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[Objective] The paper provides references for the prevention of heavy metal pollution and the protection of cultivated soil environ- ment through exploring the content characteristics and the risk of heavy metals elements of paddy soil in Chongqing. 【Method】230 paddy soil samples were collected from 7 major and typical rice-growing regions in Chongqing, and the pH and the content of 5 heavy metal elements in- cluding Cd, Hg, As, Pb and Cr in paddy soil samples were analyzed. The Nemero pollution index evaluation method and the land accumula- tion index evaluation method were used to analyze the degree of pollution, and compared with the background value of heavy metals in Chongqing soil and the risk screening value of agricultural land soil. The characteristics of heavy metal pollution in Chongqing paddy soil were analyzed and evaluated. Then, the possible sources of heavy metal pollution in soil were explored through Pearson correlation analysis and cluster analysis. 【Result】 The average contents of Pb, Cd, Cr, As and Hg in the paddy soil of the research area were 25.4, 0.312, 66. 8, 4.71 and 0.0827 mg/kg, respectively. Through the analysis of single factor pollution index and Nemero pollution index evaluation methods, 19.57% of the paddy soil sites in the study area were in the state of Cd light pollution, 0.43% was in the state of Hg medium pol- lution, and the remaining points were in the state of no pollution. According to Geo-accumulation index, the paddy soil was lightly polluted by Cd, while the remaining heavy metal elements were at a non-polluted level. However, there were very few soils with extremely high ground accumulation index of Hg (4.03, belonging to the level of strong to extremely strong pollution). It was found that the content of Cd and Hg elements exceeded the background value of Chongqing soil, 2. 84 times and 1.38 times of the background value, respectively, with a cumulative effect; The content of Pb, Cr, As elements was slightly lower than the background value of Chongqing soil, and there was basi- cally no enrichment. The average content of heavy metals in the surveyed paddy soil was lower than the corresponding agricultural land soil risk screening value. Correlation and cluster analysis showed that heavy metal pollution mainly originated from soil formation processes and human factors. [Conclusion] The paddy soil in Chongqing is generally in a clean state, but there is a risk of Cd and Hg contamination. [ABSTRACT FROM AUTHOR]

[Objective] The study aimed to identify the characteristics of heavy metal pollution in the dam soil in the loess ruins and gully are- as and conduct ecological health risk assessment. 【Method] In the paper, the loess remnant gully area was selected as the research object in the Xi' aogou check dam in Xiangning county, Shanxi province. 70 soil samples of 0 -20 cm were collected in August, 2021. The content of Cd, Cu, Pb and Zn, Ni, As, Hg, Cr were determined. ArcGIS 10. 4 was used to interpolate the distribution of soil heavy metals in space, and the single factor index (P;), Nemerow comprehensive index (P), and potential ecological risk index (RI) were used to eval- uate the distribution of eight soil heavy metal elements and the risk level. The PMF model was used to analyze the source of heavy metals of the soil. 【Result】 (i) The contents of eight soil heavy metals in the soil surface of the study area did not exceed the soil pollution risk control standards in agricultural land, but the average content values of Cd, Pb, Zn, As, and Hg were higher than the soil background values in Shanxi province, while the mean values of Cd, Pb, Zn, and Hg were higher than the soil background values. Cd, Cu, Pb, As, and Hg were relatively higher near villages and traffic roads when compared with the other sampling point. They showed a band-like distribution with higher content in the north and south and lower in the middle. (ii) The single factor index method showed that Cd and Hg were the most pol- luted when compared with the other heavy metals. The Nemerow comprehensive index method indicated that the Xi'aogou check dam was slightly polluted. (iii) The potential ecological risk index of a single index showed that Cd and Hg belonged to medium risk, while the others were low risk, which indicated that Hg and Cd had the highest ecological risk in Xi'aogou check dam soil. (iv) The PMF model indicated that there were 5 pollution sources in the Xi'aogou dam land soil, namely agricultural sources, livestock and poultry breeding sources, traffic sources, atmospheric deposition sources, and natural sources with the contribution rate of 22.71%, 24. 22%, 19. 10%, 16.63%, and 18.32%, respectively. And agricultural sources and livestock and poultry breeding sources contributed the most. 【Conclusion] Human activ- ities have already affected the content of heavy metals in dam soil to a certain extent. More attentions should be paid to the potential soil heavy metal pollution caused by Cd and Hg in the future. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to screen leguminous plants suitable for improving the soil of bauxite mine reclaimed soil and provide a reference basis for sustainable agricultural development in mining areas. [Method] Seven legumes, including Sesbania cannabina, Vicia sativa, Astragalus sinicus, V. villosa, Medicago sativa, Stylosanthes guianensis and Coronilla varia, were planted in the reclaimed soil of the Pingguo bauxite mine in Guangxi, and the biomass, presence of root nodules, nutrient content, nitrogen fixation efficiency, biological nitro- gen fixation, soil nutrients, calcium and magnesium ion content, total aluminum and active aluminum content of each legume were determined. The legumes suitable for planting in bauxite mine reclamation soil were screened through principal component analysis, and a partial least squares path model (PLS-PM) was established to explore the factors that affected the biological nitrogen fixation of legumes in bauxite mine reclamation soil. [Result] Among the seven legumes, A. sinicus had the highest below-ground biomass(1.961 g/pot) and above-ground bio-mass (0.344 g/pot), C. varia had the lowest below-ground biomass (0.387 g/pot) and above-ground biomass (0.099 g/pot) while Sesbania had the highest N(7.98% ), P(2.999 g/kg), and K(19.828 g/kg) contents. In terms of nodulation, only Sesbania, A. sinicus, and C. varia had root nodules, while the rest of the legumes did not nodulate. Among the three nodulated legumes, S. cannabina had the highest nitrogen fixation efficiency (80.01%) and biological nitrogen fixation (0.077 g/pot). Principal component analysis of three leguminous plants based on evaluation factors including plant nutrient content, biomass, biological nitrogen fixation, and nitrogen fixation efficiency as evaluation factors showed that comprehensive score of S. cannabina repens was the highest (2.30 points). PLS-PM pathway analysis showed that the biological nitrogen fixation of legumes in bauxite mine reclamation soil was directly influenced by plant nutrient content and soil active aluminum and pH, soil nutrients, and types of plants indirectly influenced the biological nitrogen fixation of legumes by affecting plant nutrient content and soil active aluminum. [Conclusion] S. cannabina, A. sinicus, and C. varia are capable of nodulating and improving the pH, available K, ac- tive aluminum, organic matter content, and biological nitrogen fixation of the reclaimed soil in bauxite mines. Based on the comprehensive e- valuation, S. cannabina is considered as the most suitable legume plant for planting in the reclaimed soil of bauxite mines and can be promo- ted and applied as a legume plant for nitrogen fixation and soil improvement in bauxite mining areas. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the pigmenting regularity of yellow flower petals, and provide a theoretical basis for the research on the color rendering mechanism of yellow flower ornamental plants by analyzing the anatomical structure, chromoplast distribu- tion and pigment content of petals of 8 yellow flower plants species. [Method] The epidermal cells, palisade tissue and pigment distribution of the petals of 8 species of yellow flower plants were observed by light microscope, and the morphological characteristics of epidermal cells and the chromoplast distribution characteristics were analyzed. The contents of flavonoid pigments and carotenoids in the petals were determined by spectrophotometer, and the main colored pigments were analyzed to explore the color mechanism of yellow flower petals. [Result] Among the 8 species of yellow flower plants petal cells, chromoplast was observed in the other six species except for Hibiscus tiliaceus and Hemerocal- lis citrina. The flower pigments and chromoplast were mainly distributed in the upper and lower epidermis and palisade tissue, and most of the chromoplasts were spherical and crystalline. The shape of petal epidermal cells was irregular and polygonal (including long polygon), and the anticlinal wall pattern had shallow waveform, deep waveform, straight or arcuate. Most of the upper epidermal cells showed irregular bulges, while the lower epidermal cells showed small bulges. The carotenoids contents were high in Camellia nitidissima, Cassia surattensis, Thevetia peruviana, Wedelia chinensis and Allemanda neriifolia, however, the carotenoids contents were low in H. tiliaceus, H. citrina and C. indica var. flava. The carotenoid content in T. peruviana was the highest and was significantly higher than H. tiliaceus, H. citrina and C. indica var. flava (P<0.05, the same as below), the carotenoid content in H. tiliaceus was the lowest and was significantly lower than T. peruviana, C. nitidissima, C. surattensis, W. chinensis and A. neriifolia. The flavonoid were higher in A. neriifolia and was significantly higher than H. citrina, A. neriifolia, T. peruviana, C indica var. flava and H. tiliaceus. The flavonoids in A. neriifolia and H. citrina were lower, and were significantly lower than C. nitidissima, C. surattensis, T. peruviana, W. chinensis and H. tiliaceus. [Conclusion] The type of pigment, chro- moplast distribution and petal epidermal cell all affected formation and appearance of color. Among them, when the carotenoid and flavonoid were higher, the more concentrated distribution of chromoplast in the petal epidermal cells was, and the petal colors were darker and the color effect was more obvious. Therefore, it was necessary to focus on type of pigment, chromoplast distribution and characteristics of epidermal cells in study of color rendering mechanism of yellow flower. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to clarify the effects of the interaction of paclobutrazol (PP333) with salicylic acid (SA), jas- monic acid(JA), chitosan (CTS) and benzothiadiazole (BTH) on the growth and disease resistance of banana seedlings, and provide refer- ence basis for the use of inducers to control Fusarium wilt of banana. [ Method] The tissue cultured cup seedlings of banana cultivar * Baodao banana' were used as experimental materials, and PP333 (treatment A) and four commonly used elicitors (treatment B, C, D and E) and double agent treatments (treatment A+B,A+C, A+D and A+ E) were sprayed on the leaves. The growth status, resistance to Fusarium wilt and defense enzyme activities of banana seedlings of each treatment were compared and analyzed by spraying water as the control (CK), combined with the inoculation method of root wounding. [Result 】30 days after treatment, the plant height of banana seedlings treated with va- rious drugs was significantly lower than CK (P<0.05, the same as below), and the stem diameter was generally higher than CK. Among them, the plant height of PP333 combined with BTH was the lowest in the double agent treatment, which was significantly reduced by 31. 84% compared with CK. The stem diameter of PP333 combined with JA was 20. 55% significantly higher than CK. The aboveground dry matter quality of banana seedlings treated with double agents was significantly lower than that of CK, with a decrease of 2.46% -5.74%, and the root dry matter quality was significantly increased by 39.02% -43.90% compared with CK. The disease index of banana F. wilt inthe seedling stage was significantly lower than that of CK, among which PP333 combined with BTH and CTS had a better effect on inducing resistance to banana F. wilt, reaching 57.63% and 50. 85% respectively. The effect of two treatments on the activity of resistance-related enzymes in banana seedlings was obvious. Among them, the activity of phenylalanine ammonia-lyase (PAL) of PP333 combined with BTH and CTS increased by 54.59% -101.69% and 42.09% -103. 50% respectively compared with CK, the activity of polyphenol oxidase (PPO) increased by 77.29% -228.77% and 66.07% -267.65% respectively, and the activity of peroxidase (POD) increased by 121. 82% -204. 16% and 54.31% -117.55% respectively. The activity of superoxide dismutase (SOD) increased by 107.45% -263.51% and 110.00%-301. 07% respectively, and CAT activity increased by 141. 95% -442. 16% and 192. 68% -304. 70% respectively. [Conclusion] The interaction of PP333 and the inducer can increase the activity of defense enzymes in banana seedlings, which has a good effect on strengthening seedlings and inducing disease resistance to banana F. wilt. In general, PP333 combined with BTH and CTS has the best induction effect, and has a prospect of production and application. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to master the soil fertility level and distribution characteristics of soil nutrients in plateau summer vegetables planting base. [Method] The study took plateau summer vegetables planting area in Yuzhong county, Gansu province as the research objects, and measured the soil nutrients in plateau summer vegetables planting base in Gansu province by using soil nutrient quick measuring instrument and agricultural environment measuring instrument. Combined with geostatistics, GIS technology and Kriging in- terpolation analysis, the soil nutrient quality was analyzed. [Result] The variation coefficients of soil AP and AK were more than 100%, which belonged to intensity variation, while the variation coefficients of AN, TN, TP, TK, EC and OM were between 10% and 100%, which belonged to moderate intensity variation; The optimal semi-variance models of soil nutrients were linear, spherical and Gaussian mod- els, and the nugget effect of TN, AP, TP, AK and OM was more than 75%. The spatial correlation was weak, the TK nugget effect was be- tween 25% and 75%, and the spatial correlation of TK system was medium. AN was high in the middle and low in all directions, TP was high in all directions and low in the middle, EC and AK were high in the north and low in the south, TK and OM were high in the south and low in the north, TN and AP were multi-peaked, and the results of Kriging cross-validation were reliable; The soil fertility level of seven veg- etable planting areas in plateau summer vegetables planting base of the plateau was average, with rich contents of TN, AP, TP and OM, me- dium contents of AN and lack of contents of AK and TK. [Conclusion] The soil nutrient content of plateau summer vegetables planting base in Yuzhong county is quite different and unevenly distributed, the soil fertility level is average, and the potassium content is low. Therefore, in the actual production process, we should pay attention to rational fertilization and rotation tillage of different varieties of plateau summer vegetables according to soil fertility level and soil nutrient distribution. [ABSTRACT FROM AUTHOR]

