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【Objective】The present paper aimed to explore the feasibility of reducing the amount of nitrogen fertilizer and a reasonable nitrogen reduction model under late sowing wheat in the Jianghan Plain. 【Method】 Field experiments were conducted with Zhengmai 9023 under traditional and late sowing date with three nitrogen treatments differing in ratios of basal to topdressing. The changes in wheat yield and its constituent factors and nitrogen related indicators were compared across treatments. 【Result】（i） Under the same nitrogen application rate and base-topdressing ratio, grain yield, panicle number and 1000-grain weight were significantly reduced delayed the sowing date. Reduced total dry matter accumulation during flowering and maturity under late sowing was due to the decrease in dry matter accumulation in leaves and stem sheaths; The dry matter accumulation in spike did not show significant change. The changes in dry matter accumulation at maturity were related to leaves, stem+sheaths and grain husk+spike axis. Under the same nitrogen application rate and base-topdressing ratio, the nitrogen accumulation in wheat at flowering and maturity decreased as well; Nitrogen accumulation in flowering leaves of increased under late sowing, but nitrogen accumulation in stem+leaf sheath, ripe leaves and ripe grain husk+spike axis decreased. Under the same nitrogen application rate and base-topdressing ratio, the spike formation rate and nitrogen use efficiency were significantly reduced under late sowing.（ii）Under different nitrogen fertilization treatments and the same sowing date, nitrogen fertilization can be reduced from 180 to 150 kg/hm² under late sowing with insignificant change in yield decreased by 3.33 kg/hm²（M1） and 293.34 kg/hm²（M2） in 2019—2020; 158.67 kg/hm²（M1） and 13.50 kg/hm²（M2） in 2020—2021. The reduction was much lower than that of normal sowing, and the reason was that the number of spikes and grain number per spike were stable when the nitrogen application rate was reduced from 180 to 150 kg/hm², and the 1000-grain weight increased to some extent. Further reducing the amount of nitrogen applied, the yield change under the two sowing dates did not reach a significant level. Under the same base-topdressing ratio, reducing nitrogen application rate, the nitrogen accumulation in the stem+leaf sheath and spike at the flowering stage and grain husk+spike axis were significantly reduced, but dry matter accumulation did not change significantly. Under the same sowing date and base-topdressing ratio, reducing nitrogen application rate, spike formation rate increased significantly, M1 nitrogen utilization efficiency increased significantly, and M2 nitrogen utilization efficiency remained stable. 【Conclusion】Under the conditions of continuous optimization of nitrogen fertilizer management mode, the yield of late sowing wheat under nitrogen reduction treatment was not significantly reduced compared with normal nitrogen yield, but the spike formation rate and nitrogen use efficiency were significantly improved. After a delay of 20 days, the recommended nitrogen fertilizer management model is that the ratio of base to topdressing is m（base fertilizer）∶ m（top dressing before winter）∶ m（top dressing at jointing stage）=1∶1∶1, and the nitrogen application rate can be reduced from the normal nitrogen application rate to 150 kg/hm². [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to the effects of phosphorus application rate on switchgrass growth and soil nutrients in saline-alkali soil, in order to determine the appropriate amount of phosphorus, which provided a theoretical basis for saline-alkali soil improvement and high yield and high efficiency cultivation of switchgrass in Yinbei area of Ningxia.【Method】In Yinbei area of Ningxia, switchgrass, an energy crop, was used as material to study the effects of different treatments on the growth, soil saline-alkali content and nutrient absorption and utilization of switchgrass by setting 0,30 and 90 kg/hm² of phosphorus fertilizer（expressed as P0, P30 and P90, respectively） through field experiments.【Result】At the mature stage of switchgrass, the soil salinity and alkali content in 0-100 cm soil layer of each treatment were all P0>P30>P90, and the soil organic matter, available phosphorus and alkali-hydrolyzable nitrogen contents were all P90>P30>P0. Compared with P0, P90 treatment significantly reduced the soil salinity and alkali content and increased the nutrient content. Phosphorus application contributes to the growth of switchgrass, which promoted the absorption and utilization of nitrogen and phosphorus, and improved the accumulation of aboveground dry matter. Under three phosphorus levels, soil nitrogen balance of payments were deficit, and soil phosphorus balance was surplus only under P90 treatment.【Conclusion】The comprehensive results showed that under the conditions of this experiment, 90 kg/hm² P application rate could not only ensure the good growth of switchgrass and obtain high biomass yield, but also alleviate the saline-alkali pressure, improve the soil nutrient status and maintain a reasonable balance of nitrogen and phosphorus. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to know the composition and distribution characteristics of Erythroneurini leafhoppers in the world, and to explore their world distribution pattern and possible origin and evolution path. 【Method】Based on Dmitriev’s 3 I interactive Keys and Taxonomic Databases, China Knowledge Network, Web of Science and other databases, the relevant literature on the classification of leafhoppers is collected and analyzed, and the species composition and world geographical distribution of Erythroneurini from 1851 to July 2021 was studied according to the geographical distribution data of leafhoppers.【Result】A total of 204 genera and 1929 species of Erythroneurini have been recorded worldwide. The Erythroneurini leafhoppers were distributed in all zoogeographic regions, mainly in the Oriental region, with a total of 133 genera and 857 species, including 98 endemic genera and 765 endemic species, accounting for 48.04% and 39.66% of the total number of the Erythroneurini, respectively. The Afrotropical region took second place, with a total of 51 genera and 293 species, 34 endemic genera and 257 endemic species, accounting for 16.67% and 13.32% of the total number of the Erythroneurini, respectively. The Palaearctic region had 45 genera and 324 species, 12 endemic genera and 230 endemic species, accounting for 5.88% and 11.92% of the total number of Erythroneurini tribe, respectively. The cross-regional distribution of genera and species was dominated by the Oriental-Palaearctic world, with 17 genera and 68 species, accounting for 8.33% and 3.53% of the total number of genera and species, respectively, while the rest regions, except for the Nearctic region, have a lower proportion. The clustering analysis of the geographical distribution of Erythroneurini leafhoppers in the world showed the correlation of the world’s animal geographical divisions, which indicated that the relationship between the Oriental and the Palaearctic, the Oriental and the Afrotropical, the Nearctic and the Neotropical are strong, and the species in these regions communicate frequently. 【Conclusion】A total of 204 genera and 1929 species of Erythroneurini are recorded in the world, which are distributed in various zoogeographical regions, mainly in the Oriental world. The species similarity between the Oriental regions and the Palaearctic regions is the highest, and the interval connection is the closest. [ABSTRACT FROM AUTHOR]

【Objective】This paper studied a rice pest identification method based on Multi-scale Dual-path Attention Capsule Network（MDACapsNet） to provide reference for automatic identification of pests.【Method】Aiming at problems of existing methods had low accuracy in identifying rice pests, a rice pest recognition method based on MDACapsNet was proposed on the basis of capsule network. MDACapsNet consists of encoding module, classification module, and reconstruction module. First, with the addition of a multi-scale dual-path attention block and a local sharing dynamic routing algorithm in the encoding module could enhance the feature extraction capability of the network and reduce the amount of network calculation. Secondly, the loss of reconstructed image was added to the loss function to speed up network training. 【Result】Recognition experiments were carried out on the image database of rice pests under the complex background, with an recognition accuracy rate of 95.31%. Compared with VGG16, CapsNet and ResNet, the recognition accuracy rate of MDACapsNet was improved by 5.47%, 19.83% and 2.83%, respectively. 【Conclusion】The MDACapsNet was effective for the image recognition of rice pest of different sizes, complex backgrounds and diverse postures, indicating that the proposed method can be applied to an automatic detection system for rice pest in the field. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to find an antimicrobial material that could be used to control the disease（rot disease caused by Diploöspora longispora） of morels. 【Method】Triclosan（TCS） was an antimicrobial agent widely used in oral care products and might have an inhibitory effect on the fungal disease of morels. The medium was prepared by adding different concentrations of TCS（0-100 mg/L）, with both sterilized and unsterilized treatments, the effect of TCS on the mycelial growth of Morchella sextelata and the inhibitory effect against undesired microbes in the medium were observed. Then, the sterilized medium with different concentrations of TCS（0-40 mg/L） were inoculated with D. longispora and M. sextelata, and the mycelial growths of the two strains were observed under different TCS concentrations, and the microstructure of D. longispora mycelium, M. sextelata mycelium and D. longispora spores were observed using a light microscopy. A preliminary comparative test of TCS spraying was conducted in the field. 40 mg/L TCS suspension was sprayed directly onto morels with symptoms of rot disease. 【Result】TCS was able to inhibit the growth of undesired microbes on unsterilized media. The mycelial length of D. longispora decreased with the increase of TCS concentration, and the conidia of D. longispora ruptured with contents exudation when the TCS concentration was 40 mg/L. In the preliminary comparative test, one week after the spraying of TCS, the infection range of D. longispora did not expand, and there was no spread of infection. 【Conclusion】 TCS can be tried as an antimicrobial agent for the control of rot disease of Morels at suitable concentrations. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the genetic variation characteristics of main agronomic traits between two Cannabis ecotype hybrid F2 populations planted in different ecological environments.【Method】The F2 population from the hybridization of ‘Yunma 1’ and ‘Dame Blanche’ belonging to different subspecies was used as the research object. Ten agronomic traits（plant height, stem diameter, branch number, etc.） were measured in parents and F2 populations planted under three ecological environments. Genetic variation analysis, correlation analysis and generalized heritability estimation of these agronomic traits were carried out.【Result】Eight agronomic traits showed significant differences under three ecological environments（P<0.05）. The average value of most agronomic traits in F2 generation population was between their parents, but the variation of agronomic traits in F2 generation population was large. In 3 ecological environments, coefficient of variation（CV） of 10 agronomic traits was more than 10%. The average CV（the sum of CV in three ecological environments divided by 3） from high to low was as follows: First branch height > fresh weight > branch length > branch number > plant height > stem diameter > compound leaf width> lobular width >length-width ratio of compound leaf> compound leaf length. There was a close relationship among these 10 agronomic traits. Except for the three traits of lobular width, compound leaf width, length-width ratio of compound leaf（leaf shape）, the other seven agronomic traits showed extremely significantly positive correlation in three ecological environments. The data of plant height, branch number, branch length and other agronomic traits complied normal distribution with typical quantitative traits. The variation range of the generalized heritability of the 10 agronomic traits was 29.508% to 82.575%, and could be arranged as the descending sequence: Branch length > plant height > first branch height > compound leaf length > branch number > stem diameter > compound leaf width >lobular width > fresh weight > length-width ratio of compound leaf. The generalized heritability of plant height and branch length exceeded 80%.【Conclusion】In F2 generation population, the 10 agronomic traits showed significant variation and phenotypic segregation. All these traits were closely related to each other and possessed typical genetic characteristics of quantitative traits. This study preliminarily discussed the genetic variation of main agronomic traits in F2 generation of two Cannabis ecotypes, which can provide a theoretical basis for the selection of varieties with different uses and QTL mapping of related traits. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to identify and analyze the KUP/HAK/KT gene family in sweet potato and provided a theoretical basis for further study on the function of IbHAK gene. 【Method】Based on bioinformatics, the KUP/HAK/KT gene family of sweet potato was identified at the whole genome level by the genome data of Taizhong No.6, and the basic characteristics, phylogenetic evolution, gene replication and expression patterns of family members were further analyzed. 【Result】A total of 22 IbHAK genes were identified in sweet potato. The length of IbHAK protein ranged from 227 aa to 1252 aa, the molecular weight ranged from 18 297.95 to 140 640.46 u, and the isoelectric point ranged from 5.54 to 9.31, all IbHAK genes were located on the plasma membrane, and the complete secondary structure of IbHAK protein had 4 to 13 transmembrane regions. According to the phylogenetic relationship, it could be divided into four evolutionary clusters: Cluster Ⅰ, Cluster Ⅱ, Cluster Ⅲ and Cluster Ⅳ. Chromosome mapping showed that 22 genes were distributed on 11 chromosomes, among which Chr4 chromosome was the most distributed, with 4 IbHAK genes, and 8 replication genes were produced by 22 IbHAK genes. All of the 22 IbHAK genes contained TATA and CAAT elements related to plant growth and development as well as light-responsive elements. All of the IbHAK genes contained at least one stress-responsive element and one hormone-responsive element. IbHAK genes showed tissue expression specificity, among which IbHAK6, IbHAK8, IbHAK9 and IbHAK22 had the highest expression levels in roots, and the expression levels of many IbHAK genes changed under stress. 【Conclusion】Twenty-two KUP/HAK/KT gene family members were identified from the whole genome of sweet potato. IbHAK6, IbHAK8, IbHAK9 and IbHAK22 gene family members were conserved in evolution. Most of IbHAK genes were able to respond to stress. [ABSTRACT FROM AUTHOR]

