 were selected by comprehensive sensory scores.The taste of fish cakes was further evaluated by electronic tongue.The volatile flavor compounds of fish cakes were evaluated by electronic nose and headspace solid phase microextraction combined with gas chromatograph-mass spectrometry (HS-SPME-GC-MS).The results showed that yeast extracts improved the gel quality of fish cakes.The FA37 yeast extract containing 20% glucan significantly improved the whiteness value,gel strength and water-holding capacity of fish cakes.The FA31 yeast extract containing 80% polypeptide significantly improved the whiteness value of fish cakes.After adding yeast extracts (FA31，KU012，KA66),the umami taste and salty taste of the fish cakes was significantly improved,with no obvious differences in sourness and bitter aftertaste among the fish cakes.The results of analyzing volatile flavor compounds showed that the content of 1-octene-3-ol and nonanal,the main off-odors in fish cakes,reduced to varying degrees after adding three yeast extracts.In the fish cakes with KA66 added,hexanol,2,6-diethylpyrazine,2-heptanone,decane and other flavor compounds that contribute to the flavor characteristics of fish cakes were newly identified.It is indicated that adding yeast extracts can improve the gel quality of fish cakes,enrich and enhance the flavor characteristics of fish cakes.

Abstract:Bergamot essential oil (BEO) is a very common citrus essential oil,which is widely used in the cosmetics and food industries. At the same time,it has a good effect on improving the mood of mice and anti-inflammatory and analgesic as well. This article evaluated the neuroprotective effects of inhaling BEO for various times on micewith Alzheimer’s disease induced by D-galactose (D-gal) and aluminum trichloride (AlCl3). Healthy male Kunming mice received D-gal (120 mg/kg,intraperitoneal injection) and AlCl3 (10 mg/kg,intraperitoneal injection) for 49 days were used to establish an Alzheimer’s disease model. On the 29th day,the positive group received donepezil hydrochloride (oral),the sniffing group inhaled BEO for 1 h or 2 h for 21 d. After treatment,the cognitive behavior of the mice was evaluated by Y-maze and open field test (OFT),and the changes in brain biochemistry were detected by enzyme-linked immunosorbent assay (ELISA). The results of behavioral studies showed that D-gal and AlCl3 significantly reduced spontaneous alternation and motor activities,indicating that the cognitive ability of mice was impaired. The results of biochemical studies showed that D-gal and AlCl3 significantly increased the degree of oxidation stress,the number of inflammatory factors and the content of acetylcholinesterase (AchE). However,the cognitive behavioral impairment and the changes of biochemical indexes of the mice in the 2 h sniffing group were significantly improved. It is indicated that inhalation of BEO for 21 d,especially in the 2 h sniffing group,can significantly reduce the behavioral disorders and biochemical damage caused by D-gal and AlCl3.

Abstract:Near infrared spectroscopy (NIRS) combined with a variety of algorithms was used to conduct rapid and non-destructive quality evaluation of Yuan’an yellow tea.The near-infrared spectra of 90 samples of Yuan’an yellow tea were obtained by scanning,and 11 different methods were used to preprocess the spectra to remove part of the noise information.Then the backward interval partial least squares (BiPLS) method was used to screen the characteristic spectral interval reflecting the quality of the sample and the genetic algorithm (GA) was used to accurately extract the characteristic spectral wavelength.Five NIRS prediction models of yellow tea quality were established.Finally,an attempt was made to analyze information of the spectral functional group.The results showed that the best spectral pretreatment method was multiple scattering correction.The characteristic spectral interval screened with BiPLS method was 9 003.2-7 497.9 cm-1,6 101.7-5 449.8 cm-1 and 4 601.3-4 246.5 cm-1,respectively.GA algorithm accurately screened 75 characteristic spectral data points.The Bi-GA-PLS model had the best robustness and predicted the quality of unknown samples (R2=0.951,RMSEP=1.57,RPD=5.27),which was preliminarily realized to quickly and accurately forecast the quality of Yuan’an yellow tea.By analyzing the spectral information,45 spectral data points mainly reflected the information of functional group including —CHx,C=O and —NHx,representing the monosaccharide,caffeine,theanine and free protein closely related to the quality of the samples.The other 30 spectral data points mainly reflected the information of the functional group including O—H,amide bond and C—H and C—C stretching,representing lignin,starch and cellulose.