[Objective] The paper aims to explore whether calmodulin-like CMLs participate in the sexual differentiation process in Cucumis sativus L., so as to provide reference for improving the regulatory network of sexual differentiation furtherly. [Method] In the study, CMLS, ACSIG, ACS2 and ACS11 genes of cucumber were cloned, qPCR was used to detect the expressions of CMLS gene in different types of the flowers, and the interactions between CMLS and proteins encoded by major genes of cucumber sex differentiation were detected by the method of yeast two-hybrid. [Result】 CML8 was cloned from cucumber which contained a complete ORF of 441 bp, encoding 146 aa without signal peptide. It was an extracellular protein without transmembrane domain and introns, and contained 4 EF-hand domains with Ca2+ binding ca- pacity, and subcellular was located in cell membrane and cytoplasm. ACSIG, ACS2 and ACSII, three key genes of cucumber sexual differ- entiation were cloned, and sequence alignment showed that the nucleotide sequences and encoded protein sequences of the three genes were consistent with those in the cucumber database. There were significant differences in the expression levels of three genes in the female flow- ers, male flowers and bisexual flowers, and extremely significant differences in male flowers. The yeast two-hybrid experiment showed that CMLS could interact with ACSIG and ACS2, but not with ACS11. [Conclusion] Calmodulin-like 8 (CMLS) was cloned, and CMLS could interact with ACSIG and ACS2, which might participate in the sexual differentiation of cucumber, and the study was the first time to explore the involvement of calmodulin in the process of plant sexual differentiation, and expect to provide reference for calcium signaling system to participate in the process of plant sexual differentiation. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the effects of chilling injury and pre-spraying of uniconazole ($3307) on the phys- iological metabolism of mung bean (Vigna radiata) leaves and yield, studying the effects of low temperature stress at the initial flowering stage on physiological and yield of mung bean, and the alleviating effect of pre-spraying $3307 on stress. [Method] The pot experiment in the research was conducted, and the crop cultivar included Lvfeng 5 (L5) and Lvfeng 2 (L2). S3307 was pre-sprayed and treated with con- tinuous low temperature (average 15 °C) for 5 days and samples were taken every day to analyze the cell membrane permeability, AsA-GSH cycle, content of osmotic adjustment substances in mung bean leaves and yield, and the mitigating effects of $3307. [Result] The content of malondialdehyde (MDA) and the electrolyte leakage in mung bean leaves were significantly increased by chilling damage at the initial flow- ering stage, and the content of ascorbic acid and glutathione, and the content of soluble sugar and soluble protein were significantly in- creased. The 100-seeds weight of L5 was significantly decreased by 2. 17% -16.60%, and the yield per plant was significantly decreased by 10. 37% -44.62%. At the same time, the 100-seeds weight of L2 was significantly decreased by 3. 33% -22. 14%, and the yield per plant was significantly decreased by 12.73% -45.69%. S3307 had the effect of resisting chilling damage at the initial flowering stage. Un- der low temperature conditions, pre-spraying $3307 effectively increased the soluble sugar and soluble content of mung bean leaves, significantly reduced the MDA content and the electrolyte leakage, and significantly increased the content of ascorbic acid and glutathione. Spra- ying $3307 had the regulatory effect of increasing the yield of mung bean. Under normal temperature conditions, L5 and 12 in a single plant significantly increased by 4. 70% and 7. 87%, respectively. Under the conditions of chilling, the 100-seeds weight was significantly in- creased by 1. 23% -3.32%, and the yield per plant was significantly increased by 3. 49% -8. 13% when 15 was treated for 1-5 days.. And 100-seeds weight was significantly increased by 1.72% -5.21%, and the yield per plant was significantly increased by 10.94% - 16.55% when 12 was treated for 1-5 days. [Conclusion] Low temperature at the initial flowering stage affected the physiological functions of mung bean leaves such as cell membrane permeability, AsA-GSH cycle, and osmotic regulation substances; Pre-spraying $3307 could ef- fectively alleviate the effects of chilling injury on mung bean physiology and yield. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to identify CBF family members using whole genome data of Prunus sibirica, and to analyze the characteristics and functions of the conserved domains and their expression patterns after low temperature stress of CBF transcription fac- tors. [Method] By the P. sibirica whole genome database, the CBF genes of P. sibirica were searched using BLASTP and HMM, and their conserved structural domains were verified by CDD and MEME. Bioinformatics tools such as Prot-Param, WOLF PSORT, MAGA X, Phyre2 and PlantCARE were used to analyze protein physicochemical properties, subcellular localization, phylogeny, tertiary structure, chromosom- al localization and cis-elements, respectively. Quantitative real-time PCR (RT-qPCR) was used to analyze the expression pattern of CBF gene after low temperature stress in P. sibirica. [Result] In the study, four PSCBF's were identified, all of which possessed the conserved structural domains PKKPAGR and DSAWR sequences of the AP2 gene family. The PSCBFs contained 206-246 amino acids, with a mean molecular weight of 25. 80 KDa and a mean isoelectric point of 5.92. PSCBF3 and PSCBF4 were similar in gene structure and had closer ge- netic relationship. The subcellular localization of 4 PSCBFs was located in the nucleus. Promoter cis-acting element analysis showed that CBF family members could participate in plant hormone and abiotic stress responses. Four CBF members were all acidic and hydrophilic pro- teins. The expression of PSCBF's was higher mainly in the early stage (15 min) after low temperature stress. [Conclusion] The study shows more complete information on the CBF gene family of P. sibirica, which offers new insights into the complex mechanisms and pathways of PSCBF in response to low-temperature stress at different stages. It lays an important theoretical foundation for further investigations into the biological functions of CBF family members. [ABSTRACT FROM AUTHOR]

【Objective】This paper explored the temporal and spatial expansion characteristics and industrial operation mode of farmers’ cooperatives in different topographical areas of Chongqing, mastered the development law of farmers’ cooperatives in Chongqing and analyzed the differences in the selection of different industrial modes, in order to provide data support for promoting the classified cultivation of cooperatives and the formulation of differentiated support policies.【Method】This paper used 2528 farmers’ cooperatives in Chongqing as a sample, comprehensively used terrain distribution index, standard deviation ellipse and other methods to analyze the temporal and spatial patterns and expansion characteristics of cooperatives of different industrial types in four types of terrain. And combined with the questionnaire survey, combed and refined the cooperative operation mode. 【Result】（i） The development of farmers’ cooperatives in Chongqing showed four growth stages in general, with slow growth from 2002 to 2006, rapid growth from 2007 to 2010, the growth rate slowed down from 2011 to 2014, and the growth rate from 2015 to 2018 has dropped significantly. From the perspective of topographical area, the growth rate of Area Ⅳ is the fastest, followed by Area Ⅱ and Area Ⅰ, and Area Ⅲ had the slowest growth rate.（ii） The growth advantages of cooperatives in different industries vary significantly. The growth advantage zone of livestock and poultry industry was Area Ⅳ. The growth advantage zone of the fruit and vegetable, grain and oil, and comprehensive industries were Area Ⅰ and Area Ⅱ. The growth advantage zone of the flower, tree, tea, and peppercorn industries are Area Ⅱ, the tobacco and Chinese medicinal materials industries are Area Ⅲ and Area Ⅳ.（iii） Except for the grain and oil industry cooperatives in the southeast-northwest direction from 2002 to 2006, the rest of the industrial cooperatives had a southwest-northeast distribution at various stages.（iv） There were six main modes of cooperative industrial operation, the livestock, poultry, fruit and vegetable, flower and tree and grain and oil industries use the ‘company + farmers’ cooperative + base + farmer’ model. The ‘company + farmers’ cooperative + farmer’ model was used by fruits and vegetables, flower and tree, grain and oil industries. The industries that use the ‘farmers’ cooperative + base + farmer’ model include fruit and vegetable, flower and tree industries, and the industries that use the ‘Internet+ farmers’ cooperative + farmer’model include livestock, poultry and other industries. The industries of the ‘farmers’ cooperative + farmer household’ model include fruit and vegetable, grain and oil industries, and livestock industry using the model of ‘company + farmers’ cooperative + base + family farm’. 【Conclusion】The number of farmers’ cooperatives in Chongqing is growing, and the advantageous area of different industries has a difference, and it has evolved in the northeast direction, and the operation mode of each industry is diverse. According to the spatio-temporal expansion characteristics of the cooperative and the local conditions, we should accurately find the mode of industrial operation and promote the steady development of cooperatives. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to provide a theoretical basis for the production and management of high-quality wine grapes in Xinjiang, the present paper studied the effects of different light quality treatments on the photosynthetic characteristics and fruit quality of Merlot grapes and the content of phenolic substances in wine.【Method】Taking the Merlot grape as the research object, from the fruit expansion stage to the maturing stage, 6 different colored（white, purple, blue, green, yellow, red） leaf curtains were used for shading treatment. During the fruit maturity period, the appearance indicators: Cluster weight, cluster firmness, weight of single berry, number of berry, skin-to-fruit ratio, seed and berry weight, and physical and chemical quality indicators, such as fruit soluble solids, titratable acid content, total phenols, total flavonoids, flavonoids, flavanols, proanthocyanidins, tannins and anthocyanins in peel, seed and wine were measured. Light response curve was measured by using Li-6400 XT portable photosynthesis measuring system.【Result】Under the different light quality conditions, the maximum net photosynthetic rate (Pn max) of Merlot grape was CK>blue>white>yellow>purple>red>green, except CK, the Pn max of blue and white treatment was significantly higher than that of other treatments, and the Pn max of green treatment was only 5.46 μmol/（m²·s）, which decreased by 173% compared with CK. The cluster weight under green treatment was the largest, reaching 166.22 g, and the weight of a single berry under purple treatment was the largest, reaching 1.3 g, and the difference was significant with that of CK. Under white and blue treatment, the content of soluble solids in fruit increased slightly to 24% and 25%, respectively. The total phenol content of CK was 17.93 mg/g, and compared with CK, the total phenol content of all treatments decreased to different degrees, and the decrease rates of white and red treatments were the least, 36.64% and 34.52%, respectively. Compared with CK, the contents of total flavonoids and flavonoids in seeds under purple treatment increased by 114.49% and 8.36%, respectively. Compared with CK, the contents of flavanols and proanthocyanidins in seeds under white treatment were increased by 108.53% and 49.18%, respectively, and the difference reached significant level with CK. The contents of total phenols, total flavonoids, flavanols, tannins and anthocyanins in wine increased under white treatment, which were 1391.16, 214.89, 1826.21, 2565.71 and 4.86 mg/L, respectively.【Conclusion】The use of white curtain for light quality control from fruit expansion period to maturity period can improve fruit quality and maintain high photosynthetic capacity of Merlot grapes. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to scientifically quantify the development level of digital countryside, effectively promote the comprehensive and organic integration of modern information technology and rural areas, and help rural revitalization.【Method】Based on the latest research results and practical research, and the panel data of 18 prefectures and cities in Henan Province during 2014-2021, 20 indicators were selected from four dimensions: rural digital information basis, new business forms of rural digital economy, agricultural digital transformation, and digitalized rural life, to construct an evaluation index system for the development level of digital countryside. Methods such as entropy weight method, TOPSIS method, Kernel density estimation, Theil index and Moran’s I were comprehensively used to measure the development level of digital countryside in Henan province, and analyze its regional differences and spatial-temporal evolution.【Result】(i) From the perspective of development level, during the investigation period, the development level of digital countryside in Henan province showed an increasing trend year by year. Although the overall development level was not high, the sustainable development momentum was strong.(ii) From the perspective of regional differences, the overall difference of the development level of Henan digital countryside showed a trend of steady decline. Among them, the regional differences contributed the most to the overall differences, and the differences between Central Plains urban agglomeration and Huang-Huai region were the most obvious. The intra-regional differences showed a decreasing trend of Central Plains urban agglomeration, western Henan southwestern Henan, northern Henan and Huang-Huai region.(iii)From the perspective of spatial-temporal evolution, there was an obvious and stable positive correlation among the four economic zones. The Central Plains urban agglomeration was mostly high agglomeration, while the Huang-Huai area was basically low agglomeration. 【Conclusion】The development of digital countryside in Henan province should be combined with provincial conditions and regional characteristics to lay out comprehensively, promote overally, develop stably, bridge the gap, and improve rapidly. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the diversity of culturable fungi and strains producing extracellular enzymes in the Ili River basin, and to understand the distribution of fungi in the Ili River basin.【Method】The bacterial strains were isolated and purified by dilution coating and plate streak method. The diversity and phylogenetic relationship of cultured fungi were analyzed by ITS region sequence, and the bacterial strains with extracellular enzyme activity were screened by qualitative screening medium.【Result】248 culturable fungi were isolated from the Ili River basin, and there were 116 in water, 132 in sediment, belonging to three phylogenetic groups, Basidiomycota and Mucoromycota, 11 classes, 26 orders, 44 families, 82 genera and 4 potential new strains. The results of the distribution of culturable fungi in the Ili River basin showed that the diversity of culturable fungi isolate from sediments in the four rivers was richer than that in the water body. Shannon index analysis showed that the community diversity of culturable fungi in Kashi River was the highest, which was 3.79, the Kunes River was the least, which was 3.21. The results of extracellular enzyme activity of isolate fungi showed that 100 fungi strains produced two or more kinds of extracellular enzymes(mainly amylase esterase and cellulase), and the proportion of extracellular enzyme activity in the main stream of Ili River was the highest, accounting for 77.59%.【Conclusion】There are abundant diversity of culturable fungi in the Ili River basin, and a large number of fungi species resources worth development and utilization were stored. [ABSTRACT FROM AUTHOR]