[Objective] This paper aimed to obtain the optimal combination of soil fertilization under mining area reclamation conditions. [Method] Based on the experimental data analysis of the effects of biochemical composition, biodiversity and maize biological characteristics of reclaimed land in mining area under different fertilization modes, a fuzzy analytic hierarchy process (FAHP) system based on the entropy weight method was constructed to calculate the soil fertilization effect index as the strain variable, and the index as the strain variable, and the regression fitting prediction model with chemical fertilizer coding and biological fertilizer as independent variable was established. [Result] The index of soil reclamation effect of combined application of bio-organic fertilizer and chemical fertilizer was higher than that of single application of chemical fertilizer S and biological fertilizer S. When the amount of chemical fertilizer was 220.15 kg/hm2,the amount of biological fertilizer was 2080.15 kg/hm2 , and the index of soil reclamation effect could reach the maximum value of 0. 9909. [Conclusion] The comprehensive evaluation system and prediction model of soil reclamation effect in mining area proposed in this paper are of high reliability and have certain guiding effect on practical production. [ABSTRACT FROM AUTHOR]

[Objective]This paper aimed to evaluate soil quality objectively and accurately by scientific evaluation methods, which could provide references for preventing soil degradation and improving soil quality in rocky desertification areas. [Method] Taking the rocky desertification area of Hefeng county in Hubei province as the research object, 18 soil attribute indexes of physical, chemical and biological properties of soil were determined comprehensively. The minimum data set of evaluation indexes was determined by principal component analysis and correlation analysis. The weighted values of evaluation indexes were determined by entropy weight method, and the weighted correlation values were calculated by grey correlation analysis method. [Result] According to the ranking of the weighted correlation degree, the order of soil quality in the study area was Xiaping > Zhongying > Swallow > Wuli > Walking Horse. According to the standard table of soil quality evaluation, the grade of soil quality in Xiaping was grade II, Zhongying was grade III, Swallow and Wuli were grade IV , Walking Horse was grade V, and the overall soil quality in the study area was of grade V and consistent with local situation. [Conclusion] The method in this paper can objectively and impartially evaluate soil quality and is simple in calculation and clear in thinking, which provides a new attempt for soil quality evaluation. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to construct the eukaryotic expression of PCDNA3. 1 (-) -bPAGl and express it in Chinese hamster ovary (CHO) cells. [Method] The full-length DNA of bPAGl gene was amplified by PCR and connected with PCDNA3. 1 (-) vector by T4 DNA Ligase. The PCDNA3. 1 (-) -bPAGl expression vector was constructed and transfected into Chinese hamster ovary (CHO) cells. SDS-PAGE and western blotting were performed to detect the expression of the recombinant bPAGl (rbPAGl). [Result] The results showed that the optimized sequence of bPAGl gene about 1218 bp was obtained. After amplification and enzymatic digestion, a 1218 bp fragment and a 5400 bp fragment were obtained from PCDNA3. 1 (-) -bPAGl expression vector. The enzyme digestion and DNA sequencing showed that the DNA sequence of bPAGl gene in PCDNA3. 1 (-) -bPAGl expression vector was consistent with the nucleotide sequence optimized sequence of bPAGl gene. Western-blotting and SDS-PAGE assays indicated that the rbPAGl with the relative molecular weight of about 62 kDa was successfully expressed in CHO cells. The purity of rbPAGl reached above 88% after purification by Ni2+ column chromatography. [Conclusion] In this paper, recombinant bPAGl were successfully expressed by eukaryotic expression systems, which laid a foundation for the further study of antibody preparation and dairy cattle early pregnancy diagnosis. [ABSTRACT FROM AUTHOR]

【Objective】 The study aimed to estimate the harvest loss rate of sweet potato, explore its influencing factors and offer proposes on reducing the loss. 【Method】 This paper measured the loss of sweet potato harvest in Sichuan and Henan, China, using a combination of field survey, questionnaire survey and empirical research. 237 rural households from the Rural Fixed Observation Point of the Ministry of Agriculture were included in the questionnaire survey.【Result】 The loss rate of manual harvest was 2.28 %, the loss rate of mechanical harvest was 4.94 %, and the comprehensive loss rate was 2.97 %, while the manual harvest loss rate estimated by farmers was 4.7 %. At the same time, the results showed that sweet potato varieties, harvesting models, harvesting methods, harvesting time, soil type, farmers’ age, education level, total annual household income, pest level, whether planting in the next season after harvest and whether intercropping, had a great effect on sweet potato harvest losses. 【Conclusion】 Therefore, this paper suggests that farmers should adjust the depth of operation according to different varieties and topography and choose the appropriate type of machine. Besides, the government should promote the knowledge of reducing the loss of sweet potato harvest to farmers. [ABSTRACT FROM AUTHOR]

[Objective] The research has a guiding significance in quantitative management of agricultural soil fertility, land planning management and ecological construction of soil. The comprehensive evaluation method for the soil fertility which has been figured out will provide data support for land grading and quantitative research. [Method]8 fertility indexes (including total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus, available potassium, organic matter and pH value) of the surface soil located at Yujiawu Township, Tongzhou District, Beijing were selected as the indexes for evaluating the soil fertility. Depending on index correlation coefficient method and membership function evaluation method, this paper figured out IFI value (IFI represents the soil fertility), by which soil fertility could be evaluated comprehensively. Then this paper analyzed the trend and space by geostatistical method and GIS technology. [Result]It was found that the variation coefficient of available phosphorus was the biggest, which was 107.04% while the variation coefficient of pH was the lowest, which was 2.80%. The sequence of variation coefficient is: available phosphorus > available potassium > available nitrogen > organic matter > total nitrogen > total phosphorus > total potassium > pH. Under a comprehensive comparison of the index interpolation error with different trends, linear should be selected for rapidly available potassium and IFI while constant should be selected for total nitrogen, available nitrogen and pH value, quadratic should be selected for other indexes. The semi-variance structure was good, which was consistent with the exponential model and Gaussian-type. Therefore, it had spatial correlation. The variation caused by structural factors played a leading role. [Conclusion] According to IFI value, the soil at the research area is divided into 5 levels---excellent soil, good soil, medium quality soil, bad soil and inferior quality soil. The area of good soil, medium quality soil and inferior quality soil accounts for 94.86%. From the special layout, we can know that the fertility of the soil at the research area is evenly distributed; from die north to the south, high fertility area and low fertility area are ribbonlike distributed, whose areas are almost the same. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to explore the adaptability difference of different oat varieties to mild saline-alkali. 【Method】 Taken five different oat varieties as tested materials, the effects of mild saline-alkali on photosynthetic physiology and yield of different oat cultivars at Datan experiment station of Ningxia university in this paper were studied. 【Result】 The net photosynthetic rate and transpiration rate of Mengyan 1 were the highest at the seedling stage, which were significantly higher than that of other treatments（P<0.05）; The CO2 concentration of Baiyan 7 was the highest in the flowering stage, but not significantly higher than that of Mengyan 1（P>0.05）, and the CO2 concentration of Baiyan 7 was 8.17 % and 12.29 % higher than that of Yanke 1 and Baiyan 8;The stomatal conductance was the highest in the mature stage, and 96. 19 % higher than that of Baiyan 8. The POD activity and soluble protein content of Mengyan 1 and Baiyan7 were significantly higher than those of Yanke 1 and Baiyan 8（P<0. 05）. Under mild saline-alkali conditions, the yield of Mengyan 1 was the highest, Baiyan 8 was the lowest. 【Conclusion】 The salinity tolerance of each cultivar was in order of Mengyan 1>Baiyan 7>Bayou 3>Yanke 1>Baiyan 8. [ABSTRACT FROM AUTHOR]

