【Objective】To quantitatively analyze the yield gap of wheat following rice in Anhui Province and clarify the space for increasing yield and improving utilization efficiency of resource of wheat following rice.【Methods】Four cultivation patterns：super high yield（SH）,high yield and high efficiency（HH）,farmer pattern（FP）and inherent soil productivity（ISP）and three difference levels：first-level yield gap（FP-ISP）,second-level yield gap（HH-FP）,and third-level yield gap（SH-HH） were set up in wheat following rice areas along the Huai River,between Yangtze River and Huai River,and along the Yangtze River in Anhui Province from 2017 to 2020. The dry matter accumulation and leaf area index of over-wintering stage,jointing stage,anthesis stage,filling stage and maturity stage were determined and the effective ear number,kernels per ear,1 000-grain weight and economic coefficient,as well as yield were measured at maturity stage.【Results】Along the Huai River,between Yangtze River and Huai River,and along the Yangtze River in Anhui Province,the first-level yield gap（FP-ISP） of wheat following rice was the largest,with an average of 3 009.6 kg/hm². The second-level yield gap and the third-level yield gap were 768.5 and 758.0 kg/hm²,respectively. Yield gaps varied among different wheat following rice planting regions,with the first-level yield gap decreased gradually from north to south,the second-level yield gap increased slightly from north to south,and the third-level yield gap in the north slightly higher than that of the south. The yield gap of the different levels varied greatly among different years. The effective measures to narrow the first-level yield gap were to increase the effective ear number,kernels per ear,biological yield,economic coefficient and leaf area index in jointing stage.The effective measures to narrow the second-level yield gap were the enhancement of kernels per ear,biological yield and dry matter in anthesis stage. The effective measures to narrow the third-level yield gap were to increase the effective ear number and economic coefficient. Sink number,sink volume,leaf area index in over-wintering stage and jointing stage and dry matter accumulation after flowering were extremely significantly positive correlated（P<0.01） with the yield of wheat following rice. Nitrogen agronomic utilization efficiency,light and accumulative temperature utilization efficiency increased with the improvement of yield.【Conclusion】Increasing grain sink number,expanding sink capacity and improving grain sink quality were the effective means to narrow the yield gap and increase yield of wheat following rice in Anhui Province.

【Objective】To investigate the release patterns of heavy metals in the soils around tailings in western Inner Mongolia.【Methods】The leaching release characteristics of heavy metals Cu,Zn,As and Pb in the soil around tailings in Bayannur City,Inner Mongolia were investigated by leaching experiments. Four treatments,0（CK）,1%,2% and 3% humic acid addition were set up. Heavy metal leaching kinetics experiments were carried out using column leaching apparatus,then fitted with the first order kinetic equation,modified Elovich equation,double constant rate equation and parabolic diffusion equation.【Results】Humic acid addition increased the content of the four heavy metals in the organic bound state in the soil by 0.78%-86.83% compared to CK. The leaching amount of all the four heavy metals were in large quantities when leached for 72 h. Then with the leaching time extended,and the release of heavy metals increased slowly. The cumulative release amount of the four heavy metals was in the order of：Cu>As>Zn>Pb. When 3% humic acid was added to the soil,Cu and As were significantly lower（P<0.05）than CK by 16.85% and 5.41%. The modified Elovich equation could simulate the release process of heavy metals Cu,As and Pb well. While the double constant rate equation could simulate the release process of heavy metal Zn well.【Conclusion】Humic acid addition could change the occurence form of heavy metals in the soil,reduce the leaching volume of heavy metals and lessen the risk of contamination when heavy metals were transported and transformed.

【Objective】Understand the heterosis of island-upland hybrid cotton and island-island hybrid cotton,in order to provide theoretical basis for the breeding of mechanical harvesting hybrid long-staple cotton varieties.【Methods】The long fruit branch,zero fruit branch island cotton and early-maturing,high-yield and insect-resistant long fruit branch upland cotton varieties（lines）were used as parents,hybrid cotton combinations of island-upland hybrid cotton and island-island hybrid cotton were made. The plant characters,boll traits and fiber quality of parents and hybrid cotton were compared.【Results】Island-island hybrid cottons had compact plant-type,small bolls,low lint percentage,low sterile seeds rate,and superior fiber quality. The three island-island hybrid cotton had an average fibre length of 36.0 mm,fibre strength of 45.9 cN/tex and micronaire value of 3.5. The island-upland hybrid cotton had loose tower plant-type,big bolls,high lint percentage,and high sterile seeds rate. Among them,the fiber quality of WT114×Xinhai No. 51 and WT117×Xinhai No. 63 met the quality standards of long-staple cotton.【Conclusion】Island-island cotton hybridization could breed super long-staple cotton varieties（lines）. With proper hybridization,the fiber quality of island-upland hybrid cotton varieties（lines）could reach the long-staple cotton standard as well. Island-upland hybrid cotton was suitable for large area mechanical harvesting.