【Objective】The paper aimed to effectively solve the problem of pollen pollution and cultivate male sterile Lilium using molecular biology technology. The role of ATPase3 gene, a member of the ATPase family, in the male sterility Lilium was studied, which would provide a theoretical basis for the application of this gene in the pollen-free molecular breeding of Lilium.【Method】Anthers of fertile lines and sterile lines of Liliums were used as experimental materials, and a significantly up-regulated ATPase3 gene was screened from the results of transcriptome sequencing of fertile lines. Relative expression of ATPase3 gene in different parts of Lilium was detected by fluorescence quantitative qRT-PCR during the period of microsporocyte. Full-length cDNA sequence of anther ATPase3 gene of Lilium was amplified by qRT-PCR and Race technology, and the structure and physicochemical properties of Lilium ATPase3 were analyzed by various online bioinformatics software（Prot Param, Prot Scale, NCBI Conserved Domain, SWISS-MODEL）. 【Result】The expression of ATPase3 gene in Lilium was the highest in flower organs, and the expression in anthers of fertile lines was 7 times higher than that of sterile lines. Full-length ORF of Lilium ATPase3 gene was 327 bp, encoding 109 amino acids and containing a typical conserved ATPase3 domain; Relative molecular weight of the protein was 12.14 KD and theoretical isoelectric point was 7.71. It was a hydrophilic protein with transmembrane structure, and the secondary and tertiary structures of the protein were predicted. Bioinformatics analysis showed that the predicted protein had typical characteristics of ATP synthase. Homologous sequence analysis showed that the protein had the closest homology with Arabidopsis thaliana plasma membrane ATPase3 and H[+]ATPase1, H[+]ATPase2, H[+]ATPase3, H[+]ATPase8. This protein was a plasma membrane ion transporter that provided energy in plants. It was speculated that the expression level of this protein was down-regulated in the anthers of Lilium sterile lines, which led to the male sterility of Lilium.【Conclusion】In the study, ATPase3 gene was verified to be related to male sterility in Lilium, and ATPase3 gene was successfully cloned and analyzed by bioinformatics. It provided a theoretical basis for the occurrence of male sterility in Lilium caused by the loss of plasma membrane ion transporter function which was encoded by ATPase3 gene. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to study the spatial distribution characteristics and influencing factors of high-standard farmland in Xinjiang, in order to provide decision-making basis and data support for the construction of high-standard farmland in Xinjiang in the future.【Method】 In the study, GIS spatial analysis technology, nuclear density analysis and geographic detector were used to study the spatial differentiation and influencing factors of high-standard farmland in Xinjiang. 【Results】(i) Through the spatial analysis of nuclear density, it was found that the high-standard farmland in Xinjiang was obviously clustered spatially, and there were two significant high-density agglomeration areas in northern and southern Xinjiang, with Tacheng area and Changji Prefecture as the ‘polar core’ in northern Xinjiang, and Aksu area and Kashgar area as ‘polar core’ in southern Xinjiang.(ii) From the perspective of the distribution of construction potential, counties and cities with high construction potential were mainly distributed in the western prefectures of Xinjiang division, and counties and cities with low construction potential were mainly distributed in the eastern prefectures of Xinjiang zoning. The counties and cities with lower construction potential in southern Xinjiang were the most distributed, and the research units in the higher construction potential area had no obvious concentration in space, and the research units in the high construction potential area were mainly distributed in the Tacheng area and Aksu area in northern Xinjiang and the Aksu region and Kashgar area in southern Xinjiang. The counties with high construction potential were mainly distributed in the left prefecture of Xinjiang division, and the counties with low construction potential were mainly distributed in the right prefecture of Xinjiang division.(iii) At the county scale, policy factors had a greater impact on the scale of high-standard farmland construction, and the core interaction factors of each district were related to policy factors; At the plaque scale, it was significantly affected by socioeconomic factors, and the core interaction factors were all related to socioeconomic factors and traffic location factors. The interaction detection results mainly included two interaction types: Nonlinear enhancement and two-factor enhancement, and each influence factor had obvious interaction enhancement effect on the construction scale of high-standard farmland under different partitions. 【Conclusion】 The spatial accumulation of high-standard farmland in Xinjiang is obvious, and natural environmental factors and policy regulatory factors are the main driving factors affecting the construction scale of high-standard farmland. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to investigate the effects of balanced fertilization on the fertility and microbial community structure of Amaranthus tricolor L. inter-root soil, to provide a reference basis for shaping a fertile A. tricolor inter-root soil microenvironment and constructing a high-yielding and high-quality A. tricolor production technology system.【Method】Based on traditional and high-throughput sequencing techniques, the study analyzed the changes of soil fertility and microbial community structure in the inter-rhizosphere of A. tricolor under the conditions of blank control(CK),potassium deficiency fertilization(NP),nitrogen deficiency fertilization(PK),phosphorus deficiency fertilization(NK) and balanced fertilization[188.0,53.0 and 50.0 kg/hm² of nitrogen, phosphorus and potassium(NPK) fertilization, respectively].【Result】Application of different ratios of N,P and K fertilizers increased β-glucosidase, aminopeptidase and phosphatase activities in A. tricolor inter-root soil; Compared with the NPK treatment, the microbial biomass carbon(C),N and P contents of A. tricolor inter-root soil were generally lower in the non-balanced fertilizer treatment; All fertilizer treatments contributed to increase the bacterial diversity and richness of A. tricolor inter-root soil, but only the balanced fertilizer treatment increased the diversity and richness of fungi in the inter-root soil of A. tricolor. At the level of bacterial phylum classification, abundance percentage of the dominant bacterial phylum Proteobacteria, Acidobacteriota, Patescibacteria, Gemmatimonadota, Bacteroidota and Myxococcota in A. tricolor inter-rhizosphere soil in all fertilizer treatments increased, but that of Actinobacteriota and Chloroflexi decreased. At the taxonomic level of bacterial genera, fertilization not only obviously changed the abundance of bacterial genera at the taxonomic level of A. tricolor roots, but also enriched some specific dominant bacterial genera(unclassified＿o＿ Saccharimonadales,norank＿ f＿LWQ8 and Sphingomonas). At the fungal phylum taxonomic level, Ascomycota, Chytridiomycota, Mortierellomycota and unclassified＿ k＿ Fungi were the dominant fungi common to all fertilizer treatments; At the taxonomic level of fungal genera, Plectosphaerella,unclassified＿ f＿ Chytridiaceae,Gibellulopsis,Phialemonium,Mortierella,unclassified＿ k＿ Fungi and Myrothecium were the dominant fungal genera in the top 10 in terms of abundance in the different fertilizer treatments and missing from CK.【Conclusion】The application of different ratios of N,P and K fertilizers helped to improve the fertility of A. tricolor inter-roots soil and create a healthy soil environment, among which the balanced application(188.0,53.0 and 50.0 kg/hm2 of N,P and K fertilizers respectively) was the most effective in increasing the abundance and diversity of A. tricolor inter-root soil bacteria and fungi and improving the microenvironment of A. tricolor inter-root soil. It can be applied in the production of A. tricolor. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to screen antagonistic bacterial strains of mango anthracnose, so as to lay a theoretical basis for biological control of mango anthracnose and provide strain resources.【Method】Colletotrichum asianum,the dominant species of mango anthrax, was used as the target, and 37 strains of Bacillus spp. obtained in previous studies were used for confrontation culture and in vitro inoculation test. The antagonistic strains with obvious control effect were selected and their antagonistic mechanism was analyzed.【Result】The results of confrontation test showed that the inhibitory rates of 10 antagonists against C. asianum were more than 78.00%,among which the inhibitory rates of M12-5,L18-7,L19-3,L17-3 and M11-6 reached 96.24%,94.94%,94.10%,91.25% and 90.00%,respectively. Eight strains of Bacillus spp. with obvious control effect were obtained by in vitro inoculation, among which strains L18-7 and L16-4 had the best control effect, with the average control efficiency of 83.00% and 79.16%,respectively. There was no significant difference between them(P＞0.05). Combined with morphological characteristics, 16S rDNA sequence and phylogenetic tree analysis based on rpoB gene sequence, strain L18-7 could be identified as B. velezensis. Strain L18-7 could produce extracellular protease and cellulase, and could produce active antagonists in five media including Luria-bertani(LB),beef peptone(NA) and potato glucose agar(PDA) etc. Strain L18-7 carried genes related to antibiotic production such as mycB,ituA,yndJ,fenB and bacA.【Conclusion】The antagonistic bacterium strain L18-7 of mango anthracnose was identified as B. velezensis. The strain grew well on LB medium at 28 ℃.It could produce antagonistic substances, extracellular protease and cellulase and carried related genes of antibiotics such as mycB,ituA,yndJ,fenB and bacA. It can be used as germplasm resources for biocontrol bacteria. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to further clarify the mechanism of tobacco continuous cropping obstacles and explore the relationship between tobacco continuous cropping obstacles, rhizosphere microbial structure and rhizosphere metabolites. 【Method】The study analyzed the microbiome and metabolome of short-term continuous cropping and non-continuous tobacco rhizosphere soil materials using Illumina high-throughput sequencing technology and UPLC-ATOF MS liquid-mass spectrometry technology. 【Result】There was no significant difference in the diversity of rhizosphere bacteria among different varieties and between continuous cropping and non-continuous cropping soils. Short-term continuous cropping had no significant effect on the structure and diversity of rhizosphere bacteria, but the abundance and uniformity of rhizosphere fungal was significantly reduced along with the continuous cropping. The fungal diversity in the non-continuous cropping rhizosphere soil was significantly higher than that in the short-term continuous-cropping rhizosphere soil. The abundance of Olpidium brassicae and Fusarium equiseti increased significantly in short-term continuous cropping rhizosphere soil, while the abundance of Mortierella elongata decreased significantly. LEfSe showed that fungus in Fusarium were markers of significant difference between short-term continuous cropping and non-continuous tobacco rhizosphere soil. Metabolome analysis found that organic nitrogen compounds, sphingolipids, terpenoids, steroids and steroid derivatives were significantly different metabolites between short-term continuous cropping and non-continuous tobacco rhizosphere soil. Among them, the rhizosphere soil of short-term continuous cropping was significantly enriched in free amino acids and alkaloids such as berberine, solanine, and vinasse, indicating that fungal infection and autotoxic effects have been produced in the short-term continuous cropping tobacco rhizosphere soils.【Conclusion】The study preliminarily analyzed the relationship between rhizosphere microorganisms and metabolites under short-term continuous cropping of tobacco. Although short-term continuous cropping has little effect on the rhizosphere bacterial community, the allelopathic effect of rhizosphere secondary metabolites can quickly and significantly change the structure of rhizosphere fungal community, leading to rapid reproduction of pathogenic fungi. [ABSTRACT FROM AUTHOR]