Objective] This paper aims to clarify the genetic diversity of cultivated V. mandarinia in Yunnan province, and to provide a basis for scientific domesticated breeding and bio-control of wasps. [Method] By using the mtDNA COⅠ gene marker, the mtDNA COⅠ gene of 237 domesticated individuals from 8 areas in Yunnan province was sequenced. The genetic diversity, genetic structure and genetic differentiation of the population were then analyzed. [Result] The results showed that a total of 600 bp coding region sequence of the mtDNA COⅠ gene of V. mandarinia was obtained, of which the content of A+T was 68.05%, and apparently showed an obvious AT bias. There were 563 conservative sites and 37 mutative sites, among which the mutation sites accounted for 6.16% of the total analyzed sites. Of 37 mutation sites, there were 30 transformation sites and 7 transposition sites, without insertion or deletion. A total of 12 haplotypes were obtained, of which 6 haplotypes were shared between populations, the rest of haplotypes were not shared between populations. The overall haplotype diversity (Hd) were 0.82958. The mean nucleotide difference (K) was 15.18387, and the nucleotide diversity (Pi) was 0.02526. The genetic distance within each population ranged from 0.00 to 0.0283, and the genetic distance between each population ranged from 0.0001 to 0.0544; there were 50.48% of the mutation originate from inter-population and 49.52% from within population, indicating that the mutation mainly came from outside the population. Fst was 0.50482, the difference was significant (P<0.001）, indicating that there was a greater genetic differentiation between populations. COⅠ gene haplotypes mainly had two clusters, most haplotypes had only one mutation site between them. [Conclusion] The haplotype diversity of the cultured wasp population in Yunnan was high, but the nucleotide diversity was low. The original populations of the cultured V. mandarinia in Yunnan originated from a small number of individuals, and gene exchange was carried out with the local wild populations or introduced populations during the breeding process. There were differences in genetic diversity among the populations. It is recommended that the domesticated populations should use local indigenous sources as much as possible to prevent the introduction of provenances from other places and the gene exchange with wild populations after accidental discharge of domesticated individuals. This would lead to an increase in the genetic diversity of local wild populations, thereby increase the adaptability of wild populations, leading to rapid population expansion. This would help to reduce impact on local biodiversity, especially pollinators. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to analyze the genetic structure and variation of four Channa argus populations and three Albino Channa argus populations from different geographical locations. [Method] The DNA of 350 individuals in all populations was detected by 20 pairs of microsatellite primers. The polymorphism and genetic diversity of all microsatellite markers were analyzed. [Result] All 20 pairs of microsatellite primers detected a total of 356 alleles, the number of alleles (Na）ranged from 4 to 40, with an average of 17.8 alleles per locus. The observed heterozygosity (Ho) was between 0.000 to 0.791, and the mean value was 0.578.The expected heterozygosity (He) ranged from 0.31 to 0.91, with an average value of 0.732.The polymorphic information content (PIC) ranged from 0.271 to 0.901, and the average value was 0.700, the Na, Ho, He, and PIC of all the Channa argus populations were higher than those of the Albino Channa argus populations. The genetic differentiation index(FST) of the seven populations ranged from 0.07 876 to 0.40 303, and the genetic differentiation among all populations reached significant level (P<0.05). We divided four Channa argus populations and three Albino Channa argus populations into two groups by molecular variance analysis (AMOVA）, and found that the genetic variation of these groups was mainly from within individuals, accounting for 69.65% of the total genetic variation. The UPGMA hylogenetic tree showed that the Albino Channa argus and Channa argus were clustered into two independent clades. [Conclusion] In this study, the genetic diversity of four Channa argus populations was higher than three Albino Channa argus populations, the protection of genetic diversity of the three populations should be strengthened to avoid inbreeding. This study provides a theoretical basis for the protection and comprehensive utilization of genetic resources of Channa argus and Albino Channa argus. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to provide a reference basis for the safe production in tobacco fields with medium risk of Cd pollution and remediation, the uptake of Cd by tobacco and its distribution pattern in the whole plant were studied. [Method] The tobacco planting soil with medium risk of Cd pollution was selected for pot experiments to explore the remediation potential of 5 tobacco varieties for Cd in the contaminated soil and safety production about of tobacco. [Result] The concentrations of Cd（1.510-2.110 mg/kg) in 5 tobacco varieties were far less than the limit value of Cd（5.0 mg/kg) in Guizhou tobacco leaves. The order of Cd concentration of 5 tobacco varieties was as follows: Guiyan 8 > Yunyan 87 > CF225 > Nanjiang 3 > Bi’na 1.The Cd concerntration of Guiyan 8 was significantly higher than others. There were no significant difference between Bi’na 1 and Nanjiang 3, and they were significantly lower than others. All of 5 tobacco varieties had strong enrichment ability for Cd（127.695%-204.549%), and the order of enrichment ability was as follows: Bi’na 1>Yunyan 87>CF228>Guiyan 8>Nanjiang 3. The accumulation of Cd in Bi’na 1 had 583.102 μg/plant and the remediation efficiency of Cd in soil was 4.113%, more than 4 other tobacco varieties（2.269%-3.262%). The Cd of Bi’na 1 was mainly stored in the unusable parts such as roots, stems and leaf veins in the tobacco. The distribution rate of Cd in leaves of Bi’na 1 was the lowest with 41.03% concentration, which was lower than that of other tobaccos（above 50%). Bi’na 1 reduced the adverse factors（Cd concentration and distribution rate) in the tobacco production. [Conclusion] Among 5 tobacco varieties, Bi’na maximum accumulation amount of Cd, which mainly exists in unusable part, including root, stalk, leave vein, etc. Compared with other four tobacco varieties, Bi’na 1 reduces the disadvantages during tobacco production. Hence, Bi’na 1 has the potential for safe utilization and restoration of tobacco field medium-polluted by Cd. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to compare the effect of different passivation materials on Bletilla striata on the accumulation of Cd under cadmium stress, so as to provide theoretical support for promote quality of B. striata cultivated in soil polluted by Cd.[Method] A pot-culture experiment was carried out, taking B. striata as test material, using external sources with adding 1.5 mg/kg Cd to simulate heavy Cd contamination of soil, the pH of soil, effective Cd and Cd content in B. striata were analyzed and determined after applying different passivation materials（ 5% silicon-calcium fertilizer, 5% cattle manure organic fertilizer, 5% corn straw biochar, 5% phosphorous-containing substances, 5% silicon-calcium fertilizer+5% corn straw biochar, 5% cattle manure organic fertilizer+5% phosphorous-containing substances+5% silicon-calcium fertilizer+5% cattle manure organic fertilizer). [Result] Among different passivation materials, 5% cattle manure organic fertilizer and 5% corn straws biochar were effective in increasing the biomass in underground stem and whole plant of B. Striata. Compared with CK, the biomass of the underground tubers increased by 62.87% and 59.18%, respectively, and the whole plant biomass increased by 57.36% and 46.07%, respectively. The soil pH treated with cattle manure organic fertilizer+silicon-calcium fertilizer, silicon-calcium fertilizer + corn straw biochar and silicon-calcium fertilizer was higher than that of CK, which increased by 3.84, 3.70 and 3.67 units, respectively. The content of effective Cd in soil treated with silicon-calcium fertilizer, cattle manure organic fertilizer+silicon-calcium fertilizer, silicon-calcium fertilizer+corn straw biochar was lower than that of CK, which decreased by 92.86%, 89.29% and 87.50%, respectively. The content of Cd in root, tuber and leaf of B. striata was the lowest treated with cattle manure organic manure + ilicon-calcium fertilizer, as the decrease rate was 97.60%, 88.80% and 95.29%, respectively. The enrichment capacity of Cd in parts of B. striata were of root > tuber > leaf, and the enrichment capacity of Cd in parts B. striata was the lowest treated with cattle manure organic fertilizer+silicon-calcium fertilizer. [Conclusion] Applying 5% cattle manure organic fertilizer and 5% corn straw biochar have better effect in increasing yield of B. striata tuber. Applying 5% cattle manure organic fertilizer +5% silicon-calcium fertilizer, 5% corn stalk biochar +5% silicon-calcium fertilizer and 5% silicon-calcium fertilizer have better passivation effect on heavy Cd pollution, and applying 5% cattle manure organic fertilizer +5% silicon-calcium fertilizer has best blocking effect on Cd in parts of B. striata. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to take the open-pit coal mining area in southern Karamari mountains as an example, the contents, enrichment characteristics and spatial distribution of heavy metals in typical desert plant Reaummuria soongorica（Rs）and surrounding soil were analyzed. The pollution status of six heavy metals, zinc, copper, chromium, lead, mercury and arsenic (Zn, Cu, Cr, Pb, Hg, As) was evaluated and their sources were explored. [Method] Mathematical statistics and GIS methods were used to analyze the enrichment characteristics and spatial distribution of heavy metals in bipachai, analyze the pollution sources and evaluate the potential ecological risk. [Result] The over-standard rates of Cr, Pb and As in soil samples were more than 70%, and the average values exceeded the background values of Changji. The over-standard rates of Hg in Rs samples were 23.08%. The enrichment coefficient (3.658) of Hg in Rs was much higher than that of other elements, indicating that Rs has a strong tolerance to Hg. Except for Pb, the retention rate of other elements was positive, indicating that there was a certain tolerance in the root of Rs. Zinc and copper mainly came from crustal sources, while other elements were affected by both human and natural factors, especially Hg, which was heavily affected by disturbance in mining area and seriously polluted. Potential ecological hazard assessment results showed that in soil and plant, Zn, Cu, Cr, Pb, As five elements were relatively light pollution, Hg pollution was more serious. The distribution of Cu, Cr and As in Rs was similar, which might come from same sources. The enrichment ability of Rs to As was related to the content of As in soil. [Conclusion] The content of elements exceeding the standard in the soil of the study area was low in Pipa. At the same time, Pipa had a certain tolerance and can be used as a dominant species for ecological restoration. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to provide theoretical basis for rational application of nitrogen fertilizer to wheat, effects of reduced application rates of nitrogen on yield and quality of wheat were analyzed in Yunnan province. [Method] Using a two-factor randomized block design, the newly bred dryland wheat varieties Yunmai 76 and Yunmai 77 were used as materials to set up a nitrogen-use efficiency experiment including 5 N application rates, namely, 300 kg/hm²(N1),240 kg/hm²(N2), 180 kg/hm²(N3) and 120 kg/hm²(N4) and no nitrogen fertilizer(N5), respectively. The related indexes of grain yield, yield components and quality under different rates were determined. The correlation between grain yield and spike number, grain number per spike and 1000-grain weight was analyzed. [Result] Under different nitrogen application rates, the yield of Yunmai 76 and Yunmai 77 decreased with the decrease of nitrogen application rates. When the nitrogen application rate decreased from 300 kg/hm² to 240 kg/hm², the yield decreased by 1.38% and 0.30%, respectively; When the nitrogen application rate decreased to 180 kg/hm²or below 180 kg/hm², the yield was significantly decreased. In terms of yield components, the number of panicles per unit area significantly decreased with the decrease of nitrogen application rate; However, the effect of nitrogen application rate on 1000-grain weight and grain number per spike was not significant. The results of correlation analysis between yield and components showed that there was a extremely significant positive correlation between yield and panicle number(R=0.92）. There was no significant correlation with grain number per spike, but a significant negative correlation with 1000-grain weight. Under the rateof N180 kg/hm² and no nitrogen application, the yield of Yunmai 77 was 10.67% and 28.87% higher than that of Yunmai 76, respectively, and the yield decrease of Yunmai 77 was much lower than that of Yunmai 76 under the same N treatment. In terms of quality, protein content and wet gluten content decreased with the decrease of nitrogen application rates, and the differences were significant; The responses of sedimentation value, stability time and formation time to nitrogen application varied with different varieties. The sedimentation value of Yunmai 76 decreased at first and then increased with the decrease of nitrogen application rate, but the nitrogen reduction rate had no significant effect on the sedimentation value of Yunmai 77. [Conclusion] Yunmai 77 is a wheat variety with tolerant low nitrogen. Considering the yield and quality comprehensively, under the experimental conditions, when the conventional nitrogen application rate in this area is 300 kg/hm², the synergistic improvement of wheat yield and quality can be realized [ABSTRACT FROM AUTHOR]