Abstract:Aiming at the trend of continuous expansion of fruit and tea gardens,the gradual development of intelligent agricultural mechanization and the lack of fruit and tea garden road scenes in common road semantic segmentation data sets,the semantic segmentation technology was used to some fruit and tea garden roads in Meizhou City,Guangdong Province to realize pixel-level segmentation of roads in fruit and tea gardens. Roads,people,and cars were used as classification objects to establish a scene image data set including 6 032 images of fruit and tea garden road. The data set was randomly divided into a training set including 5 429 images and a test set including 603 images according to a 9∶1 ratio. The MS-PSPNet semantic segmentation model was established based on the PSPNet (pyramid scene parsing network) segmentation model for optimization.The results of training showed that MS-PSPNet model mean intersection over union (mean intersection over union,MIoU) was 83.41%. The number of frames per second (frames per second,FPS) was 22.31. The MS-PSPNet model was applied to fruit and tea gardens under different road conditions and light intensity to conduct field tests and evaluate the accuracy. The results showed that the category pixel accuracy (mean pixel accuracy,MPA) of MS-PSPNet model exceeded 92%. MioU exceeded 91% in all cases of non-hardened road conditions. It is indicated that the MS-PSPNet model has good validity and applicability in road recognition of fruit and tea gardens.

Abstract:The laser induced breakdown spectroscopy (LIBS) combined with chemometrics was used to qualitatively detect Huanglongbing in citrus leaves. The results showed that the LIBS signal intensities of elements P(Ⅱ),Mn(Ⅰ),Si(Ⅰ) and Fe(Ⅰ) in citrus leaves were directly related to the healthiness of citrus leaves,where the intensity of the characteristic peaks of P(Ⅱ),Mn(Ⅰ),Si(Ⅰ) and Fe(Ⅰ) in healthy,moderately and severely infected citrus leaves had a decreasing trend. Five characteristic spectrum were analyzed and fused together by spectral fusion to establish a partial least squares discriminant analysis (partial least square,PLS) model,in which the root mean square error (RMSEC) of the modeling set for Fe(Ⅰ) was 0.394,the correlation coefficient (Rc) of the modeling set was 0.871,and the total false positive rate was 23.1%. The prediction set mean square error (RMSEP) was 0.454,and the prediction set correlation coefficient (Rp) was 0.841,with an overall misspecification rate of 26.6%.The RMSEC for spectral fusion was 0.341 and Rc was 0.905,with an overall false positive rate of 15.5%,and the RMSEP was 0.395 and Rp was 0.867,with an overall false positive rate of 22.7%. Meanwhile,four pre-processing methods including normalization,multiplicative scatter correction (MSC),standard normal variate (SNV) and orthogonal signal correction (OSC) were used to reduce the effects of noise and errors on the spectra,and to establish the PLS model. Results of the LIBS technique combined with orthogonal signal correction (OSC) spectral pre-processing and partial least squares (PLS) modeling methods showed that the RMSEC was 0.027 and Rc was 0.994 〖JP2〗with a total false positive rate of 0. The RMSEP was 0.023 and Rp was 0.995 with a total false positive rate of 0. The three categories of citrus leaves were better classified. It is indicated that the feasibility of using LIBS technology to detect nutrients in citrus leaves. It will provide a method for rapidly detecting Huanglongbing in citrus leaf.

Abstract:Nano-selenium (selenium nanoparticles,SeNPs) has been widely used in agriculture,medicine,biology and other fields due to its characteristics of easy absorption,low toxicity,and high biological activity,etc..However,SeNPs are unstable,easy to aggregate,and difficult to recycle.To overcome these shortcomings,researchers have been devoted to exploring the new methods of preparation and regulation of nano-selenium materials.This article mainly summarizes the methods of regulating the activity of nano-selenium materials and introduces their applications in the fields of biosensing,imaging,anti-bacteria,anti-virus,cancer therapy,and anti-oxidation.Furthermore,the current challenges and future perspectives are proposed.It will provide references for understanding the properties of nano-selenium and developing functionalized nano-selenium food.

Abstract:Fruit juices authenticity technology is becoming a study hotspot in the field of global food nutrition and safety,and its development is very important to control the quality and safety of fruit juice.Combining machine learning with web crawler algorithm retrieval technology,this article reviews the progress and application of fruit juices authenticity technology.It emphasized the progress of fruit juices authenticity technology based on the non-targeted/targeted metabolomics.Combining the development trend of multidisciplinary and computer technology,the trend of coupling development of detection methods,development of supervised machine learning statistical tools,and unsupervised authenticity was predicted.It will provide a reference for further in-depth study in the field of fruit juice authentication.