【Objective】The aim of this paper is to analyze the genetic diversity of faba bean germplasm resources by transcriptome sequencing and SSR molecular marker technology， and to explore the molecular markers associated with bruchid resistance traits in faba bean. So as to provide a reference basis for the conservation and utilization of bruchid resistance germplasm resources and the selection and breeding of new varieties. 【Method】Transcriptome sequencing of two faba bean varieties Y134 and Y078 was performed by PacBio triple full-length sequencing technology combined with RNA-seq.. Based on this， all Unigene of the transcriptome were searched for Unigene containing SSR core motifs using the software MISA， and primers were designed in batch using Primer 3.0. One hundred pairs of SSR primers were randomly selected for genetic diversity analysis of 80 faba bean germplasm resources. 【Result】Fifty of the 100 SSR primer pairs amplified products， with an effective amplification rate of 50%; 32 of the primer pairs showed polymorphism. They accounted for 64% of the effective products and 32% of the total primers. Among the 32 polymorphic primer pairs， each pair amplified 2 to 21 alleles with an average of 6.875; The polymorphic information content （PIC） values ranged from 0.25 to 0.82 with an average of 0.58; The Shannon’s information index varied from 0.34 to 2.31 with an average of 1.21. Based on UPGMA cluster analysis， the 80 faba bean materials were classified into two major groups at a similarity coefficient of 0.70. The first category contained 65 germplasm， including 62 highly resistant （HR） varieties， 2 highly sensitive （HS） varieties and 1 sensitive （S） variety; The second category contained 15 germplasm， 7 highly susceptible （HS） varieties， 2 sensitive （S） varieties， 5 highly resistant （HR） varieties and 1 moderately resistant （MR） variety. 【Conclusion】The SSR markers developed were used to analyze the genetic diversity of 80 faba bean germplasm resources and to lay the theoretical foundation for research on the identification of faba bean germplasm resources resistant to bean weevil and molecular marker-assisted selection for breeding. [ABSTRACT FROM AUTHOR]

【Objective】The paper aimed to study the reduction of antibiotic resistance genes（ARGs） in pig manure during composting.【Method】Pig manure and mushroom residue were used as fermentation materials for aerobic composting. On the 1st, 4th, 8th, 12th, 16th, 22nd and 29th day of composting, the multi-point sampling was carried out in upper, middle and lower layers to extract total DNA and construct the library.Macrogenomic sequencing analysis was carried out after quantification and qualified detection.The dynamic changes of ARGs during composting were analyzed by metagenomic sequencing.【Result】A total of 613 ARGs were found during composting, which were resistant to 32 classes of antibiotics.Among them, Penam, Cephalosporin, Aminoglycoside, Fosfomycin, Glycopeptide and Tetracycline was more abundant. This was consistent with the types of antibiotics commonly used in reality.Analysis found two peaks in depletion of ARGs. The first peak appeared at the beginning of the trial, declined rapidly on the 4th day, then reached a second peak on the 12th（control group） and 8th day（experimental group）.With the natural apoptosis of bacteria, the abundance of ARGs dropped to a low value and gradually decreased.【Conclusion】During composting, the ARGs in pig manure decreased in a fluctuating manner. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the effects of different proportions of red and blue light on flower bud differentiation of ‘Red Globe’ grape in facilities, and to solve the problem of poor flower bud differentiation of ‘Red Globe’ grape caused by low light environment in facilities.【Method】Taking ‘Red Globe’ grape as experimental material, without light supplement as control（CK）, the effects of red and blue light on flower bud differentiation were explored by LED light treatment of red（R）, blue（B）, red and blue 2∶1（R2B1）, red and blue 4∶1（R4B1） and red and blue 6∶1（R6B1）, together with the study of histology, physiological indexes and floral gene expression.【Result】Different proportions of red and blue significantly affected flower bud differentiation and flower related gene expression of facility ‘Red Globe’ grape.R4B1 and R6B1 treatments significantly increased the flowering rate of ‘Red Globe’ grape in greenhouse.Among them, under R4B1 treatment, the flower bud differentiation rate was fast, and the flowering rate was the highest, reaching 66% in the fifth section. The contents of carbohydrate, soluble protein and flavonoid in leaves increased, and the flowering genes VvFUL, VvFT, VvAG, VvAP1, VvAP2, VvSOC1 and VvSPL10 were up-regulated, while VvLFY and VvFLC were down-regulated.The correlation analysis between flowering genes and flowering rate showed that the flowering rate under R4B1 treatment was positively correlated with the expression levels of VvFUL, VvFT, VvAG and VvSPL10, and VvAP1 was positively correlated with VvFT, and negatively correlated with VvAP2 and VvAP3.VvFLC was negatively correlated with VvAG, and VvFT was positively correlated with VvAP2, VvSOC1 and VvSPL10.Network interaction analysis showed that the presentation and total correlation of VvAP1, VAP2 and VvSOC1 were high, and VvAP1, VvAP2, VvSOC1 and VvLFY were the critical nodes of flowering gene interaction.【Conclusion】R4B1 treatment significantly increased leaf nutrient accumulation and floral gene expression in the ‘Red Globe’ grape and promoted flower bud differentiation. These results can provide a reference for further understanding the physiological and molecular mechanisms of red and blue light regulating flower bud differentiation of ‘Red Globe’ grape, and provide a theoretical basis for improving flower bud differentiation of ‘Red Globe’ grape. [ABSTRACT FROM AUTHOR]

【Objective】The present paper investigated the effects of ABA on the fruit quality of cucumber to offer operation instruction and theoretical basis in the fruit improvement via exogenous ABA.【Method】Huabei cucumber variety ‘Chuancui No.13’ was used as materials and the method of foliar spraying was used. The effects of spraying different concentration of ABA（0, 50, 100, 200 and 400 μmol/L） on the soluble sugar, ascorbic acid and flavor substance trans-2,cis-6-Nonadienal of the cucumber fruit were studied.【Result】Foliar spraying 50-200 μmol/L ABA promoted the accumulation of soluble sugar and ascorbic acid content, but decreased the content of flavor substance. Foliar spraying 400 μmol/L ABA decreased the ascorbic acid content significantly. To further analyze mechanism of ABA influencing the quality of cucumber, RNA-seq was performed to analyze the cucumber fruit. A total of 169 differentially expression genes（DEGs, 94 genes were up-regulated, and 75 genes were down-regulated） were found after the foliar ABA application in the cucumber fruit compared to the control.Gene ontology（GO） enrichment showed that multiple DEGs were involved in transcription regulation and regulation of macromolecule biosynthetic process.KEGG pathway enrichment showed that most DEGs participated in biosynthesis and hormone signaling pathway, suggesting that exogenous ABA affected cucumber fruit quality via macromolecule biosynthesis and hormone signaling pathway. In addition, expression level of 44 transcription factors was influenced by exogenous ABA application, including TFs from families of bHLH, bZIP, FAR1, MYB and NAC.【Conclusion】The research investigated effect of foliar spraying ABA on quality and transcriptome profiling changes of cucumber fruit and proposed that exogenous ABA affected genes expression at transcription levels to positively regulate soluble sugar and ascorbic acid content and negatively regulate accumulation of flavor substance. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to clarify the comprehensive soil fertility status of pitaya orchards in Hainan province, and the spatial distribution and changing trend of soil nutrients in pitaya orchards in Hainan province were analyzed and predicted by means of survey sampling and statistical methods, so as to provide the basis for scientific fertilization and soil management of pitaya orchards.【Method】60 soil samples were collected from pitaya orchards in the main producing areas of Hainan province.Soil pH, organic matter, available nitrogen, available phosphorus, available potassium, exchangeable calcium, exchangeable magnesium, available copper and available zinc were used as evaluation indicators.Inverse distance weight interpolation method（IDW） was used to analyze the spatial distribution of each index, and used the factor analysis method combined with IDW to evaluate and predict the comprehensive soil fertility of the pitaya orchards in the survey area.【Result】The orchard soil in the survey area was neutral and slightly acidic, and 50% of the soil samples, pH were lower than 6.5; The organic matter content was moderately low, and some areas of Ledong and Sanya were insufficient; The average value of alkaline hydrolysis nitrogen was only 79.17 mg/kg, and the soil in the survey area was relatively lack of alkali-hydrolyzable nitrogen; The content of available phosphorus and available potassium were both high, and the average available phosphorus was 119.06 mg/kg, far exceeding its environmental risk threshold（60 mg/kg）; Orchards in the survey area the content of trace elements in the soil was relatively abundant. The IDW prediction map showed that the content of trace elements in Dongfang and Lingshui was high, and the content of Ledong and Sanya was low; Based on the analysis of the comprehensive score IFI, the results of the comprehensive fertility prediction of pitaya orchards in the entire study area using IDW showed that the eastern part of the study area, the comprehensive soil fertility of the orchards in the eastern and western regions of the study area was relatively high, while the soil comprehensive fertility of the orchards in the central part of Ledong and Sanya was relatively low.【Conclusion】The pitaya orchards in Ledong and Sanya still need to increase the input of organic fertilizers or increase the application of lime to improve the soil pH and supplement the medium and trace elements; The orchards in the survey area need to increase the input of nitrogen fertilizer and control the application of phosphate fertilizer. [ABSTRACT FROM AUTHOR]