[ Objective] The present paper aimed to identify the causal agents of Camptotheca acuminata leaf spot, and to test the inhibitory activity of different fungicides against the pathogen, so as to provide scientific evidence for the prevention and treatment of the leaf spot disease of C. acuminata. [ Method] The pathogen of the C. acuminata leaf spot was isolated by conventional tissue isolation method and subjected to pathogenicity test. Combining the morphology observation and rDNA-ITS sequence analysis, the pathogen was identified and the toxicity of 12 fungicides to the pathogen was determined by mycelial growth rate method.[ Result] A fungus was isolated from C. acuminata leaf spot in the Chinese Herb Garden of Guangxi Agricultural Vocational University, and the strain was named as XS-1. After pathogenicity test, morphological observation and molecular identification, it was confirmed that Corynespora cassiicola was the causal agent of the C. acuminate leaf spot, which is reported for the first time in China, and the disease was named as Corynespora leaf spot disease. The results of the inhibitory activity test showed that the selected 12 fungicides had a certain inhibitory effect on the growth of strain XS-1 mycelium. Among them, 20% difenoconazole and prochloraz ME had the strongest inhibitory effect with EC50 of 0.098 mg/L, followed by 20% penconazole EW, 50% carbendazim WP, 20% imazalil EW, 250 g/L propiconazole EC, 10% difenoconazole WG with EC50 of 0.3737, 0.4557, 0.4878, 0.5746 and 0.5956 mg/L, respectively.[ Conclusion] Based on pathogenicity test, morphology observation and rDNA-ITS sequence analysis, the pathogen causing C. acuminata leaf spot is identified as C. cassiicola. 20% difenoconazole and prochloraz ME, 20% penconazole EW, 50% carbendazim WP, 20% imazalil EW, 250 g/L propiconazole EC and 10% difenoconazole WG have strong inhibitory effect on the growth of strain XS-1 mycelium, and can be used as an important reference for the control of Corynespora leaf spot on C. acuminata in the field. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the effects of exogenous amino acid selenium fertilizer on the growth and antioxidant indexes of cucumber seedlings, so as to provide reference for efficient raising and cultivation of high-quality cucumber seedlings.[Method] Using amino acid selenium leaf fertilizer as selenium source and cucumber Guiqing No. 1 as material, different concentrations of amino acid selenium(selenium concentrations were 0,2,4,6,8,10,12 and 14 mg/L respectively)were sprayed on the leaf surface of cucumber seedlings at the stage of one leaf and one heart. To study effects of different concentrations of amino acid selenium on agronomic properties, contents of osmotic regulators and antioxidants, antioxidant enzyme activities and selenium enrichment of cucumber seedlings.[Result] The application of different concentrations of amino acid selenium leaf fertilizer significantly influenced the agronomic properties, contents of osmotic regulators and antioxidants, antioxidant enzyme activity and selenium enrichment of cucumber seedlings(P<0.05, the same as below).With the increase of selenium concentration, the growth indexes of cucumber seedlings increased at that start and then decreased. The plant height, plant width, leaf length, leaf width and root length of cucumber seedlings reached the highest value at selenium concentration of 2 mg/L, and the lower stem length and total chlorophyll content reached the highest value at selenium concentration of 10 and 6 mg/L respectively; The contents of soluble protein, ascorbic acid(AsA)and proline(Pro)in roots, stems and leaves of cucumber seedlings increased at that start and then decreased; The content of malondialdehyde(MDA)in roots, stems and leaves of cucumber seedlings decreased at the start and then increased; When the concentration of selenium was 4 mg/L, the activity of superoxide dismutase(SOD)was significantly increased, while the activities of peroxidase(POD)and catalase(CAT)were the highest at 10-14 mg/L; The total selenium content in roots, stems and leaves of cucumber seedlings increased at the start and then decreased with the increase of exogenous selenium concentration. The order of total selenium content in each organ was: root > stem > leaf.[Conclusion] The maximum selenium concentration that cucumber seedlings can stand is 10 mg/L. In the process of production, low concentration amino acid selenium fertilizer(selenium concentration 6-8 mg/L)can be sprayed to cultivate strong cucumber seedlings. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to provide theoretical basis for studying the molecular mechanism of betacyanin accumulation and improving the nutritional value of Hylocereus polyrhizus, the betacyanin content in fruits, cloned HpCYP76 AD1 gene are detected, and the relationship between gene expression and betacyanin content are analyzed.[Method] The betacyanin content during fruit maturation was measured using the colorimetric method. HpCYP76 AD1 gene was obtained based on fruit transcriptome sequencing data and RT-PCR clone. The physicochemical properties and phylogenetic relationship of protein encoding by HpCYP76 AD1 were analyzed and the gene expression pattern during fruit maturation was detected by qRT-PCR.[Result] The betacyanin accumulated rapidly during fruit ripening, whose content in mature fruit（30 days after pollination） was about 150 times higher than the one 20 days after pollination. The open reading frame of HpCYP76 AD1 gene was 1521 bp, which encoded a protein sequence of 506 amino acids. The relative molecular weight of HpCYP76 AD1 protein was 57.5 kDa and the predicted isoelectric point was 8.86. The HpCYP76 AD1 amino acid sequence had a highest similarity with pear cactus OfCYP76 AD8, which up to 89.96%. HpCYP76 AD1 and Beta vulgaris BvCYP76 AD1, Mirabilis jalapa MjCYP76 AD3 and Amaranthus cruentus belonged to the α class of CYP76 AD1 family, which suggested that HpCYP76 AD1 had a catalytic activity in the two hydroxylation reactions of betacyanin accumulation in fruits. The expression of HpCYP76 AD1 gene was significantly up-regulated during fruit ripening, which was positively correlated with the betacyanin accumulation pattern in fruits.[Conclusion] HpCYP76 AD1 gene from cytochrome P450 family member of H. polyrhizus belonged to the α class, which indicated that it may have a catalytic activity in the two-step hydroxylation reaction of betacyanin accumulation. The expression of HpCYP76 AD1 gene was greatly up-regulated during fruit ripening, which was involved in betacyanin accumulation. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to address the lack of SSR molecular markers in Illicium verum, based on I. verum transcriptome data, EST-SSR molecular markers were developed and the distribution types and characteristics in transcriptome sequences were revealed. The purpose of this study was to lay a foundation for the study of I. verum at molecular level. [Method] SSR loci were screened from I. verum transcriptome data by SSR search program, and the types, quantity and distribution characteristics of SSR repeat motifs were subjected to statistical analyses. An online design software was used to design SSR primers, and the polymorphism result from primers was evaluated by capillary electrophoresis. The genetic relationship between different I. verum germplasm was analyzed by using selected polymorphic primers. [Result] 8210 SSR loci were obtained from 44 267 Unigenes, The proportion of one EST-SSR loci was 11.11%, the proportion of two or more EST-SSR loci was 3.13%, and the proportion of composite SSR loci was 2.09%. The frequency of SSR was 14.24%, with an average of one SSR every 5.37 kb. Dinucleotides and trinucleotides were the main repeat types among the SSR loci, the highest proportion of dinucleotide repeats was AG/CT, which accounted for 46.03%, the highest proportion of trinucleotide repeats was GAA/CTT, which accounted for 16.58%, and the repetition types and proportion of four, five and six nucleotides were relatively low. The number of replicates of the SSR repeat units ranged from 4 to 40 times, and 5 repetitions were the most, accounting for 22.58%, Then there were 6 repetitions, accounting for 19.83%. The length distribution of microsatellites rangeed from 12 to 80 bp, and 12-15 bp was the most, accounting for 37.39%. Sixteen pairs of primers with high polymorphism were screened by amplification of 100 pairs of primers randomly selected. Na was 3 to 8, Ho was 0.13 to 0.88, He was 0.54 to 0.88, Ne was 2.03 to 5.82, I was 0.83 to 1.84. The primer polymorphism information index was 0.43 to 0.81, with an average of 0.63, indicating that the developed EST-SSR loci had higher polymorphism. The genetic relationship indicated that there were different genetic relationships among different I. verum germplasm. [Conclusion] It is feasible to develop EST-SSR markers based on I.verum transcriptome sequences, and its primers have the advantages of high specificity and high polymorphism, the developed SSR markers can provide basis for genetic diversity analysis, functional gene mining, genetic linkage map construction. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to obtain the sequence and structural information of full-length transcripts of taro, and to identify the structural information of genes and transcripts related to starch biosynthesis, so as to provide a scientific basis for the subsequent elucidation of the molecular mechanism of starch biosynthesis and in-depth utilization of taro genetic resources. [Method] The full-length transcripts were sequenced from different tissues (leaves, petioles, corms, stolons and roots) at the age of 3 months using Lipu Taro 1 as the test material. The transcripts were annotated for analyzing their bioinformatics of structural information of AS,APA, lncRNA, TF and SSR sites. Genes and transcripts related to starch biosynthesis were obtained by KEGG annotation and analyzed for AS events and APA. [Result] A total of 38 043 full-length transcript sequences were obtained from three generations of full-length transcriptome sequencing of different tissues of taro. By comparing with the reference genome, 31 058 new transcripts were identified, of which 28 785 were functionally annotated. Structural analysis of the transcripts showed that 9360 AS events, 6436 genes with poly (A) sites, 25 081 SSR loci, 304 lncRNAs, 1911 fusion transcripts and 1608 TFs were identified.14 starch biosynthesis-related genes with 60 transcripts were obtained by KEGG annotation, and their AS events and APA analysis revealed that six genes had AS, containing five types of IR,A5 SS,A3 SS,ES and MEE, and 10 genes had poly (A) sites, of which seven genes had two or more poly (A) sites. [Conclusion] The sequence and structural information of the full-length transcripts of taro are obtained by full-length transcriptome sequencing analysis, and 14 genes and 60 transcripts related to taro starch biosynthesis are identified, which can be used as a scientific basis for the subsequent elucidation of the molecular mechanism of taro starch biosynthesis and in-depth utilization of taro genetic resources. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the polymmphism of IGF2 exon 2 polymorphism with Qinchuan cattle, Simmental cattle, Angus cattle and Xinjiang brown cattle population and its correlation with growth traits, so as to provide basis for genetic improvement of beef cattle. [Method] The polymorphism of IGF2 gene exon 2 was analyzed by PCR-RFLPs in 91 beef cattles of four breeds including Qinchuan cattle, and the association between IGF2 genotype and growth traits was analyzed. [Result ] The polymorphism in exon 2 of IGF2 gene was in Hardy Weinberg equilibrium(P > 0. 05), and belonged to moderate polymorphism(0. 25 0. OS). Correlation analysis between polymorphism of IGF2 gene exon 2 and growth performance of Qinchuan cattle at different months of age showed that body length of AA and AB individuals at 12 months of age was significantly higher than that of BB individuals (P < 0. 05), and there was no significant difference in other months of age (P <0. OS); Chest circumference of AA and AB individuals at 12 and 18 months of age was significantly better than that of BB individuals(P < 0. OS), and there was no significant difference in other index genotypes(P > 0. 05); In all tested varieties, A was the dominant allele. [Conclusion] The results showed that the polymorphism in exon 2 of IGF2 gene had significant correlation with growth performance, which could be used as one of the markers for growth traits assistant selection of beef cattle and provide reference for early selection of excellent beef cattle. [ABSTRACT FROM AUTHOR]