【Objective】To screen soybean varieties with high yield,superior quality and strong resistance suitable for planting in the north foot of Yinshan Mountains.【Methods】Variety comparison experiment was conducted on 20 soybean varieties provided by the Institute of Hulun Buir Agricultural Science to analyze the yield and quality traits. Cluster analysis and principal component analysis were used to comprehensively evaluate different soybean varieties.【Results】Cluster analysis divided the 20 varieties into three categories. The first category（Mengdou 50,Dengke No. 5,Mengdou 49,Dengke No. 1,Mengdou 58,Mengdou 912,Mengdou 57,Mengdou 42,Mengdou 1137,Mengdou 43,and Mengdou 160） comprehensively displayed the characteristics of high yield and high fat content,that was,high yield and superior quality. The second category（Mengdou 53,Mengdou 54,Mengdou 343,Mengdou 46,Mengdou 48,Mengdou 15,Neidou No. 4） had low yield and moderate quality. The third category（Dongnong 690） had high yield and low fat content. Principal component analysis showed that the yield factor and grain factor had contribution rates of 45.298% and 41.496%,respectively. The effective pods per plant,total seeds per plant,yield per plant,plot yield,fat content,and 100-seed weight all had high contribution.【Conclusion】Based on the results of principal component comprehensive evaluation ranking and cluster analysis,combined with comprehensive factors such as variety growth period and resistance,eight soybean varieties with good comprehensive performance were selected,including Mengdou 50,Mengdou 43,Mengdou 1137,Dengke No. 5,Mengdou 42,Mengdou 58,Mengdou 49,and Dengke No. 1. These soybean varieties were suitable for demonstration and promotion planting in the north foot of Yinshan Mountains.

【Objective】To compare the flavonoids content in different parts of Epimedii Folium from Hanzhong City,Shaanxi Province,in order to provide theoretical basis for quality control of Epimedii Folium in the region.【Methods】The above-ground and underground parts of 17 batches of Epimedii Folium plants were collected from the nine counties and two districts in Hanzhong City and divided into four parts：roots,stems,petioles,and leaves. High performance liquid chromatography（HPLC） was used to determine the six flavonoids of epimedin A1,epimedin A,epimedin B,epimedin C,icariin,and baohuoside Ⅰ. The content differences of Epimedii Folium in the four parts were detected and analyzed. The Epimedii Folium characteristic fingerprints of all the samples were constructed by HPLC,and the common peaks were determined and identified by the similarity evaluation system of traditional Chinese medicine fingerprints. Finally,HPLC fingerprints of the 17 batches of samples were drawn.【Results】The contents of six components in Epimedii Folium leaves were clearly higher than that of petiole and stem. The six components in the root differed greatly with the content of epimedin C ranging from 0.536% to 4.712%. The total content of the six components in roots,stems,petioles and leaves were 0.616%-5.141%,0.006%-0.136%,0.007%-0.271%,and 0.588%-5.100%,respectively.Six common peaks of epimedin A1,epimedin A,epimedin B,epimedin C,icariin,and baohuoside Ⅰ in the 17 batches of samples were identified by Chinese medicine fingerprints,with similarities of roots,stems,petioles and leaves at 0.962-1.000,0.791-0.990,0.728-0.996,and 0.629-0.995,respectively.【Conclusion】The quality difference of roots,stems,petioles and leaves of Epimedii Folium from Hanzhong was determined based on multi-component content test.The HPLC fingerprint of Epimedii Folium from Hanzhong was established.

【Objective】To isolate and identify the pathogens of sclerotinia rot in milk thistle planting regions in Hulun Buir,Inner Mongolia,and to clarify the control effect of different chemical agents on milk thistle sclerotinia rot.【Methods】The milk thistle sclerotinia rot disease samples were collected for pathogen isolation and purification,then verified by Koch′s Postulation,and identified by morphological and molecular biology. Using water as control,40% Dimethachlon WP,“Pulvtong” plant immune protein,450 g/L Prochloraz EW,50% Carbendazim WP as test agents,the control effect of the four agents on milk thistle sclerotinia rot and their effect on yield of milk thistle were analyzed.【Results】A total of 15 strains were isolated and purified. The NCBI Blast results showed that the isolated strains were >99% similar to Sclerotinia sclerotiorum（Lib.）de Bary. The four test agents all effectively increased the yield of milk thistle,with the control effect in the range of 32.77%-53.78%,and yield increase rate at 16.31%-37.05%.Spraying 2 999 g/hm² of “Pulvtong” plant immune protein had the best control effect on sclerotinia rot（control effect at 53.78%） and good yield increase effect（yield increase rate at 16.88%）. Spraying 450 g/L Prochloraz EW had poor control effect（control effect at 32.77%）,but best yield increase effect（yield increase rate at 37.05%）.【Conclusion】The four test agents were all safe to milk thistle.Spraying 2 999 g/hm² of “Pulvtong” plant immune protein had highest control effect and good yield increase rate,could be used as the preferred agent for the prevention and control of sclerotinia rot in milk thistle planting regions in Hulun Buir,Inner Mongolia.