【Objective】In recent years, the wheat in Sichuan province is threatened by Fusarium head blight（FHB） or scab as changes in climate and farming practices.The present paper aimed to obtain the genetic resources of resistance to FHB in Sichuan wheat varieties, and breed wheat for resistance to FHB.【Method】In the research, 156 wheat varieties or high-generation lines with moderate resistance to FHB were identified by soil surface inoculation.The resistance gene composition of these wheat varieties was detected by molecular markers of FHB resistance genes Fhb1, Fhb2, Fhb4 and Fhb5, as well as some stripe rust resistance genes and powdery mildew resistance gene.【Result】Through molecular detection of disease resistance genes, it was found that 20yin979 and 20jian2506-10 contained the FHB resistance genes Fhb1 and Fhb5, respectively. For stripe rust resistance genes detection, 4, 63, 9, 3 and 14 wheat materials containing the Yr5, Yr15, Yr18, Yr26 and YrAs2388 were detected, respectively. And the distribution frequencies of rust resistance genes Yr5, Yr15, Yr18, Yr26 and YrAs2388 were 2.56%, 40.38%, 5.77%, 1.92% and 8.97%, respectively. A total of 44 materials containing the powdery mildew resistance gene Pm21 were detected, and the distribution frequency in the tested materials was 28.21%.The distribution of resistance genes showed that 122 materials contained at least one resistance gene.Among them, 6 materials contained both strip rust and powdery mildew resistance genes, 9 materials contained 2 strip rust resistance genes, and the remaining 106 materials contained only 1 resistance gene. The only material 20jian2506-10 contained three resistance genes of FHB, stripe rust and powdery mildew.【Conclusion】These results indicate that Sichuan wheat lacks FHB resistance resources with explicit genetic background.Therefore, Sichuan wheat FHB resistance breeding should strengthen the introduction of known resistance resources while making full use of the local FHB resistance resources. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to analyze the effects of endophytic fungus Y118 on the growth promotion and quality of its host, Zanthoxylum nitidum（Rox.） DC,so as to provide a reference for improving comprehensive benefits of Z.nitidum.【Method】Z.nitidum plants were cultured with endophytic fungus Y118 solid fermentation medium.The growth indexes（fresh weight, plant height, stem base width, stem middle width and fresh and dry weight of roots, stems and leaves） of Z.nitidum plants were measured at different growth stages.The contents of nitrine chloride and chelidonine in roots of Z.nitidum were determined by chromatographic method.【Result】After 3 months of culture, the fresh weight, plant height, stem base width and stem middle width of the fungus Y118 treatment group were 34.76 g, 34.47 cm, 6.54 mm and 4.25 mm, respectively, which were extremely significantly higher than those of the control group（P＜0.01,the same as below）.The fresh weight and dry weight of roots, stems and leaves were significantly increased（P＜0.05,the same as below） or extremely significantly increased.After 6 months of culture, the fresh weight and plant height of Z.nitidum were 68.33 g and 47.85 cm, respectively, which were extremely significantly higher than control group. The fresh weight and dry weight of roots, stems and leaves were extremely significantly increased. After 9 months of culture, the fresh weight, plant height and stem base width of Z.nitidum treated with fungus Y118 were 73.80 g, 49.22 cm and 9.79 mm, respectively, which were extremely significantly higher than those of the control group. The fresh weight and dry weight of roots, stems and leaves were extremely significantly increased. After 12 months of culture, the fresh weight of Z.nitidum in Y118 treatment group was 78.71 g, which was extremely significantly higher than control group, and the fresh and dry weight of root, stem and leaf were significantly increased or extremely significant. After 9 and 12 months of co-culture, Z.nitidum alkali content in fungus Y118 treatment group was 0.783 and 0.904 mg/g, respectively, which increased by 42.11% and 44.18% compared with the control group. The content of chelidonine at 9 and 12 months of co-culture were 3.704 and 4.201 mg/g, respectively, which increased by 40.73% and 26.57% compared with the control.【Conclusion】Inoculation of endophytic fungus Y118 could significantly or extremely significantly increase the fresh weight, plant height, stem base width and stem middle width of Z.nitidum seedlings, which was beneficial to promote the growth and development of Z.nitidum seedlings, and could improve the fresh and dry weight and quality of roots, stems and leaves. It can provide the basis for the field production test of Z.nitidum. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to study the saline-alkaline stress on the content of lignin, chlorophyll, as well as the genes expression levels in lignin and chlorophyll biosynthetic pathways, to provide a theoretical reference for revealing the molecular response mechanism of maize in response to saline-alkaline stress and cultivating new saline-alkaline-resistant maize varieties.【Method】Corn seedlings were treated with saline-alkali stress, and high-throughput transcriptome sequencing was conducted.The chlorophyll and lignin content were detected.【Result】In total, 39 722 genes were identified, including 5659 differentially expressed genes.The differentially expressed genes were mainly annotated in carbon metabolism, phenylpropanoid biosynthesis, starch and sucrose metabolism pathways.Under saline-alkaline stress, the chlorophyll content and lignin content were reduced by 30.45% and 31.26%, both H-type and S-type monolignol reduced, while G-type monolignol increased.The analysis of the relationship between gene expression level and component content showed that, the down-regulation of chlorophyll/bacteriochlorophyll synthase, and up-regulation of chlorophyllase and chlorophyll（ide） b reductase led to the reduction in chlorophyll content.The 161 DEGs in ‘phenylpropanoid biosynthesis’ pathway may cause the variation in lignin and monolignol content.【Conclusion】Saline-alkalines reduce the total lignin content mainly by inhibiting the biosynthesis of H-type and S-type monolignol.Saline-alkaline reduces the chlorophyll content probably by down-regulated chlorophyll/bacteriochlorophyll synthase genes, and up-regulated chlorophyllase and chlorophyll（ide） b reductase genes.Overall, the study provides a theoretical basis for improving saline-alkaline resistance and controlling lignin content of maize by molecular breeding. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to establish the evaluation method of heat resistance of leek resources, select heat-resistant leek varieties, and solve the problem of shortage of heat-resistant leek varieties in Guangxi.【Method】Taking three kinds of local germplasm resources of leek（marked as A, B, C, D, E, F, G, H and I, respectively） of Guangxi large leaf leek, wide leaf leek and thin leaf leek collected from the general survey of germplasm resources by Ministry of Agricultural and Rural Affairs（2015-2020） as test materials, the changes of the maximum growth length of leek leaves, the newly increased aboveground biomass and the contents of chlorophyll, proline and malondialdehyde after 7 days of high temperature stress at 38 ℃ were measured. Combined with field natural high temperature stress（field group） actual heat resistance performance, the heat resistance of different types of leek was comprehensively evaluated by multivariate statistical analysis（variance analysis, principal component analysis, membership function method and cluster analysis） methods.【Result】Under high temperature stress of 38 ℃,the maximum leaf growth length and the newly increased biomass of 9 leek germplasms of the three types in Guangxi were extremely significantly decreased compared with their proper temperature control（CK）（P＜0.01）.The largest decline was the type of large-leaved leek, and the smallest decline was the type of fine-leaved leek. Chlorophyll content decreased to different degrees, of which the largest decline was the type of leek with large leaves, and the smallest decline was the type of leek with thin leaves. The content of MDA increased to different degrees, of which the largest increase was the type of leek with large leaves, and the smallest increase was the type of leek with thin leaves. Pro content increased to different degrees, of which, the largest increase was the type of leek with thin leaves, and the smallest increase was the type of leek with large leaves. The comprehensive evaluation results showed that the heat tolerance of the three kinds of local leek germplasm resources of leek in Guangxi was ranked as follows: leek with thin leaves＞leek with broad leaves＞leek with large leaves. Germplasm G（No.2016451159） and Germplasm I（No.2016453604） had the strongest heat tolerance among the nine leek germplasms, and Germplasm C（No.SC20191200） had the weakest heat tolerance.【Conclusion】The maximum growth length of leaves, new aboveground biomass and the content of chlorophyll, Pro and MDA contents were used as the evaluation indicators of heat tolerance of leek germplasm resources, the heat tolerance of three kinds of leek germplasm resources in Guangxi can be ranked as follows: Leek with thin leaves＞ leek with broad leaves＞leek with large leaves by variance analysis, principal component analysis, membership function and cluster analysis. Germplasm G and germplasm I were determined to be more heat-resistant, while germplasm C was the least heat-resistant. [ABSTRACT FROM AUTHOR]

【Objective】Through exploring the chlorophyll content SPAD value and chlorophyll fluorescence characteristics of the leaves of 57NG208 F1 generation germplasm of Saccharum robustum, the purpose of the present paper is to lay a foundation for the breeding of sugarcane with the germplasm of S. robustum with high light-use-efficiency varieties or parents. 【Method】The F1 population of S. robustum 57NG208 was used as the test material, and the portable SPAD-502 chlorophyll meter and portable fluorescence meter（PAM-2500） were used. Correlation and cluster analyses were carried out for SPAD value representing chlorophyll content, initial fluorescence（Fo）, maximum fluorescence（Fm）, maximum photochemical efficiency（Fv/Fm）, actual photochemical efficiency Y（Ⅱ）, non-photochemical quenching coefficient（NPQ） and photochemical quenching coefficient（qP）. 【Result】The difference of 8 photosynthetic indexes in 120 germplasm materials of sugarcane leaves was highly significant; The results of correlation analysis showed that the potential photochemical efficiency（Fv/Fo） was positively correlated with the maximum photochemical efficiency（Fv/Fm）, the photochemical fluorescence quenching coefficient（qP） and non-photochemical fluorescence quenching coefficient（NPQ） were negatively correlated, the Y（Ⅱ） value was positively correlated with the SPAD value of chlorophyll content, and the rest of indexes were positively correlated. Based on the Y（Ⅱ） value of the actual photochemical efficiency of 120 germplasm materials, the samples were divided into three categories: Namely low light energy conversion efficiency type（class Ⅰ）, medium light energy conversion efficiency type（class Ⅱ）, and high light energy conversion efficiency type（class Ⅲ）. 【Conclusion】In 120 germplasm F1 of S.robustum 57NG208, thirteen materials, which were Yunrui 19-8-43, Yunrui 19-8-54, Yunrui 19-8-62, Yunrui 19-8-64, Yunrui 19-8-106, Yunrui 19-8-44, Yunrui 19-8-2, Yunrui 19-8-108, Yunrui 19-8-38, Yunrui 19-8-57, Yunrui 19-8-26, Yunrui 19-8-50, Yunrui 19-8-107, belonged to high light efficiency germplasm, that should be used as germplam pool for breeding. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore which proportion of nitrogen and phosphorus fertilizer combined with drip irrigation water and fertilizer integration in the Yellow River Diversion Irrigation Area can promote the accumulation and transfer of spring maize dry matter in Yinchuan Plain, and its effects on fertilizer utilization rate and yield, so as to provide a basis for the integration of drip irrigation water and fertilizer for spring maize in the Yellow River Diversion Irrigation Area. 【Method】The experiment was carried out in the Yinchuan Plain of the Yellow River Irrigation Area from 2019 to 2020. The maize variety Yinyu 274 was used as the material. The conventional application rates of local nitrogen and phosphorus fertilizers were 417 and 142.50 kg/hm². The conventional application rate of 70% nitrogen and phosphorus fertilizer was 291.90 and 99.75 kg/hm2. The conventional application rates of 130% nitrogen and phosphorus fertilizer were 542.10 and 185.25 kg/hm2. Six treatments with different proportions of nitrogen and phosphorus fertilizers were set up as T1 （N 0, P 0）, T2 （N 100%, P 70%）, T3 （N 100%, P 100%）, T4 （N 70%, P 100%）, T5 （N 130%, P100%）, T6 （N 100%, P 130%）. The effects of different ratios of nitrogen and phosphorus combined application on the dry matter accumulation, dry matter transport, grain contribution rate, nutrient utilization rate and yield of maize under drip irrigation, water and fertilizer integration were analyzed.【Result】The combined application of nitrogen fertilizer 291.9 kg/hm2 and phosphorus fertilizer 142.50 kg/hm² under the combined application of six kinds of nitrogen and phosphorus fertilizers had the best overall effect. The absorption of phosphorus and nitrogen by maize was significantly higher than that of other treatments. The nutrient requirements of maize throughout its growth period were satisfied. Compared with other treatments, the dry matter accumulation increased by 6.28%-22.90%, and the dry matter transport and grain contribution rate increased by 4.60%-11.10%. Compared with conventional combined application, nitrogen fertilizer utilization rate, phosphate fertilizer utilization rate, nitrogen fertilizer partial productivity and phosphate fertilizer partial productivity were significantly increased by 52.23%, 18.92%, 57.07% and 9.95% in T4 treatment. It can also significantly improve the corn ear formation rate, the number of grains per ear, and the weight of 100 kernels, thereby increasing the yield. The yield could be increased by 8.34%-9.95% compared with the conventional nitrogen and phosphorus application, and the maximum yield was 21 916.39 kg/hm².【Conclusion】The combined application of nitrogen fertilizer 291.90 kg/hm² and phosphorus fertilizer 142.50 kg/hm² under drip irrigation water and fertilizer integration in the Yellow River Diversion Irrigation Area can significantly increase the dry matter accumulation before and after flowering, and improve the dry matter transport, transport rate and contribution to seeds, and improve N fertilizer utilization, phosphorus fertilizer utilization and N fertilizer bias productivity, thus increasing maize yield. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to analyze the relationship between maize rhizosphere soil and maize growth and development under different continuous cropping years, and discuss the effects of continuous cropping on the growth and development of maize and the physicochemical properties and enzyme activities of rhizosphere soil.【Method】The agronomic characters of maize, the physicochemical properties of rhizosphere soil and the enzyme activities of maize were measured in Xinglong Village, Shajing Town, Ganzhou District, Zhangye City, Gansu Province, respectively for 1, 5, 11, 25 and 50 years of continuous cropping. The variance analysis of the experimental data was carried out using SPSS22.0 software.【Result】Hydrolyzable nitrogen decreased first and then increased with the extension of continuous cropping years, and available phosphorus, available potassium and pH increased first and then decreased with the extension of continuous cropping years; The activities of S-SC, S-UE, S-AKP/ALP and S-CAT in the rhizosphere soil of maize under different continuous cropping years were significantly different, all of which increased first and then decreased with the extension of continuous cropping years; The effects of continuous cropping on the aboveground biological characteristics of maize were significantly different. Among them, the growth of maize in rotation for one year was relatively uniform, and the chlorophyll content was high. The photosynthesis of maize in continuous cropping for 11 years was the strongest, the root system was well developed, the hairy root was long, and the distribution was uniform on the main root; Soil available phosphorus, available potassium, weak alkaline soil, S-AKP/ALP and S-SC could promote the root development of maize.【Conclusion】Continuous cropping leads to the decline of corn agronomic traits, the loss of available phosphorus and available potassium in the soil, the enrichment of hydrolytic nitrogen, and the acidification of the soil. Soil available phosphorus, available potassium, weak alkaline soil, S-AKP/ALP and S-SC can promote the development of maize roots. The increase of hydrolytic nitrogen, soil urease （S-UE） and soil catalase （S-CAT） was not conducive to maize root development. [ABSTRACT FROM AUTHOR]