[Objective] The paper aimed to study t he regulatory effect of Lycium barbarum glycopeptide (LbGp) on the immunosuppression induced by cyclophosphamide (CY) in chicks.[Method] 200 of 7 days Highland layers were selected and divided into 5 groups randomly : blank group (NC), cyclophosphamide grou p (CY) and high dose of LbGp (LbGpH), middle (LbGpM) and l ow dose of (LbGpL ) groups. The layers of NC group were received normal saline intramuscularly, the layers of the other 4 groups were injected intramuscularly with 80 mg/ (kg · d ) CY for 3 days to building immunosuppression modeling. After that, the l ayers of LbGpH, LbGpM and LbGpL grou ps were given 10, 5, 2. 5 mg/ (kg · d ) of LbGp respectively for 7 days. On t he 7, 14, 21, and 28 days after the first administration, 5 chicks were randomly sel ected to determine their body weight, spleen index, peripheral bl ood lymphocyte transformation, and spleen histological analysis.[Result] LbGpH significantly increased the body weight of CY-induced immunosuppressive chicks (P < 0. 05 ), the LbGpM significantly increased the body weight of CY-induced immunosuppressive chicks (P < 0. 01 ) ; The LbGpM significantly increased the spleen index of CY-induced immunosuppressive chicks (P < 0. 05); The LbGpH and LbGpM significantly increased the peripheral blood lymphocyte transformation rate of CY-induced immunosuppressive chicks (P < 0. 01); The histological results of the spleen showed that the number of germinal centers in each LbGp group was significantly higher t han t hat in the CY group on t he 14th and 21th day after t he first administration (P < 0. 05) .[Conclusion] L. barbarum glycopeptide has a significant antagonistic effect on the immunosuppression of chicks induced by cyclophosphamide, and the middle dose group has the best effect. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to provide a scientific reference for drought prevention and disaster avoidance of sugarcane production, the temporal and spatial characteristics of sugarcane drought in different growth period in Guangxi were analyzed in recent 60 years. [Method] Firstly the development period of sugarcane, soil data and meteorological data from 1961 to 2020 in Guangxi were collected for the study. Under major concentration for effectiveness of precipitation and dynamic change characteristics of crop coeffi cient, the temporal and spatial variation characteristics of sugarcane drought in growth period were analyzed by linear and periodic analysis method and spatial station technology basing on crop water deficit index. [Result] The interannual drought incidence was the highest in maturity stage, followed by stem elongation stage, and the least in seedling stage and in tillering stage. Light and medium drought are mainly in seedling stage, tillering stage and stem elongation stage. Heavy and extreme drought are mainly in maturity stage. During the study period, there was no obvious linear change trend in the interannual drought incidence at all levels and with a periodic change on the scale of 2 - 5 years. The years of occurrence were mainly in 1970s and 1980s. In terms of spatial distribution, in the seedling stage light drought and medium drought were mainly distributed in the west and south of Guangxi. The occurrence frequency of light drought was less than 40%. The occurrence frequency of medium drought was less than 30 % . The occurrence frequency of heavy drought was less than 10 % and its distribution range was small. In the tillering stage, light drought occurred in all over the region. The occurrence frequency in the southwest of Guangxi was the highest, generally between 21 % and 40%. Medium drought was mainly distributed in the southwest of Guangxi and the occurrence frequency was less than 10% . The occurrence frequency of severe drought was less than 10 % and its distribution range was small. In the stem elongation stage, mild drought was distributed in the whole region with the occurrence frequency between 11 % and 70%. Medium drought was mainly distributed in the northeast of Guangxi with the occurrence frequency between 21 % and 60%. Heavy drought was mainly distributed in the northeast of Guangxi with the occurrence frequency less than 20%. There was no extreme drought in the seedling stage, tillering stage and stem elongation stage during the study period. In the maturity stage, light drought, medium drought, heavy drought and extreme drought were distributed in whole study region. The occurrence frequency of light drought was less than 30%. The occurrence frequency of medium drought and severe drought were less than 40%. The occurrence frequency of extreme drought was the most and its distribution was wide. The regions with high extreme drought occurrence frequency were mainly distributed in the center, south and east of Guangxi with the occurrence frequency between 31 % and 50%. [Conclusion] The light and medium drought are the main drought in the seedling stage, tillering stage and stem elongation stage of sugarcane in Guangxi during the sugarcane development. The heavy and extreme drought is the main drought in the maturity stage. In the maturity stage of sugarcane, the heavy and extreme drought occur once every 2 - 3 years in the center, south and east of Guangxi. The regions above should be get more attention for drought prevention and disaster avoidance. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the effects of water and nitrogen coupling on the growth characteristics of edible canna and soil environment, so as to provide reference basis for high-yield and high-efficiency cultivation and sustainable development of industry of edible canna. [Method] Edible canna variety Guixingyu 3 was planted in a canopy. Four irrigation water quantities [( 20 ± 5 )% ( Wl), ( 40 ± 5)% ( W2), ( 60 ± 5)% ( W3)and ( 80 ± 5)% ( W4)J of field capacity J and four nitrogen application rates [pure nitrogen application of O kg/hm² (NO),300 kg/hm² (Nl),600 kg/hm² ( N2 )and 900 kg/hm2 (N3)J were designed. A total of 16 water nitrogen coupling treatments were used with Wl NO as control ( CK). The soil enzyme activity, soil physical and chemical properties, agronomic properties, leaf physiological characteristics and tuber yield of edible canna were measured and analyzed. [Result] With the increase of irrigation, soil porosity, alkali hydrolyzable nitrogen content, dehydrogenase activity, sucrase activity, stem diameter, starch content and tuber yield increased first and then decreased. Under the condition of nitrogen deficiency, the content of available phosphorus, available potassium, phosphatase activity, tiller number and plant height of edible canna increased gradually with the increase of irrigation. With the increase of nitrogen application, the soil porosity, sucrase activity, plant height and stem diameter of edible canna increased first and then decreased. Under low water condition, soil alkali hydrolyzable nitrogen content, available phosphorus content, available potassium content, urease activity, tiller number and tuber yield of edible canna increased gradually with the increase of nitrogen application. Compared with CK, the tuber yield of edible canna under each water and nitrogen coupling treatment increased by 7 . 78 % - 70. 28 %, and the yield of W3 N2 was the highest. The results of variance analysis showed that the coupling effect of water and nitrogen had a significant (P < 0. 05)or extremely significant (P < 0. 01) effect on alkali hydrolyzable nitrogen content, available phosphorus content, enzyme activity, tiller number, plant height and starch content, but had no significant effect on soil porosity, available potassium content, stem diameter, soluble sugar content and soluble protein content (P > 0. 05 ). [Conclusion] The water nitrogen coupling model with field water capacity of (60 ± 5 )% and nitrogen application rate of 600 kg!hm2 has a better comprehensive effect on the improvement of soil environment and the growth of edible canna, which is suitable for popularization and application in edible canna planting area. [ABSTRACT FROM AUTHOR]

[Objective]The present paper aimed to understand the cold tolerance of sugarcane main parents and the change characteristics of cold tolerance evaluation related traits, and to provide reference for breeding cold tolerance sugarcane varieties and reducing the harm of frost to sugarcane production. [Method] A total of 102 parents were selected for natural frost test in 5 crops consisted of two plant cane( 2017P and 2019P) and 3-year ratoon crops(2018F, 2019S and 2020F) during 2017-2020 in Zizhong, Sichuan, a frost prone area. The correlation analysis, variance analysis, calculation of broad sense heritability and cluster classification were processed. [Result] It was found that there were differences in the types and degree of cold damaged traits among parents under low temperature environments, and ratoon cane was more vulnerable than plant cane. The damaged traits were significantly ( P < 0. 05 ) correlated with some agronomic characters under cold or light frost. The performance of damaged traits was affected by parent, year and their interaction. The damage rate of plant was a high heritability trait, which can be used to evaluate cold tolerance under cold and light frost. The damage rate of stalk length and internode were medium heritability traits, which were less affected by low temperature environments, and can be used to evaluate cold tolerance, and the damage rate of internode was slightly better than that of stalk length. The percentage of green leaves varies greatly among years, which can be used for cold tolerance evaluation under light or moderate frost. The percentage of parental variance decreased, and the heritability also decreased when combined data from different trials were used for variance analysis. Cluster classification showed that trials plant crops in 2017 and 2019 were not suitable for the evaluation of cold tolerance of parents. Among the tested parents, 58. 89% of the parents were identified as good or better cold tolerance and 23. 53 % as poor or poorer.[Conclusion] There are differences in the types and degree of cold damaged traits among parents under low temperature environments, and the cold tolerance of sugarcane belongs to medium to high heritability. The traits that can be used for cold tolerance evaluation are affected by the degree of low temperature. Mild and severe low temperature stress should be set for indoor cold tolerance test. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to the problems of shallow soil arable layer depth, soil salinization and reducing maize yield in maize fields in Ningxia Yinbei irrigation area, the effe cts of different Fenlong tillage depths on soil available nutrients and maize yield were studied to select suitable Ningxia silver the Fenlong tillage technology in the north yellow irrigation area realizes the benign production of the soil. [Method] This experiment adopted a randomized block design, with Fenlong tillage depth 40 cm ( FIAO: Tillage depth 0 - 40 cm), Fenlong tillage depth 50 cm ( FISO: Tillage depth 0 - 60 cm) and traditional rotary tillage ( CK: Tillage depth 0 - 20 cm) as a control. Soil samples were collected at different growth stages of maize to determine soil water content, pH, available nitrogen, available phosphorus, available potassium and organic matter content and maize yield under different F enlong tillage treatments variety. [ Result] The soil water content of different Fenlong tillage treatments was significantly different in different growth periods of maize compared with traditional tillage. From the emergence period to the milking period, FIAO was significantly higher than that of CK, and the highest soil water content of FIAO was 16. 99%, followed by FISO, the soil water content was 16. 86%, which was 6. 5% and 5. 8% higher than that of CK, respectively; FIAO and FISO could significantly reduce the soil pH; FIAO and FISO in the maize jointing and tasseling period had significantly higher soil available nitrogen content than that of CK, espec ially FIAO, the soil available nitrogen content increased significantly after Fenlong tillage treatment; The average content of soil available phosphorus in FIAO and Fl.SO during the entire growth period was higher than that of CK, especially Fl.SO was the most significant after Fenlong tillage treatment, and t he content of soil available phosphorus was also significantly increased after Fenlong tillage treatment ; FIAO had significantly higher soil available potassium content t han that of CK in the early period of maize growth, FIAO could effectively increase the soil available potassium content; FIAO and Fl.SO had significant soil organic matter content in both the emergence period and jointing and tasseling period higher than that of CK, and the soil organic matter content after Fenlong tillage treatment significantly increased; Among the yield components of maize kernels, FIAO and Fl.SO had a greater effects on the hundred-kernel weight, number of kernels per ear, number of ears per 6fJ7 m2 and yield of maize kernels CK increased significantly, with FIAO being the most significant, which increased by 48. 22 % compared with traditional tillage. The yield of maize was significantly positively correlated with the content of available nitrogen and available potassium in t he soil. [Conclusion] Fenlong tillage can effectively reduce soil pH and increase soil water content, thereby increasing soil available nutrient and organic matter content, also, the content of available nitrogen and available potassium in the soil are the main factors affecting maize yield and ultimately increase maize yield. Therefore, it is believed that Fenlong tillage can be used as a new agronomic measure for the saline l and of N ingxia Yinbei irrigation area. [ABSTRACT FROM AUTHOR]

[Obj ective] The present paper aimed to study genetic variation of flower and leaf traits of flax, and to provide basis for germplasm innovation of flax. [Method] Genome-wide association analysis was used to detect SNP sites and candidate genes that were significantly associated with related traits in flax flowers and leaves. [Result] Among the 269 flax materials tested, the most ( 56. 50%) of petals were blue. The most corolla shape was pentagonal ( 42. 75%) . Most of the anthers were blue (86. 61 % ) . The most common leaf color was dark green (58. 73%) . Most of the leaves were lanceolate ( 56. 87%) . Genome-wide association analysis revealed 3 SNP and 8 candidate genes that were significantly associated with flax color. Lusl 0033621 ( pectinesterase) and Lusl 0007409 ( 13-galactoside) genes were involved in the regulation of flax color formation . There were 3 SNP loci significantly associated with corolla shape and 6 candidate genes, among which Lusl0000554 ( leucine-rich PPR motif) gene was closely related to corolla development. One SNP locus was found to be significantly associated with anther color of flax, and five candidate genes were identified. Lusl0010403 ( anthocyanin reductase) gene was directly involved in anthocyanin metabolism. One SNP locus and four candidate genes were detected, among which Lusl0005600 ( PPR motif protein rich in leucine) was involved in regulating leaf color formation. Three SNP loci significantly associated with leaf shape were detected, and five candidate genes were identified, among which Lusl 0033007 gene was involved in regulating the formation of leaf internal structure. [ Conclusion] Flax flowers and anthers are mainly blue. Genome-wide association analysis can detect key candidate genes for association between flowers and leaves. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to look for a new way for collecting germplasm resources of wheat resistant to pre-harvest sprouting ( PHS). [Method ] The I, II and Ill batches of the seedlings of wheat grain left in the field from July 1 to July 31, August 1 to August 31 and September 1 to October 10 were collected, which were transplanted into observation nursery and in the middle of October, respectively.[Result] Through the observation of growth consistency, it was found that 93 % of the seedlings of wheat grain left in field in the I batch had the same direct agronomic traits as the wheat varieties planted in the previous crop, while the direct agronomic traits in the II and Ill batches were different. It was found that 94. 1 % of the I batch of the seedling of wheat grain left in the field were susceptible to sprouting, and only 3 . 6% and 2 . 3 % of the seedlings were moderately resistant and resistant, all of the II and Ill batches of the seedling of wheat grain left in the field showed higher resistance to PHS than the middle level, and the later the collection batch was, the higher the proportion of high resistance PHS single ear was; Through the analysis of growth environment factors of wheat seedling with resistance to PHS, then artificial distant hybridization was carried out, it was found that the seed setting rate of artificial distant hybridization between Aegilops tauschii Coss grown in the same field as the wheat seedlings and common wheat was 5 %, which fully proved the possibility of natural cross between A. tauschii and Triticum aestivum in the field; Detecting and analyzing the genomic DNA of ten wheat seedlings with the highest resistance to PHS, A. tauschii Coss, wheat varieties which were mainly cultivated near 10 years in the same field, the primers Xgdm33 and Xgwm52 not only detected a large number of DNA fragments from A. tauschii Coss, but also detected DNA fragments homologous to the previously planted wheat varieties, it was proved that the seedling of wheat grain left in the field was the offspring of natural hybridization between A. tauschii Coss growing in the field and previously planted wheat. [Conclusion] Using the method collecting the seedling of wheat grain left in the field, the wheat germ plasm resources with high resistance to PHSit could be obtained. [ABSTRACT FROM AUTHOR]

【Objective】 The paper aimed to explore the effect of tobacco-garlic rotation on soil fungal community structure in tobacco fields, in order to find an agronomic management model to improve soil health. 【Method】 Using High throughput sequencing technology to detect soil fungi of tobacco garlic crop rotation in susceptible tobacco field and healthy tobacco field, the effects of tobacco garlic crop rotation on soil fungal community structure were analyzed. 【Result】The results showed that the predominant fungi at phylum were Ascomycota, Basidiomycota and norank＿ k＿＿Fungi, accounting for 90.80%-94.59% of the total fungi in the experimental tobacco field in Dec hang county. Before the tobacco transplanted, the relative abundance of Ascomycota and Basidiomycota in susceptible tobacco field growing garlic was higher than that in healthy tobacco fields; Compared with healthy tobacco fields, the relative abundance of Eurotiomycetes was significantly decreased and Sordariomycetes was significantly increased in susceptible tobacco fields; norank＿o＿＿Sordariales and Fusarium in susceptible tobacco field growing garlic were significantly higher than those in healthy tobacco fields, but Fusarium was significantly lower than that in the susceptible tobacco field growing tobacco. The unclassified ＿f＿＿Trichocomaceae was lower than that in healthy tobacco field. At the maturity stage and before transplantation, the relative abundance of Basidiomycota was higher remarkably in susceptible tobacco field, which was significantly positive correlation with organic matter and alkaline nitrogen. The fungal diversity at vigorous growing stage in healthy tobacco field was significantly lower than that before transplanting, but was slightly higher than that in susceptible tobacco field at the same stage, and then enhanced significantly in maturity stage. The diversity of fungi in susceptible tobacco field before transplanting was the highest. 【Conclusion】 The garlic planting improved the species and diversity of beneficial fungi in susceptible tobacco fields, and reduced the relative abundance of pathogenic bacteria, which reduced the incidence from 50.15% to 8.57%. Therefore, the tobacco garlic crop rotation could change the soil fungal community structure and make it tend to healthy tobacco field, thus reducing the occurrence of fungal soil-borne diseases in tobacco field [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to confirm the bacterial community composition and diversity of healthy and root rot strawberry in rhizosphere soil, non-rhizosphere soil and root tissue. 【Method】 The V3-V4 region of the bacterial 16 S r RNA gene in rhizosphere soil, non-rhizosphere soil and root tissue was amplified, the amplified fragments were sequenced by Illumina MiSeq high-throughput sequencing technology, and their bacterial community composition and diversity were analyzed. 【Result】 The microbial diversity was rich in the soils and root tissue of strawberry. Healthy and root rot strawberry group samples got 30 phyla, 78 classes, 131 orders, 238 families, 489 genera and 30 phyla, 78 classes, 131 orders, 233 families, 483 genera, respectively. At the phylum level, Proteobacteria, Bacteroidetes, Actinobacteria and Acidbacteria were the dominant phyla in all rhizosphere and non-rhizosphere soil. The relative abundance of Actinobacteria and Bacteroidetes in rhizosphere and non-rhizosphere soil was different from that of healthy and root rot strawberry. Proteobacteria and Cyanobacteria were the dominant phyla in all root tissue. The relative abundance of Proteobacteria and Cyanobacteria in root tissue was significantly different from that of healthy and root rot strawberry. At the genus level, the dominant genera in all rhizosphere and non-rhizosphere soil were Sphingomonas, Novo sphingobium, Burkholderia, Streptomyces, Gemmatimonas and Bacillus. The relative abundance of dominant genera was significantly different between healthy and diseased groups. The dominant genus in all root tissue was Streptophyta, which relative abundance in root tissue was significantly different from that of healthy and diseased groups. The analysis of samples comparison showed that the difference of bacterial community structure in root tissue was greater than that of rhizosphere and non-rhizosphere soil. 【Conclusion】 Bacterial richness and diversity in the rhizosphere soil and root tissue increased, of which in the non-rhizosphere soil downed after root rot infection. There were significant differences in bacterial community composition of rhizosphere soil, non-rhizosphere soil and root tissue from healthy and root rot strawberry. Among them, Streptophyta, Streptomyces, Burkholderia, Gemmatimonas and Bacillus might be the key bacteria for preventing strawberry root rot. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to know the below-ground ectomycorrhizal status of Castanea mollisima in the major producing area （Luotian county） of Chinese chestnut. The EMF community composition, morphological and molecular identification of C. mollissima were investigated in representative ≥80-year-old chestnut orchards in Luotian. 【Method】300 root samples of C. mollisima were collected and a total of 55 ECM morphotypes were obtained based on morphological characters.【Result】The top50 OTUs were assigned to 34 genera, 15 unclassified species and other taxa. The top 20 taxa in abundance accounted for 95.99% of the top50 OTUs, which were belonged to Basidiomycota （account for 60%, contained five dominant genera: Lactarius, Guehomyces, Inocybe, Russula and unclassified＿ Thelephoraceae）, Ascomycota（30%）, Mortierellomycota（5%）, and other（5%） were belonged to unclassified fungi. Furthermore, among the 22 EMF identified, genus Trichoderma had the largest variety of strains（6）, followed by Fusarium（4）, Penicillium（3）, Talaromyces（3）, Pestalotiopsis（2）, and other three genera: Ilyonectria, Castanediella, and Leptodontidium each possessed 1 specie. Of these fungi, 11 strains sharing high homology with strains which belonged to Fusarium, Trichoderma, Talaromyces and Penicillium were reported with biocontrol function previously, which indicated the 11 strains isolated might also have the potential of biological control. 【Conclusion】 This was the first study to characterize the ECM communities in major producing area of Chinese chestnut, which would lay a foundation for improving chestnut resistance by ectomycorrhizal fungi. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to study the effects of Pandanus amaryllifolius Roxb. intercropping with Areca catechu L. on the structure and diversity of soil bacterial communities, to clarify the key environmental factors affecting soil bacterial community in the intercropping mode, so as to provide a theoretical basis for optimizing the betel nut intercropping mode and the development of tropical farmland economy. 【Method】 Through the method of field experiment, the experimental plots including A. catechu monocropping （control'), P. amaryllifolius monocropping （control） and P. amaryllifolius intercropping with A. catechu were established in Xinglong area to measure soil physical and chemical properties, nutrient content, soil bacterial abundance, and diversity to explore the effect of intercropping model on soil bacterial community structure and diversity. 【Result】 The results showed that the ACE index, Chao1 index and Shannon index of the bacterial community under the A. catechu intercropping P. amaryllifolius model were significantly reduced than control（P<0.05,the same as below）. In intercropping mode, pH, electrical conductivity, total phosphorus, and bulk density were the main environmental factors that affected the changes of soil bacterial communities. In the three planting modes, the dominant bacteria phyla of bacteria were Proteobacteria, Actin bacteria, Actin bacteria, and Chloroflexi. The relative abundance of Proteobacteria, Acid bacteria and Acidobacteria was decreased, and the relative abundance of Chloroflexi was increased. Among them, Acid bacteria was significantly positively correlated with soil bulk density; Chloroflexi was extremely significantly positively correlated with conductivity and organic matter （P<0.01,the same as below）, extremely significantly negatively correlated with total phosphorus, and significantly negatively correlated with total potassium. 【Conclusion】 P. amaryllifolius intercropping with A. catechu does not affect the total number of bacterial OTU, but significantly reduces the diversity index of soil bacterial community by reducing pH and increasing electrical conductivity. Intercropping mode reduces the contents of total phosphorus, total potassium and organic matter by increasing soil bulk density, while reducing the abundance of Proteobacteria, Actinomycetes and Acid bacteria, but increasing the abundance of Chloroflexi. It can be seen that although the betel nut intercropping system significantly reduces the content of soil nutrients, it can improve the abundance and diversity of in-situ soil bacterial flora of betel nut forest, which is of positive significance to maintain the soil health of betel nut forest and promote the development of related industries of betel nut and betel nut. [ABSTRACT FROM AUTHOR]

【Objective】 The composition of microbial community in rhizosphere soil of Juncao ‘Oasis No.1’ was further studied in order to screen out dominant strains with important ecological value in rhizosphere soil. 【Method】 Soil samples were taken from saline and alkaline lands with and without Juncao ‘Oasis No.1’, and microbial populations were sequenced using 16 s DNA high-throughput sequencing to identify the differences between the two microbial populations, so as to screen out the dominant strains in rhizosphere soil of Juncao ‘Oasis No.1’. The dominant bacteria with important ecological value were isolated, cultured and identified by Colony PCR. 【Result】 The abundance of soil microbial population in the experimental lot was much higher than that in the blank lot, and the composition of soil microbial population in the experimental lot also changed significantly compared with that in the blank lot, the abundance of ecologically important bacteria in the rhizosphere soil of Juncao ‘Oasis No.1’ was significantly increased .After isolation and culture, Colony PCR identification showed that the dominant strains were successfully isolated and cultured, which were Acidobacteria and Sphingomonas.【Conclusion】 In this paper, the dominant strains with important ecological value in rhizosphere soil of Juncao ‘Oasis No.1’ were screened and cultivated, which provided theoretical basis for the improvement of salt-alkali soil by Juncao ‘Oasis No.1’ and had important guiding significance. [ABSTRACT FROM AUTHOR]