【Objective】The paper aimed to express the NS1 and VP2 proteins of chicken parvovirus（ChPV） in prokaryotes and prepare polyclonal antibodies against them, which would provide material basis for further study of the protein structure and function of chicken parvovirus（ChPV） and provide materials for the establishment of serological diagnostic methods. 【Method】In the study, the sequences of NS1 and VP2 gene of chicken parvovirus GX-Ch-PV-21 strain were synthesized. The prokaryotic recombinant expression vectors pET-32a-NS1 and pET-32a-VP2 were constructed, and the correct recombinant plasmids were transformed into transsetta competent cells for prokaryotic expression. The expression conditions were optimized, and the expressions of NS1 and VP2 proteins were identified by SDS-PAGE and Western-blotting. The expression products were immunized to SPF chickens to obtain polyclonal antibodies. The titer of chicken polyclonal antibodies was determined by enzyme linked immunosorbent assay（ELISA）,and the polyclonal antibodies were identified by Western-blotting and indirect immunofluorescence assay（IFA）. 【Result】SDS-PAGE analysis showed that the size of NS1 and VP2 protein bands was about 104 and 87 kD,respectively, which was consistent with the expected size. The optimal induction conditions were screened for the recombinant plasmids pET-32a-VP2 and pET-32a-NS1. The results showed that the optimal induction conditions for the expression of NS1 protein were as follows: The final concentration of isopropyl 1-thio-β-D-galactopyranoside（IPTG） was 1. 0 mmol/mL and the expression was induced overnight at 16 ℃. The optimal conditions for the induction of VP2 protein expression were as follows: The final IPTG concentration was 0. 8 mmol/mL and the expression was induced overnight at 20 ℃. The soluble analysis showed that both NS1 and VP2 proteins mainly existed in the form of inclusion bodies. The titers of polyclonal antibodies against NS1 and VP2 by indirect ELISA were 1∶10 240 000. Western-blotting analysis showed that His tag protein and its corresponding chicken polyclonal antibody could specifically bind to NS1 and VP2 proteins. The IFA analysis showed that both VP2 and NS1 polyclonal antibodies could specifically bind to ChPV. 【Conclusion】In the study, the NS1 and VP2 proteins of chicken parvovirus were successfully expressed, and the chicken anti-polyclonal antibody was successfully prepared, which provided material basis for further study of the structure and function of chicken parvovirus protein and materials for the establishment of serological diagnostic methods. [ABSTRACT FROM AUTHOR]

【Objective】The advantages of several classifiers were combined to improve the accuracy of crop information extraction from remote sensing images.【Method】The paper took Weiku Oasis as the research area, used the domestic GF-2 data and field survey data, and formulated different classification schemes based on the extracted remote sensing identification features.Five traditional machine learning methods as Mahalanobis distance (MsDC), minimum distance (MDC), maximum likelihood (MLC), neural network (NNC), and support vector machine (SVM) were used to classify the images of the six feature combination schemes.Then the base classifier was selected, and two multi-classifier integration algorithms, the majority voting method and the conservative voting method were applied to finely classify and extract the crops in the study area.【Result】 (i) The additional auxiliary features significantly improved the accuracy of sub-classifiers.Among the five classifiers, except MLC, the other four classifiers achieved the highest accuracy after adding NDVI and texture features. (ii) The most accurate base classifier was NNC-4 (the fourth feature combination scheme of artificial neural network), with OA reaching 83.54% and Kappa coefficient of 0.77. (iii) Compared with the base classifiers, the multi-classifier ensemble method could improve the extraction accuracy of crops in both producer’s accuracy and user’s accuracy.And the conservative voting method was better than the majority voting method, with OA being 85.89% and Kappa coefficient being 0.80. (iv) In the integrated classification results, except that the recognition accuracy of cotton was equal to the optimal base classifier NNC-4, reaching 94.94%, the recognition accuracy of other crops such as interplanted cotton, corn, interplanted corn and walnut orchards was higher than that of NNC-4.Among them, the extraction accuracy of interplanted corn and walnut orchard was better, with the accuracy reaching 86.05% and 79.09% respectively; The extraction of interplanted cotton was poor, only 63.86%; The extraction of corn was the worst, only 12.17%.【Conclusion】In the study, the GF-2 data was applied, and the multi-classifier ensemble method was used to conduct fine extraction research on various crops and planting structures under complex backgrounds, which expanded the direction of crop information extraction and the application field of GF-2 data. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to study the impact of organic and inorganic combined application on the organic carbon composition, carbon bank management index and organic carbon functional group of tobacco planting soil in Wuxi county, so as to provide reference for improving the quality of tobacco planting soil and reasonable fertilization. [Method] Four treatments were set up under the condition of constant nitrogen input in field experiment: chemical fertilizer（CF）, chemical fertilizer with mushroom slag organic fertilizer（CMO）, chemical fertilizer with high carbon-based fertilizer（CHB）, and chemical fertilizer with biological organic fertilizer（CBO）. The effect of organic and inorganic application on soil carbon reservoir was studied by measuring total organic carbon and active carbon functional group structure using Fourier infrared spectrometry（FTIR）. [Result] （i） Compared with single organic fertilizer, the soil supplemented with organic fertilizer was slightly increased, and there was no significant difference between the treatments, significantly increased the output value on flue-cured tobacco leaf;（ii） The DOC, MBC content of the soil active carbon bank treated with organic fertilizer was significantly higher than that of single chemical fertilizer treatment. Among them, CMO treatment showed the largest increase in soil DOC content, thus being 67. 13%, 12. 84%, and 28. 54% higher than CF, CHB, CBO, respectively. CBO treatment showed the most increase in soil MBC content, with soil MBC content increasing 42. 32% compared to CF and CHB treatment showing 11. 43% higher soil EOC compared to CF;（iii）Among the three organic fertilizers, the DOC distribution of DOC, CMO, CBO, EOC, and the carbon bank management index of CHB treatment was significantly greater than CF and CMO;（iv） The structure difference of each treated organic carbon functional group was small, which mainly included phenols, aromatic hydrocarbons, olefins and mesamides. The relative peak area at 1634 cm-1 was associated significantly positively with soil MBC content, and that at 468 cm-1 was associated significantly negatively with soil TOC content. [Conclusion] Compared with single organic fertilizer, soil organic residue organic fertilizer significantly improved soil DOC and MBC content and high carbon-based fertilizer significantly improved soil EOC content and carbon bank management index. Short-term organic and inorganic distribution had little impact on organic carbon functional groups. However, the peaks at 1634 and 468 cm-1 were significantly associated with the soil TOC and MBC content. At the same time, organic-inorganic fertilizer significantly increased the yield and output value of flue-cured tobacco. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to investigate the inhibition effect of raspberry pulp oil on ultraviolet B (UVB) induced photoaging of human keratinocytes (HaCaT cells) . [Method] The raspberry pulp oil was extracted by supercritical CO2 and its chemical compositions were determined by gas chromatography-mass spectrometry (GC-MS) .The photoaging model was established by UVB, the cell viability of HaCaT cells were determined by CCK-8 method, and the concentrations of matrix metalloproteinase-3 (MMP-3), Collagen type 1 (COL1A1), Interleukin-1β (IL-1β), Interleukin-6 (IL-6), Tumor necrosis factor α (TNF-α), Thioredoxin (Trx) and Superoxide dismutase (SOD) were detected by Enzyme-linked immunosorbent assays (ELISA) and microplate assay. [Result] The analysis of GC-MS showed that raspberry pulp oil consisted of 53 chemical components, mainly including fatty acids, ester of fatty acid, tocopherols, and phytosterols.Oleic acid, linoleic acid, ethyl Z-9-oleate, vitamin E and sterol were closely associated with inhibition effects of raspberry pulp oil on photoaging of UVB-induced HaCaT cells.Compared with the model group, raspberry pulp oil significantly improved the cell viability of photodamaged HaCaT cells induced by UVB (P＜0.01) and showed in a does-dependent manner.In addition, raspberry pulp oil significantly increased concentrations of COL1A1 and reduced the concentrations of MMP-3 to promote skin elasticity (P＜0.05, P＜0.01), reduced the levels of IL-1β, IL-6 and TNF-α to alleviate the inflammatory response (P＜0.05, P＜0.01), increased the contents of Trx and SOD to improve skin oxidative stability (P＜0.05, P＜0.01) in the UVB-induced photodamaged HaCaT cells. [Conclusion] Raspberry pulp oil exhibits good anti-photoaging activity probably by alleviating inflammatory reactions, easing the degradation of extracellular matrix components and reducing oxidative stress in the photodamaged HaCaT cells. [ABSTRACT FROM AUTHOR]

[Objectiv] The present paper aimed to study the changes of photosynthetic performance at different stages during the whole growth period after summer flooding, and to reveal the adaptation mechanism of photosynthetic performance of the Salix variegata Franch populations to the changes of aquatic ecological environment, so as to provide scientific basis for the protection and utilization of this species. [Method] In the study, the S. variegata Franch populations in Guanzhou Island, downstream of the Three Gorges Dam, were used as the test materials. By using the method of field investigation and measurement, different gradient measurement times were set: at the initial stage of exposure (exposure for 60 days）, every 10 days, and at the early, middle and late stages of the whole growth period (exposure for 50 days, 110 days and 170 days）, the photosynthetic performance of the plants were measured respectively, in order to reveal the effects of artificial regulation of rivers on the photosynthetic performance of plant populations and plant growth. [Result] The photosynthetic performance of the S. variegata populations recovered rapidly during the early exposing stage under the regulated water level fluctuation pattern. The photosynthetic rate (Pn）, stomatal conductance (Gs) and transpiration rate (Tr) of plants increased significantly with the growth recovery process. The characteristic values of light response curves including the maximum net photosynthetic rate(Pn max), apparent quantum efficiency (AQY) and photosynthetic pigment content also increased rapidly. The photosynthetic performance of the populations ranked the highest at the early growth stage, followed by the late and middle growth stage in the whole growth period. The net photosynthetic rate increased by 59. 39% and 30. 77% compared with that of the middle and late growth stages, respectively. A similar trend of variation in the characteristic values of light response curve and photosynthetic pigment content was also observed. Pearson correlation analysis indicated that the related parameters of photosynthetic performance of S. variegata populations were significantly correlated with soil water content, and the transpiration rate and carotenoid content were significantly correlated with water level. [Conclusion] The decrease of soil water content and exposing time caused by the river regulation by the large-scale water conservancy and hydropower projects had a serious impact on the photosynthetic performance of S. variegata populations, and further affected the growth of the populations. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the effects of different leaf numbers and curing methods on the safety and aroma quality of cigar filler leaves. [Method] The traditional cigar filler variety Shiyan No. 1 was used as the material, and the remaining leaves were 14 and 18 leaves per plant, the curing methods were air-cured and sun-cured. The content of TSNAs and their precursors of the samples before and after curing were determined, as well as neutral aroma component content and sensory quality. [Result] (i) When 14 leaves were left, the leaf thickness, unit area leaf weight and single leaf weight of cigar filler leaves were significantly higher than the treatment with 18 leaves per plant. The tolerable tensile force was also larger, which was more than 10% higher than the 18 leaves treatment. The number of remaining leaves contributed significantly to the changes in physical characteristics of the cigar filler leaves. (ii) The content of TSNAs precursors in cigar filler with 14 leaves per plant was higher. On this basis, the alkaloids content of sun-cured tobacco leaves was the highest. The change of nitrite content in cigar filler was mainly affected by the curing methods, and the air-cured tobacco leaves were higher than that after sun-cured. The number of remaining leaves had a greater contribution to the change of TSNAs content in cigar filler, and the remaining 14 leaves treatment were significantly higher than the remaining 18 tobacco leaves. In addition, leaves after air-cured had the highest TSNAs content, which was 1722. 62 ng/g. (iii) The total amount of carotenoid degradation products, aromatic amino acid degradation products, and browning reaction products of the remaining 18 tobacco leaves after air-cured were higher than those after sun-cured. (iv) The sensory evaluation results showed that the cigar style of the cigar filler leaves under the condition of 18 leaves left and air-cured system was more prominent. Apart from this, the aroma quality was better, the odor was lighter, the aftertaste was better, and the irritation was less. [Conclusion] Shifang traditional cigar filler leaves have a harmonious chemical composition, good aroma components and excellent smoking quality under the condition of 18 leaves left and air-cured, which is conducive to achieving high quality and low harm. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to study the effect of physicochemical properties of rhizosphere soil on quality of Coptis deltoidea C. Y. Cheng et Hsiao and further to provide scientific basis for ecological planting of C. deltoidea. [Method] Eighteen soil physicochemical indexes and six alkaloids of C. deltoidea were determined by soil agrochemical analysis and high performance liquid chromatography (HPLC) . Meanwhile, correlation analysis and redundancy analysis were used to reveal the relationship between physico-chemical properties of soil and the accumulation of alkaloids in C. deltoidea. [Result] The total contents of 6 alkaloids in taproots of C. deltoidea that grew for two to five years old were 3. 716%, 5. 720%, 8. 552% and 8. 866%, respectively, and the contents of berberine were 1. 779%, 3. 620%, 5. 469% and 5. 706%, respectively, which indicated that the four-year-old C. deltoidea had met the harvesting standard. The correlation analysis of alkaloids and soil factors in the taproot of C. deltoidea showed that total amount of 6 alkaloids and berberine content were significantly positively correlated with available potassium (P＜0. 05), and significantly negatively correlated with nitrate nitrogen and sodium (P＜0. 01) . And a significant negative correlation was also seen between sodium and rhizobine (P＜0. 01) . There was significant negative correlation between coptidine and copper (P＜0. 05), and extremely significant negative correlation between coptidine and sodium (P ＜0. 01) . Finally, according to the redundancy analysis of alkaloids in taproot and soil factors, the contents of available phosphorus, available potassium and sodium in soil were the dominant factors affecting the accumulation of alkaloids in C. deltoidea, while ammonium nitrogen and pH were the more important factors. [Conclusion] In the process of planting C. deltoidea, high-quality soil environmental conditions can be selected from the planting source, that is, the soil with high nitrogen and potassium, low phosphorus and sodium and acidic pH can be selected. Moreover, the alkaloid content of C. deltoidea can be regulated by adding potassium fertilizer and nitrogen fertilizer, controlling the application amount of phosphate fertilizer and reducing the content of sodium in the soil. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to analyze the effects of sowing date and film mulching on yield and quality of direct seeding winter rapeseed to provide a theoretical basis for suitable sowing and high-yielding cultivation of winter rapeseed in dryland in southwest China. [Method] A two-factor completely randomized block design was adopted to explore the effect of sowing date(20th September, 30th September, 10th October, 20th October, 30th October, 10th November, 20th November) and film mulching (film mulching and no film mulching) on field soil temperature, dry matter accumulation, agronomic characteristics, yield and quality of Chuanyou 36. [Result] Film mulching effectively increased the 0-20 cm soil temperature, dry matter accumulation, plant height, length of main inflorscence and effective pods, thereby increasing rapeseed yield by 3.61%-44.47%, which was more obvious with the delay of sowing date. However, the sowing date delayed longer, dry matter accumulation and agronomic traits of rapeseed decreased significantly. The regression equation showed that the rapeseed yield rose first and then declined with the delay of sowing date, which had a significant polynomial relationship with sowing date. The optimal sowing date for rapeseed was 10th October, which was 2.13%, 47.97%, 74.19% and 136.64% higher than 30th September, 30th October, 10th November and 20th November, respectively. In addition, the delay of sowing date effectively reduced the content of linolenic acid, erucic acid and glucosinolates in rapeseed, but also reduced the oil content, while film mulching effectively decreased the difference in rapeseed quality resulted from the delay of sowing date. [Conclusion] 30th September to 10th October was a suitable sowing date for high yield of direct seeding rapeseed in dry land in southwest China, and a proper delay of the sowing period in combination with film mulching technology was more conducive to achieving goals of high yield, efficiency and quality. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to establish a BP (Back propagation) neural network (BPNN) automatic recognition system to achieve the standardization and quantification of flue-cured tobacco browning. 【Method】Taken the upper tobacco leaves of Yunyan 87 as a sample, scanning to obtain characteristic information such as tobacco leaf color, established a BP neural network to identify the degree of browning of flue-cured tobacco, and output the discrimination results, and compared the similarity with the results of artificially discriminating the browning of flue-cured tobacco as a reference. Through the analysis and comparison of appearance quality, conventional chemical composition, polyphenol content, TSNAs content and sensory quality changes, the accuracy of the BP neural network automatic recognition system and manual recognition results were veriofied.【Result】Establishing the BP neural network model could accurately identify tobacco browning level, and its recognition accuracy was 98.75%.There was no significant different among grading tobacco appearance quality, routine chemical compositions, polyphenol content, the content of TSNAs and sensory quality of change and the artificial recognition (P＜0.05).Which provided objective evaluation method for noise smoke, and the availability of tobacco leaves with different browning degrees was effectively distinguished.【Conclusion】The accuracy of the BP neural network recognition system for identifying the degree of tobacco browning is close to that of manual recognition. The BP neural network automatic recognition system can be used to replace manual recognition, which provides a reference for promoting the construction of tobacco BP. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to investigate the effects of foliar spraying of different concentrations of urea on light energy utilization, physiological resistance, berry quality and yeast assimilable nitrogen in wine grapes during the color change of wine grapes in the wine production area of the eastern Helan Mountains.【Method】A combination of field trials and indoor analysis was conducted with the wine grape variety 'Cabernet Sauvignon' as the test material in a randomized block design. Urea was sprayed three times at 0‰, 1‰, 1.5‰, 2‰, 2.5‰, 3‰ and 3.5‰ during the color change of grapes, and the related indexes of physiology, quality and yeast assimilable nitrogen of wine grapes were measured, and the results were analyzed by ANOVA and significance test.【Result】During the color change of wine grapes, foliar nitrogen supplementation at appropriate levels significantly improved the berry quality of wine grapes. With the increase of urea concentration, the photosynthetic efficiency, physiology and berry quality of wine grape leaves showed a trend of increasing and then decreasing. The best results for net photosynthetic rate, carotenoids, superoxide dismutase and tannin content of grape leaves were obtained at 2.0‰ concentration spray. They were significantly increased by 36.10%, 38.46%, 14.65% and 19.51%, respectively, compared with the control treatment. Spraying 2.5‰ concentration significantly increased stomatal conductance water utilization, chlorophyll, catalase, spike length, grain size, 100 grain weight, soluble solids, sugar to acid ratio, anthocyanin, total phenols and yeast assimilable nitrogen by 54.53%, 26.32%, 13.66%, 264.61%, 20.99%, 44.47%, 42.55%, 4.50%, 3.18%, 108.13%, 33.71% and 54.85%, respectively, higher than the control treatment. Spraying 3.5‰ concentration significantly increased leaf area, proline and malondialdehyde by 30.80%, 156.21% and 48.04%, respectively, compared with the control treatment.【Conclusion】A comprehensive analysis showed that foliar spraying of urea at a concentration of 2.5‰ during the color change of wine grapes significantly increased the photosynthetic utilization efficiency of leaves, enhanced the physiological resistance of wine grapes leaves, improved berry quality and yeast assimilable nitrogen, and improved the quality of wine grapes berries. In turn, it provided high quality grape raw materials for making high quality wine in the eastern Helan Mountains wine region. [ABSTRACT FROM AUTHOR]

【Objective】The study aimed to explore the ecological security pattern of Kashi region to provide ecological guarantee for regional ecological security protection and sustainable development of oasis region. 【Method】The paper analyzed and identified ecological source sites based on Morphological Spatial Pattern Analysis model and landscape connectivity, applied Minimal Cumulative Resistance model and gravity model to identify and analyze ecological corridors connecting each ecological source site, and combined ecological break-point identification and ecological network analysis to enhance the regional ecological security pattern.【Result】 (i) The ecological patches in Kashi had a high area share and a good ecological safety foundation, but the large number of patches and large area differences led to a large fragmentation of ecological patches and a large ecological safety potential. (ii) The distribution of ecological patches, ecological source sites and core ecological source sites formed an obvious differentiated zoning, and 16 core ecological source sites were finally identified. (iii) 66 ecological corridors with a total length of 5693.356 kilometers were identified, and their role of connecting ecological source sites was good. (iv) The ecological security pattern of 'one source, one corridor, two zones, two belts, three cores and three axes' was proposed, which provided the priority for ecological security protection. 【Conclusion】The construction and restoration of ecological security pattern in Kashi prefecture was of great significance to regional ecological security. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to study the effect of solid-state fermentation of Aspergillus, yeast and lactic acid bacteria on the content and antioxidant activity of polyphenols and flavonoids in freeze-dried figs (Ficus carica L.), and to provide a basis and data reference for the development of functional food or ingredients using figs.【Method】In the study, Aspergillus oryzae, A.niger, Saccharomyces cerevisiae, Rhodotorula glutinis NY5 and Lactococcus garvieae were employed to solid-state fermentation of freeze-dried figs for 7 days.The total contents of phenol and flavonoid, and the in vitro scavenging ability of 1,1-diphenyl-2-trinitrophenylhydrazine radical (DPPH) and reducing ability were determined in the ultrasonic extracts from 0, 1, 3, 5 and 7 days of fermentation by different strains, respectively.The components of polyphenols and flavonoids in the extracts were identified using liquid chromatography-mass spectrometry (LC-MS), and analyzed by principal component analysis (PCA).【Result】The total contents of polyphenol and flavonoid, the antioxidant in extracts fermenting by A.oryzae, A.niger, S.cerevisiae, R.glutinis NY5 and L.garvieae were all increased.Among all tested strains, L.garvieae and A.niger were more capable of increasing polyphenol content than the others.The DPPH radical scavenging and reducing ability of the extracts fermented by L.garvieae were increased by 37.63% and 12.50 times, respectively, compared with that before fermentation.PCA showed that the main compounds produced by the fermented extracts of A.oryzae, A.niger, S.cerevisiae, R.glutinis NY5 and L.garvieae were somewhat different, with the main compounds of A.oryzae and A.niger being flavonoids, S.cerevisiae and S.cerevisiae NY5 being phenols, and L.garvieae having both phenols and flavonoids.【Conclusion】The above results show that it is an effective method to select microbial solid fermentation to improve the content and antioxidant activity of polyphenols and flavonoids in freeze-dried figs.Microbial solid fermentation can effectively improve the contents and antioxidant activities of polyphenols and flavonoids in figs. [ABSTRACT FROM AUTHOR]

【Objective】Since 2017, an anthracnose was extensively occurred on P. cyrtonema in the Hunan province of China. The present paper aimed to clarify the pathogen and the sensitivity of the pathogen to fungicides.【Method】The pathogen fungal stains were isolated from symptomatic leaves and identified by both morphological and molecular tools using both the ITS, ACT, CHS-1 and GPDH gene regions. Pathogenicity was confirmed with inoculation experiments that fulfilled the Koch's postulates. On this basis, the indoor toxicity of 5 fungicides to the pathogen was determined by mycelial growth rate method.【Result】By tissue isolation, 16 morphologically identical strains were isolated from the diseased diseased leaves of four plantation in Hunan province, and the colony morphology and culture characteristics of the strains were observed to confirm that they were Colletotrichum sp.. Molecular identification of CLHJY4-3 determined that the pathogen was C. spaethianum. The pathogenicity was confirmed by inoculation and the Koch's postulates was verified. The average growth rate of the hyphae of this pathogen was 1.1 cm/day. Conidia were 18.4 to 25.0 μm long and 3.9 to 5.3 μm wide. The seta were dark brown, with 2-3 septs, 79-107 μm long. The results of indoor toxicity determination showed that among the five agents, prochloraz had the strongest inhibitory effect on hyphal growth, EC50 was 0.031 μg/mL, followed by pyraclostrobin and tebuconazole, with the EC50 of 0.049 and 0.252 μg/mL, respectively. The inhibitory effects of thiophanate-methyl and carbendazim were relatively poor, with the EC50 of 2.911 and 1.763 μg/mL, respectively. 【Conclusion】C. spaethianum was the pathogen of leaf spot of P. cyrtonema in Hunan province. Moreover, prochloraz and pyraclostrobin were screened as better fungicides against the pathogen fungus. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to identify the pathogen fungus of brown rot of Wushan plum and investigate the inhibitory effect of 1-methylcyclopropene (1-MCP) on it in vivo to provide a theoretical basis for the post-harvest disease control of Wushan plums.【Method】The pathogen fungus was isolated, identified, and pathogenicity tested according to fulfill Koch's postulate. And the isolated and purified brown rot pathogen fungus was inoculated onto plum fruits by damage inoculation to investigate the inhibition effect of 1-MCP treatment on the inoculation of brown rot at different times and fruit firmness in Wushan plum.【Result】The pathogenic fungus was identified as Monilinia fructicola by morphological characterization, fungal universal primers ITS1 and ITS4 combined with PCR technique. During storage at 4 ℃, the incidence of disease and the expansion of spot diameter were suppressed (P ＜ 0.05) in plum fruit inoculated pathogenic bacteria before/after 1-MCP treatment and after injury, 1-MCP treatment was performed before inoculation with pathogenic bacteria(P＜0.05). The inhibitory effect of 1-MCP treatment on brown rot of plum fruit inoculated with pathogen fungus at different periods was not significant at 25 ℃ and was maintained only for 24 hours. Pathogen fungi were more pathogenic to plums under storage at 25 ℃ than under storage at 4 ℃. The 1-MCP treatment was effective in delaying the decline of plums fruit firmness under both ambient temperature and low-temperature conditions.【Conclusion】The pathogen fungus causing postharvest brown rot of Wushan plums was identified and analyzed as Monilinia fructicola, 1-MCP combined with 4 ℃ storage treatment effectively inhibited the incidence of brown rot and the expansion of spot diameter of plums during postharvest storage, and effectively maintained fruit firmness. The study provides a theoretical basis for the occurrence and control of brown rot during post-harvest storage of Wushan plums. [ABSTRACT FROM AUTHOR]