【Objective】 The changes characteristics of microenvironment in different bagging time and fruit quality of early-maturing pear were analyzed. 【Method】 ‘Sucui 1’ pear cultivar was used as material for studying characteristics of temperature and humidity in different bagging time after flowering. 【Result】 (i) Daily mean temperature and humidity showed an upward trend at early-maturing pear in the growing periods of pear fruits; The diurnal variations of different bagging time in two stands showed a single peak curve at a day from 0:00 to 24:00, which had peak values from 14:00 to 15:00, while the lowest at about 4:00 to 5:00; The diurnal variation of humidity declined with temperature increasing, which performed reserved trend compared with the diurnal variation of temperature. However, humidity presents the ‘V’ curve. The humidity range value has large discrepancy by different treatments. (ii) The range of temperature and humidity with different bagging time treatments on early-maturing pear ‘Sucui’ showed inconsistencies, which formed different microenvironment. The effects on fruit quality of early-maturing pear were different by different treatments. In details, the Pericarp glabrousness and the skin brightness(L) were obviously improved in T1, which were all in sequence of T1> T2> T3, The nutrients content(sucrose, glucose, fructose, SSC, sugar acid ratio) of fruit in HT1 treament were significantly higher than FT1 treatment. (iii) The effects of different treatments on fruit size, single fruit weight and pericarp firmness were not significant. 【Conclusion】 The bagging of early ripening pear is better than 35 days after flowering stage, and the quality of yellow pear white paper bag is better than that of compound double light paper bag. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to construct soil salinity prediction model in arid region based on field investigation data and then used fuzzy neural network method to conduct surface soil salinity prediction simulation. 【Method】 Firstly, the paper selected seven soil salinization influencing factors according to actual situation in study region and extracts information needed, followed by getting the relation between soil salinity and influencing factors via gray correlation analysis method. Also, taking influencing factors as input sample and soil salinity as output factor, the effective T-S fuzzy neural network model was established for predicting soil salinity. 【Result】 The average relative error was 13.092%, the minimum error 0.875% and the maximum relative error was 41.733%, with higher prediction precision compared. 【Conclusion】 The result presumed that T-S fuzzy neural network model enjoyed a good prediction effect and could be used to predict the soil salinization so as to provide an effective way to predict the change laws of soil salinization in arid regions. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to explore the nutrient utilization and yield characteristics of mechanical direct-sowing indica hybrid rice. 【Method】 Taken fifteen different indica hybrid rice cultivars as tested materials, the effects of mechanical direct-sowing under different N fertilizers levels on the absorption,translocation and utilization of N, phosphorus(P), potassium(K) and yield of indica hybrid rice during filling stage were studied, meanwhile the correlations of nutrient utilization characteristics with grain yield and N utilization efficiency(NUE) were explored. 【Result】 According to cluster analysis of yield, under mechanical direct-sowing, N fertilization treatment and three yield classification types had an obviously significant effect on the accumulation and translocation of N, P, K during filling stages and grain yield. There existed significantly positive correlations between the amounts of N, P and K translocation in leaves and stem-sheath under different yield types, which could promote nutrient translocation during filling stage and increase grain yield; However, the correlation coefficient of P and N, P and K significantly decreased in translocation conversion rate of P from heading to maturity stage, which could not significantly improve NUE. Under mechanical direct-sowing in different yield classification types, the various indicators on yield and nutrient utilization characteristics of N fertilization treatment were significantly higher than those of no N treatment. F you 498, Dexiang4103 and Chuanjiangyou 527 were high-yielding and high NUE indica hybrid rice cultivars, being the best cultivars in this paper referred as the mechanical direct-sowing condition. Compared with medium and low yield types, mechanical direct-seeding high-yielding cultivars promoted the accumulations of N, P and K at the heading and maturity stage, increased nutrient translocation in leaf and stem-sheath during filling stage, especially significantly enhanced the translocation amount of N and K in leaves and translocation amount of K in stem-sheath, further facilitated the translocation conversion rate of K in different vegetative organ, played the coupling effect of absorption and utilization of N and K and then promoted yield, which was the important characteristic of high-yielding indica hybrid rice under mechanical direct-seeding; The results also showed that on the premise of effective panicle number, high grain number per panicle and seed setting rate of high yield types, more than those of low yield cultivars, which was another important reason for high-yielding indica hybrid rice cultivars further to increase yield under mechanical direct-seeding. Correlation analysis indicated that there existed significantly positive correlations of the translocation amount of N and K in leaves and stem-sheath and the translocation conversion rate of K during filling stage with NUE, furthermore, the translocation amount and translocation conversion rate of K had high significant effects on grain yield and NUE under mechanical direct-seeding condition. 【Conclusion】 Compared hybrid indica rice varieties with the middle class and low-yield type, high-yielding varieties can significantly improve leaf nitrogen and potassium transfer volume, as well as the potassium transfer volume of the stem and then significantly improve the contribution rate of potassium transport in the strong period, which is significant for the production of hybrid indica rice and the utilization rate of nitrogen fertilizer in the coordinated increase of the live transmission, which is the main physiological characteristics of the high-yielding varieties of the hybrid indica rice. At the same time, under the premise of ensuring sufficient amount of effective ear( 200 × 104/hm2), higher per ear grain number( 173. 0 granule) and the yield rate( 89. 5 %) are another important characteristics of the high-yielding variety of hybrid indica rice. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aims to explore the dynamic changes of the chemical composition of K326 and Hongda of flue-cured tobacco in different ageing habitats under different producing areas. [Method]The effects of total sugar, reducing sugar, total nitrogen, nicotine, potassium, chlorine, sugar/nitrogen, potassium/chlorine, total amount of incense, volatile organic acids, polyphenols changes were studied in the K326 and Honda flue-cured tobacco under different storage location and producing areas. [Result]Total sugar and nicotine content were the main differences between K326 and Hongda eultivars. The total sugar content of Hongda varieties was higher than that of K326 and the nicotine content of K326 was higher than that of Hongda. For producing area, the tobacco from Honghe had the lowest total sugar content and the highest nicotine content. The tobacco from Kunming had the highest total sugar content and low nicotine content, The tobacco from Qujing had the lowest nicotine content and the highest organic acids and polyphenols, flic content of total amount of incense increased with the prolongation of ageing period, file content of volatile organic acids and polyphenol oxides decreased with the prolongation of aging time. The correlation analysis showed that there was significant positive correlation between total amount of incense and nitrogen content (R2 = 0. 37) , volatile organic acids and chlorine content had the positive correlation ( R2 = 0. 55) and there were negative correlation with potassium and total amount of incense. The content of polyphenol compounds was positively correlated with total sugar, potassium, chlorine, sugar/nicoline, nitrogen/nicotine and volatile organic acids, and the content of polyphenol compounds had negative correlation with reducing sugar, total nitrogen, potassium/chlorine, and total amount of incense. [Conclusion] In the process of natural aging, flue-cured tobacco cultivars and the tobacco producing areas have significant effects on the chemical composition of tobacco leaves. This paper explores the differences in the chemical composition of the Honghe, Kunming, Qujing and K326 and Hongda cultivars. [ABSTRACT FROM AUTHOR]

[Objective] The objective of the present paper is to explore the enzyme activities changes of K326 and Hongda of flue-cured tobacco in different aging locations under different producing areas. [Method]The enzyme activities of protease, amylase, peroxidase, and polyphenol oxidase were studied in tin; K326 and Honda flue-cured tobacco under different storage locations and producing areas. [Result] Different ecological conditions warehouse had different humidity and temperature, including that Yuanjiang was with high temperature and high humidity warehouse, Milei was with moderate temperature and high humidity warehouse, Chuxiong was with moderate temperature and moderate humidity warehouse, and Qujing was with low temperature and low humidity warehouse; The four enzyme activities of two flue-cured tobacco eultivars had significant differences. The activities of protease, amylase, polyphenol oxidase and peroxidase in K326 cultivars were significantly higher than those in Hongda eultivars, and tin; fluctuations were also great. The dynamic changes of protease and polyphenol oxidase activities of K326 and Hongda eultivars in three storage sites were basically the same, and the dynamic changes of amylase and peroxidase were different. There was a significant negative correlation between protease and peroxidase (n = -0. 217) , and there was a significant positive correlation between polyphenol oxidase and amylase (R2 = 0.226). [Conclusion]In tin; course of natural aging, storage locations, flue-cured tobacco eultivars, sampling batches were tin; factors that resulted in the complicated changes of the activities of protease, amylase, polyphenol oxidase and peroxidase. In the present paper, tin; dynamic changes of the four enzymes in natural aging were explored, and it was clear that tin; change of enzyme activity was the reason that Hongda cultivar had more storage resistance than K326 cultivar. [ABSTRACT FROM AUTHOR]

[Objective] The present paper explored the spatial distribution pattern and driving factors of aquaculture in Sichuan province, which aimed to provide reference for optimizing the layout of aquaculture and then promoting the quality and product of this industry. [Method] Taking the country (municipal district) of Sichuan province as the basic spatial research unit, with the help of the province' s fishery statistical yearbook and local one, the spatial distribution pattern, influencing facotrs and spatial heterogeneity of domaint factors of aquaculture in Sichuan province were analyzed by using the spatial autocorrelation analysis method (Moran' s I), the geo-detercor and the geographically weighted regression (GWR) model respectively. [Result] The results showed that both aquaculture area and product were characterised by a significantby positive spatial correlation and the plain and hilly areas along the Minjiang and Tuojiang Rivers in eastern Sichuan (including Rong county, Weiyuan county, Zizhong county, Jingyan county, Renshou county, Yanjiang district, Jianyang city, etc.) were the province' s primary aquaculture cluster; the aquaculture area, average yield level, the number of freshwater fish fry and aquaculture labor force were main influencing factors of aquaculture product in Sichuan province ; In the positive regression coefficient effect of domain factors, aquaculture area decreased from the middle to the nonh and south sides, the average yield level decreased from the nonheast to the southwest and the number of freshwater fish fry decreased from the nonh to the south. And the aquaculture labor force transited from negative value to positive value from the southeast to the west, and gradually increased. [Conclusion] The research on the spatial pattern and influencing factors of aquaculture in Sichuan province would provide a scientific basis for the intensive and differentiated development of aquaculture in this province, and would be one of the effective means to optimize the layout of aquaculture in Sichuan province and then promote the sustainable development of the industry. [ABSTRACT FROM AUTHOR]

[Objective]The present paper aimed to clarify the effects of processing parameters on the main chemical components, appearance quality and sensory quality of tobacco leaves during withering period of imitating black tea methods. [Method] Taking the middle leaves of Yunyan 87 as materials, the main chemical composition, appearance and sensory quality of tobacco were determined. By analyzing the correlation between wilting conditions and main chemical components, cut tobacco appearance and smoking evaluation results in tobacco, the change trend of tobacco quality and the optimal wilting conditions were obtained. [Result] Comparing the main chemical components of tobacco leaves in withering stage, the internal chemical components were similar to those of flue-cured tobacco after withering; The withering temperature was significantly positively correlated with the contents of total sugar, reducing sugar and potassium ion in tobacco leaves; The withering time was significantly positively correlated with the contents of total sugar, and negatively correlated with the contents of nicotine and total nitrogen; The results showed that the withering temperature had a great influence on the content of the main chemical components in the cured tobacco leaves, which was significantly positively correlated with total sugar, reducing sugar, potassium ion, sugar nicotine ratio, nitrogen nicotine ratio, potassium chloride ratio, significantly negatively correlated with nicotine and chloride ion, and significantly negatively correlated with total nitrogen; Comparing the appearance of cut tobacco, it can be seen that when the withering time was short, the cut tobacco was easy to appear green marks. Within the reasonable withering conditions, the appearance quality difference was small, when the withering temperature was high, and the withering time was long, it was easy to wither excessively, leading to the gray color of cut tobacco. The results showed that prolonging withering time was beneficial to the total score of miscellaneous gas, irritation and smoking evaluation, and increasing withering temperature was beneficial to the overall smoking evaluation. [Conclusion] Withering temperature of 41 oC, withering time of 36 hours, the chemical composition of tobacco leaves was suitable, the appearance performance was better, the highest evaluation score and the best modulation effect. The study showed the correlation between withering conditions and the chemical composition meanwhile the optimal withering process parameters were found in the experimental range. The quality of tobacco leaves can be controlled by controlling withering conditions, which provides a direction for the improvement of the processing technology of imitation black tea. [ABSTRACT FROM AUTHOR]