【Objective】According to the climatic characteristics such as the lack of sunshine in Chongqing, combined with the different light demand of different crops and different growth stages, the present study explored the distribution law of the plane light field of the cultivation tank under the conditions of different plant fill light heights and light intensity ratio in the plant factory, and established a quantitative relationship model between the fill light height, light intensity ratio and the plane light field intensity of the cultivation tank, so as to provide support for the automatic, accurate and on-demand regulation of the fill light height and light intensity. 【Method】In the closed intelligent simulation agricultural environment laboratory of Chongqing Academy of Agricultural Sciences, and taking the intelligent LED fill light as the research object, the paper explored the light field intensity change law of the cultivation tank under the conditions of different fill light height and light intensity ratio. The regression support vector machine algorithm was used to construct the spatial light field intensity prediction model of fill light, which took the fill light height, fill light intensity ratio and spatial position information as the input and the plane light field intensity of cultivation tank as the output. Based on this model, the intensity of the plane light field in the cultivation tank was predicted, and the height of the fill light suitable for different crops and different growth stages was adjusted as needed. 【Result】Exploring the law of light field distribution on the plane of cultivation tank under different heights and light intensity ratios, it was found that with the increase of the proportion of light intensity at the same height, the value of light field intensity on the surface of the cultivation tank plane light field also increased; Under the same light intensity ratio, with the increase of fill light height, the light field intensity value in the center area of the plane light field surface of the cultivation tank decreased, while the light field intensity value in the edge area of the light field surface increased to a certain extent. By comparing the five modeling methods, it was found that SVR algorithm had the best performance on the data set. At the same time, the training accuracy R~2 of the plane light field intensity prediction model of the cultivation tank constructed in this study could reach 0.9897, and the testing accuracy R~2 could reach 0.9815, which proved that the model had good reliability. 【Conclusion】 The distribution law of light field intensity in the cultivation tank plane of LED array fill light in plant factory was analyzed, which proved the necessity of building the prediction model of light field intensity in the cultivation trough plane. The precise construction of this model has laid a good support for the optimal dynamic regulation of light source location and intensity in different crops and different growth stages under the conditions of installment agriculture or plant factories. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to study the localization and expression pattern of histone deacetylases（HDACS） family members HDAC3 and HDAC8 in growing follicles of Tan sheep, in order to provide reference for further research on the epigenetics mechanism of follicular development and oocyte maturation regulation in Tan sheep. 【Method】The ovarian tissues of healthy tan sheep were collected and the following growth follicles were mechanically separated: Small antral follicles（diameter 0.5-3.0 mm）, large antral follicles（diameter 3.0-5.0 mm） and preovulatory follicles（diameter>5.0 mm）. The localization and expression of HDAC3 and HDAC8 in different follicles were detected by immunohistochemistry and immunofluorescence respectively. At the same time, the expression of HDAC3 and HDAC8 in the follicles of Tan sheep was detected by Western blotting.【Result】HDAC3 was mainly located in the granular cells of primitive follicles, primary follicles and secondary follicles, granular cells of antral follicles and cumulus cells of Tan sheep, and its expression was up-regulated with follicular development. The localization of HDAC8 in growing follicles was different from that of HDAC3, which was not only distributed in the oocyte and granulosa cytoplasm of primordial follicles, primary follicles and secondary follicles, it was also localized in the cytoplasm of oocytes, granulosa cells and cumulus cells with antral follicles.【Conclusion】These results indicated that the localization and expression of HDAC3 and HDAC8 in growing follicles of Tan sheep were different, suggesting that HDAC3 and HDAC8 may be involved in the regulation of follicular development and oocyte maturation in different ways. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to verify the regional applicability of NDVI-DFI tri-endmember linear mixture model to extract vegetation information in the crisscrossing region of desert oasis in Xinjiang and apply the model to analyze the spatial and temporal variation of vegetation in a gobi region in Xinjiang. 【Method】 Two periods of Landsat8 images in 2008 and 2017 were selected from the desert oasis interlacing zone on the northern slope of Tianshan-Jungaer Basin, Xinjiang, and estimation of fractional cover of photosynthetic vegetatio(fPV), non-photosynthetic vegetation(fNPV) and bare soil(fBS) in the study area based on NDVI-DFI tri-endmember linear mixture model.Verify inversion accuracy with regression analysis.【Result】（i）The spatial location of the pixels identified as pure by the PPI operation and located close to the vertices of the NDVI/DFI triangle was examined by Landsat8 OLI, which meets the application conditions of NDVI-DFI model. However, there were differences in scatter distribution, indicating that some surface elements have changed.（ii） fPV mainly distributed in the southern oasis farmland, fBS mainly distributed in the northern Gobi plain and barren mountains, fNPV mainly distributed in the oasis and gobi interleaved areas and large desert areas. The results of regression analysis showed that there was a significant positive correlation（P<0.01） between the inversion results of NDVI-DFI model and the resampling calculation results of GF-2（high resolution） remote sensing imagery. 【Conclusion】（i） The NDVI-DFI model can be applied to estimate fractional cover of fPV, fBS and fNPV in Northern Slope of Tianshan Mountains-eastern margin of Junggar Basin. The accuracy of inversion results meet the requirements. It has regional applicability for the extraction of vegetation information in the desert oasis ecotone in Xinjiang.（ii） From 2008 to 2017, the level I, III and IV vegetation area in the study area showed a decreasing trend, while the level II and V vegetation coverage increased. The vegetation coverage changed from low to high level, and the high level vegetation increased. The total vegetation restoration area in the study area is greater than the degraded area. [ABSTRACT FROM AUTHOR]

【Objective】The aims of the present paper is to explore the spatial variation and stability of soil aggregates at different soil depths under different years of the deep turning measure. 【Method】The soil of the deep turning measure（2014） was used as a control, and the soil aggregates of 0-20, 20-40, 40-60 cm soil depths were continuously sampled and monitored based on the years of deep turning（2014-2020）. The changes of soil aggregates, particle size distribution patterns and stability of soil aggregates with the age of deep turning were analyzed. 【Result】 WR0.25 was more sensitive to the response to deep turning than DR0.25, which was significantly lower than DR0.25; WR0.25 generally increased with the age of deep turning and decreased with the increase of soil depth; Under deep flipping, WR0.25 was more sensitive to the response of deep turning than DR0.25, and the content of WR0.25 decreased with the increase of soil depth and increased with the increase of deep turning age; MWD showed no obvious overall change with the increase of deep turning age in 0-20 cm soil layer, 20-40 cm soil layer showed a gradual increase trend with the increase of deep turning age, MWD in 40-60 cm soil layer showed an increasing trend with the increase of deep turning age after 1-5 years of deep turning, and MWD gradually decreased after 6-7 years of deep turning. PAD showed a tendency to increase with the increase of soil depth and decrease with the increase of deep turning age. WR0.25, PAD and MWD showed a significant correlation（P<0.05）, in which WR0.25 showed a significant negative correlation with PAD, the correlation coefficient R was-0.750, WR0.25 showed a significant positive correlation with MWD, the correlation coefficient R was 0.866, and the PAD and MWD showed a significant negative correlation relationship, and the correlation coefficient R was-0.795.【Conclusion】The deep turning measure directly acted on the structure of soil aggregates, and the recombination of aggregate content components led to the hierarchical differentiation of the original tillage soil, which was manifested as two-level differentiation of the surface layer and the bottom layer, and the water stability aggregates had greater variation and more sensitive hierarchical response. The deep turning effect makes the soil surface and bottom layer achieve spatial displacement and mixing, resulting in the homogenization of the original layers of each soil layer, and with the increase of the deep turning age, the distribution pattern of soil aggregates tends to gradually converge and the stability gradually increases. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to carry out research on dynamic change characteristics of paddy field and dry land resources in Chongqing, identify the main factors driving the loss of paddy field and dry land resources, analyze the regional differences in the utilization of cultivated land resources, and provide support for improving the utilization rate of cultivated land resources, strengthening the management of provincial agricultural resources, and ensuring regional food security. 【Method】 Based on the interpretation results of historical remote sensing image data, the dynamic change characteristics and spatial differentiation of paddy field and dry land in the two historical stages of Chongqing from 1980 to 2000 and from 2000 to 2018 were quantitatively studied by using geographic gravity center analysis, cultivated land loss rate and other indicators and methods. 【Result】 The study found that areas of paddy field and dry land in each district of Chongqing decreased in the past 40 years. The loss area of paddy field was less than dry land, but the loss rate of paddy field was higher than dry land. The loss of paddy field and dry land both showed a trend from slow scattered occupation to rapid agglomeration occupation over time, and the area gravity center of both cultivated lands had gradually shifted to the northeast, indicating the shift from the western low-altitude area（with high economic growth rate and high-quality cultivated land） to the northeast hilly area（with relatively low economic growth rate and low quality cultivated land）. From 1980 to 2000, the area gravity center shift distances of paddy field and dry land were 0.58,0.97 kilometers, respectively, while that distances from 2000 to 2018 were 2.14,1.57 kilormeters. According to the result of cultivated land loss rate index, paddy field and dry land in most districts belonged to the slow loss type, and the losing rate from 2000 to 2018 was much higher than that from 1980 to 2000. Severely loss regions of paddy field were mainly located in the urban area and suburban areas. The regions of rapid loss were mainly concentrated in the northeast of Chongqing, and the severe and fast loss areas of dry land are concentrated in the urban area. Construction occupation was the primary factor of paddy field loss, and the ecological occupation was the secondary factor. Considering the loss rate of cultivated land resources and the types of cultivated land transformation, the dynamic types of cultivated land resources in paddy field and dry land could be divided into 4 categories, which were construction occupation dominated, ecological occupation dominated, no dominant type, and cultivated land type transformation. Furthermore, 10 subcategories can be identified based on their loss speed. 【Conclusion】There are regional differences in the main characteristics and driving forces of the loss of paddy field and dry land in Chongqing. It is necessary to strengthen the zoning management of paddy field and dry land based on the characteristics of regional cultivated land loss, optimize the ecological and landscape functions of existing cultivated land in the development zone, improve the resource utilization rate and comprehensive production capacity of cultivated land, and ensure food security. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to deeply analyze the influence of the migration and transformation efficiency of available Se in the ‘soil-plant’ system under different forms and compositions, as well as the antagonistic or synergistic effect between Se-Cd.【Method】Through the investigation of crops and soils in the selenium-enriched soil area in Enshi prefecture, the bioavailability of Se in soil was studied by analyzing the correlation between potato Se-Cd content and available Se-Cd in soil. The coupling effect of Se-Cd was revealed from the perspective of effective state of Se and Cd.【Result】The key factor that determined the level of Se in the food chain was the available Se content in soil rather than the total Se content. The level of available Se content determined the level of Se content in potatoes, and Cd in the soil-potato system behaved a similar trend. The bioavailability of Se in soil was closely related to its existing form. The available Se in potato root soil was mainly organic Se and Se4+, and organic Se was most easily absorbed by potatoes. In terms of the Se-Cd coupling effect, as the molar ratio of available Se-Cd in soil increased, the Cd content in potato showed a downward trend, and the increase of available Se content in soil inhibited the potato’s absorption of Cd in soil. There was an antagonistic effect of Se-Cd, and was the strongest when the molar ratio of available Se-Cd in the soil reached 0.199.【Conclusion】The study can provide reference and theoretical basis for local selenium-enriched crops production, and provide evidence for improving the effectiveness of Se in soil, thus improve the added value of agricultural products and realize the efficient development and utilization of Se resources. The antagonistic effect of available Se in the soil on the formation of Cd absorption by plants should be included in the scope of soil environmental quality standard evaluation, so as to form a more scientific and comprehensive new system and new standard for soil environmental quality evaluation. [ABSTRACT FROM AUTHOR]