[Objective]The present paper aimed to optimizating the fertilization technology that is suitable for flue-cured tobacco in Zhaotong tobacco area under the current situation, a 3 -year in situ experiment was conducted. [Method] Different fertilization ratios of field experiments were carried out in 3 consecutive years in Zhaoyang tobacco area by single factor randomized block design. By comparing the agronomic characters, economic characters and leaf quality of flue-cured tobacco under different treatments, the optimal nitrogen application rate and the optimal ratio of nitrogen and phosphorus were determined. [Result] The results showed that with the extension of planting years, the qualities of agronomic traits of flue-cured tobacco decreased, and the occurrence of disease increased. The yield increased slightly, but the proportion of high-quality tobacco leaves, the appearance quality of cured tobacco leaves and the coordination of chemical components of tobacco leaves showed a downward trend. In the comparison of different treatments, the amount of nitrogen application had a certain relationship with the maturity of tobacco leaves. In order to ensure the timely yellowing of tobacco leaves, it was necessary to control the nitrogen application rate. With the increase of nitrogen application rate, the leaf color of tobacco turned from light green to dark green, and the agronomic traits of flue-cured tobacco showed an increasing trend. Under the same nitrogen application rate, the plant height and effective leaf number increased when more phosphorus were applied. The dis ease incidence of non fertilization treatments was higher than that of other treatments, but there was little difference in the disease incidence among fertilization treatments. The coordination between economic characters and tobacco chemical composition in the treatment of 97. 5 and 120 kg/hm² nitrogen application was better than that of the treatment of 75 kg/hm² nitrogen application, and the treatment of 97. 5 kg/hm² nitrogen application showed better performance. Under the same nitrogen application rate, the coordination of economic characters and chemical composition of tobacco leaves in the N/ P ratio of 1: 1. 8 was better than that in the N/ P ratio of 1: 1.2. [Conclusion] In the continuous cropping plots of Zhaotong tobacco area, when the nitrogen application rate is 97. 5 kg/hm², and m (N) : m (P2O5): m (K2O) is 1: 1.8: 3, tobacco leaves can turn yellow in time, and the coordination of agronomic characters, economic characters and chemical components of flue-cured tobacco are good, and good yield and high quality of flue-cured tobacco can be achieved. [ABSTRACT FROM AUTHOR]

[Objective ] The present paper discusses the land use change and ecological effect of Kaxgar River Basin from 1990 to 2018. [Method] Using the methods of land use dynamic index, land use intensity, land use gravity center, land use information entropy and equilibrium degree, combined with the value of ecosystem services, the land use change and its ecological effects in the Kashgar River Basin were analyzed from the perspective of spatial coupling. [Result] The land use of Kaxgar River Basin changed significantly from 1990 to 2018, and the cultivated land expanded rapidly, with a growth rate of 41. 95 % . The newly increased cultivated land mainly came from medium and low coverage grassland and unused land. The change of forestland was relatively stable and slightly increased. The grassland showed a decreasing trend, with an increase of 1967. 57 km² for high coverage grassland and a decrease of 4113. 02 km² for medium and low coverage grassland. Since 29 years, the area of water has decreased sharply, with a decrease of 53. 69%, and most of the area has been converted into unused land. The expansion of construction land was the most obvious, with a dynamic attitude of 21. 53 %, which was mainly transformed from cultivated land. In addition, the center of gravity of unused land gradually moved to the northwest and formed the spatial coupling relationship of 'desert-oasis-mountain' with the migration direction of cultivated land, water and grassland center of gravity. Information entropy and equilibrium degree showed a trend of rising first and then falling. With the acceleration of urbanization, the population continues to increase, the economic scale expands gradually, and the intensity of land use continues to increase. The ecosystem service value showed a state of first benefit and then loss under the main effect of grassland, waters and cultivated land changes, and there was a trend of continuous loss in the future. [ Conclusion] In the context of climate change, the continuous expansion of arable land, grassland degradation, and water scarcity have formed a spatial and temporal coupling, and the value of ecosystem services has gradually declined, posing a threat to the ecological security of basin. [ABSTRACT FROM AUTHOR]

[Objective]The present paper aimed to provide reference for screening low accumulation Cd cabbage varieties, the enrichment pattern of Cd in different varieties of cabbage and the safe limit value of Cd in cultivated soil was studied. [ Method ] Through pot experiment, six varieties of cabbage 'Zhongqingmaye' 'Mayehuoguocai' 'Gaokang 100' 'Kangbingdamaye' 'Jiwopadibai' 'Houye zaoshu 5') were studied for their biomass changes, Cd content from edible fraction, enrichment characteristics and the correlation between different varieties of cabbage and soil Cd content under the conditions of Cd concentration of O (CK), 0. 3, 0 . 6, l. 2, 2.4, 4. 8 mg/kg, respectively. [Result] There was not toxicity observed in cabbage with increasing Cd concentration. The Cd enrichment coefficients of different cabbage edible parts were 'Zhongqingmaye' (1. 61) > 'Kangbingdamaye' (1. 3 8) > 'Hou ye zaoshu 5' (1. 3 0) > 'Gaokang 100' (1. 02) > 'Mayehuoguocai' (0. 76) > 'Jiwopadibai' (0. 64 ). The enrichment coefficient of ' Mayehuoguocai' and 'Jiwopadibai' were less than l. According to Logistic equation, the correlation between Cd content from edible fraction of cabbage and Cd concentration in soil was significant, as 'Zhongqingmaye '(0. 9981) > 'Mayehuoguocai' (0. 9979 ) > 'Gaokang 100' (0. 9976) > ' Kangbingdamaye' (0. 9968) > 'Jiwopadibai' (0. 9949) > 'Houye zaoshu 5' (0. 9949). The corresponding safety limit values of Cd in soil for different cabbages were 'Jiwopadibai' (0. 30 mg/kg) > 'Gaokang 100' (0. 24 mg/ kg) > 'Mayehuoguocai' (0. 17 mg/kg) > 'Hou ye zaos hu 5' (0. 12 mg/kg) > 'Kangbingdamaye' (0. 09 mg/kg) > 'Zhongqingmaye' (0. 06 mg/kg). [Conclusion] Based on the tolerance and enrichment capacity of cabbage to Cd in soil and the corresponding soil safety limit value, 'Mayehuoguocai', 'Jiwopadibai' and 'Gaokang 100' were the low accumulation varieties of Cd. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the biological characteristics of a wild Lentinula edodes and the fermentation of different additives on the antioxidant activity of lentinan polysaccharide in mycelium, and to lay the foundation for the preparation of high vitality strains and the development of functional products. [Method] Colony diameter and dry weight of mycelium were used as main indexes, the biological traits and growth of mycelium of tested strains under different carbon and nitrogen sources, culture temperature and initial pH were studied by solid and liquid culture. Meanwhile, the scavenging effects of Lentinan on DPPH,ABTS and hydroxyl radicals were further determined by adding fermented liquid Huangzhu grass (HLNT) and Chinese medicine residue (ZLNT). [Result] The best carbon and nitrogen sources in the solid medium were glucose and ammonium sulfate, and the optimum culture temperature was 25-30 °C, initial pH 4. 0 - 6. 0. When sucrose was used as carbon source, ammonium sulfate or peptone as nitrogen source, mycelium biomass was accumulated in liquid medium. The culture temperature 25 °C, inoculation amount 3% (v/v) and pH 6. 0 were suitable conditions. ZLNT had significant scavenging effect on DPPH and hydroxyl radicals, as the concentration was 5 mg/ mL, the scavenging rate was 86. 7% and 73. 5%, respectively. The scavenging rate of HLNT with 5 mg/mL concentration to ABTS radical was 75. 5%. [Conclusion] The nutritional requirements and cultivation conditions suitable for mycelia growth of the wild L. edodes were preliminarily screened, and the strain showed better suitability for byproducts, which antioxidant activity of the liquid fermentation could be promoted by adding the byproduct immersion solution. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed optimize the preparation process of compound coating antistaling agent of thistle polysaccharide and nomilin and evaluate the effect of this coating treatment on the postharvest decay and quality deterioration of lemon fruits during cold storage. [Method] Response surface methodology (RSM) based on a nine-factor-three-level full central composite design was conducted. Meanwhile, the effects of compound coating antistaling agent of thistle polysaccharide and nomilin on the physiological metabolism, storage quality and antioxidant activity in lemon fruit during cold storage were investigated. [Result] The lowest decay incidence (6. 07%) and highest values of Vitamin c content (156. 02 µ.g/g), TSS/TA (1. 15) and limonin content (268. 80 µ.g/g) were achieved by the coating treatment of a content of thistle polysaccharide at 64. 65 g, the content of nomilin at l. 90 g and the ratio of thistle polysaccharide solution and nomilin emulsion at 2. 01 : l. Moreover, the relative error of the established model for preservation efficiency was 0. 95 % compared with the actual values, indicating that the established multiple quadratic regression model possessed a high fitting degree. Furthermore, the coating treatment combined of thistle polysaccharide and nomilin exhibited no significant difference compared with the prochloraz treatment in fruit decay rate. In addition, the malondialdehyde content and relative conductivity in the lemon fruit treated with this optimized coating agent were lower and the total sugar, total phenol and total flavonoid as well as the antioxidant capacity were clearly higher than the controls during the cold storage period for 24 weeks at 4 °C, which indicated that this coating treatment can not only significantly reduce the decay rate of lemon fruit, but also effectively delay the senescence process of the fruit to maintain their overall quality. [Conclusion] Therefore, the study showed that the coating agent of thistle polysaccharide combined with nomilin can be employed as an effective and environment-friendly preservative of lemon fruit, which helps to reduce the use of chemical fungicides. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to analyze the effects of different chemicals (fertilizers) on the prevention and control of ratoon chlorosis as well as the influence of growth and yield in sugarcane to provide a reference for the high-efficient and low-cost control of ratoon chlorosis in sugarcane. [Method] Using a randomized block design, setting up 6 chemical treatments(fertilizers) in a first ratoon field in 2020, treatment A was spraying iron fertilizer on the leaf surface at 3-leaf stage seedlings, treatment B was 10. 0 kg/667 m² ferrous sulfate applied to the soil before emergence, treatment C was 20. 0 kg/667 m² of hydrated lime applied to the soil before emergence, treatment D was 500. 0 g/667 m² (diluted 3000 times) of soil irrigating and repairing bacteria in the root zone before emergence, treatment E was 1. 0 t/667 m² of biochar applied in the soil before emergence, treatment F was 1. 0 t/667 m² coal ash from the sugar mill before emergence, and no treatment was using as a control (CK). Seventy days after treatments, the incidence of chlorosis in the current year and the consequent ratoon year were counted, and agronomic characteristics such as plant height, tiller rate, number of leaves, and yield components such as millable stalks and stalk diameter were compared with the control, and were used in evaluation the control effects. [Result] The tested chemicals (fertilizers) had extremely significant (P < 0. 01, the same as below) control effects on sugarcane ratoon chlorosis, the range of control effect was 5. 57% to 71. 33% in year 2020, and 1. 96% to 73. 67% in year 2021. In 2020, treatment A (foliar spraying iron fertilizer) had the best control effect, with the 71. 3 3 % control effect, next was the treatment F (sugar factory coal ash) with 30. 01 % control effect. Treatment B and D had poor effect, and the difference was not significant (P > 0. 05), but both were significantly worse than other soil modulators (fertilizer) treatments. In 2021, the control effect of each soil modulator (fertilizer) treatment was extremely significantly different, and significantly (P < 0. 05, the same as below) or extremely significantly better than in 2020, especially the best treatment effect was F, reaching 90. 06%, followed by treatment E, and the control effect was 73. 67 %. All treatments can significantly promote plant growth, increase tillers, and leaves, in addition to extremely significantly improve the yield traits. Among them, treatment F performed the best effect. The cost of each treatment was in the range of 70 - 2100 yuan/667 m², and costs from high to low was E >A > F > C > D > B. [Conclusion] Foliar spraying with Fe2+ foliar fertilizer has a significant re-greening effect on sugarcane seedlings that have ratoon chlorosis, can quickly recover the yield loss caused by ratoon chlorosis, but the control time is short, and it is difficult to fundamentally prevent ratoon chlorosis of sugarcane. Considering the control effects, as well as cost and the influence of sugarcane growth, the applying coal ash 1. 0 t/667 m² is the best way to prevent and cure sugarcane ratoon chlorosis and sugarcane early growth and yield. [ABSTRACT FROM AUTHOR]