【Objective】To screen biocontrol bacteria having control efficacy against oat anthracnose.【Methods】Using plate antagonistic test and growth promoting pot test,four treatments were set up including,spraying clear water（CK）,spraying anthrax spore suspension,spraying anthrax spore suspension plus Bacillus megaterium L6 suspension,and spraying Bacillus megaterium L6 suspension. The activity of Phenylalanine ammoniase lyase（PAL） and the content of Malondialdehyde（MDA）were measured and calculated by UV-VIS spectrophotometer.【Results】L6 strain and Bacillus megaterium OUCMDZ4181 were grouped together by phylogenetic analysis,and were identified as Bacillus megaterium. Plate antagonism test showed that the inhibition rate of Bacillus megaterium L6 strain to anthrax was 89.89%. After anthrax spore suspension plus Bacillus megaterium L6 suspension treatment,the content of MDA in 9 d decreased to 28.07% of that of anthrax spore suspension treatment,whereas the activity level of PAL increased compared with anthrax spore suspension treatment. Both inoculation of Bacillus megaterium L6 strain alone and combined inoculation with anthrax had growth promoting effect on oat plants,with the growth promoting rates of seedling height and root length of 15.13%,25.40% and 11.06%,17.24%,respectively.【Conclusion】The Bacillus megaterium L6 strain could stimulate the induced resistance of oat to anthrax and promote the growth of oat root and seedling.

【Objective】To determine the safety on the growth of chickpea and the control efficacy on broad leaf weeds of different foliar-applied herbicides.【Methods】Treatments of 25% fomesafen AS（750,1 125,1 500 mL/hm²）and 480 g/L bentazone AS（2 250,3 000,4 500 mL/hm²） were set up,with water treatment（CK1） and artificial weeding（CK2） as control. In randomized block arrangement the effects of different application rates of the two foliar-applied herbicides on the growth,yield,and 100-grain weight of chickpea,as well as the control efficacy on broad leaf weeds were analyzed after treatment.【Results】25% fomesafen AS was safe for chickpea at all three doses. The total weed control efficacy was 1 500 mL/hm²>1 125 mL/hm²>750 mL/hm². The plant control efficacy of 1 500 mL/hm² treatment on broad leaf weeds were over 90%,and the fresh weight control efficacy were 96.39%. After applying 480 g/L bentazone AS,the pesticide damage in the 4 500 mL/hm² application area was serious,and 80% of chickpea plants died after 7 d. Chickpeas in the 3 000 mL/hm² and 2 250 mL/hm² application areas had different degrees of slight pesticide damage and returned to normal growth after 15 d. However the yield and 100 grain weight decreased greatly,extremely significantly different compared to the CK1 with poor safety.【Conclusion】25% fomesafen AS 1 500 mL/hm² uniform sprayed on stem and leaf could effectively control broad leaf weeds in chickpea field. 480 g/L bentazone AS was not safe for chickpea at the experimental dose and was not suitable for chickpeas field.

【Objective】To clarify the effect of microbial agents on the control efficacy of potato black scurf and Verticillium wilt in field and the yield of potatoes.【Methods】Using randomized blocks design,five treatments were set up including Trichoderma harzianum WP,Bacillus amyloliquefaciens SC,Endophytic Bacillus spp. agent,Bacillus subtilis microbial agent and no agent application（CK）. Potato seedling emergence rate was investigated in seedling stage. The diseases incidence of potato black scurf and Verticillium wilt and yield were recorded in harvest period. The differences in potato emergence rate,control efficacy,and yield among different treatments were analyzed.【Results】All the four microbial agents did not affect the seedling of potatoes with seedling emergence rate all above 95.00%. The control efficacy on potato black scurf was better than that on potato Verticillium wilt. The four microbial agents had control efficacy ranging from 54.56% to 65.01% on potato black scurf,24.89% to 41.34% on potato Verticillium wilt,and 5.41% to 13.39% for yield increase rate. Bacillus amyloliquefaciens SC had control efficacy of 60.08% and 41.34% on potato black scurf and Verticillium wilt,respectively,and yield increase rate at 8.95%. The control efficacy of Endophytic Bacillus spp. agent on potato black scurf and Verticillium wilt were 65.01% and 32.12%,respectively,with yield increase rate at 13.39%.【Conclusion】Bacillus amyloliquefaciens SC and Endophytic Bacillus spp. agent had better control efficacy on potato black scurf and Verticillium wilt with good yield increase as well,could be used as biocontrol agents for potato soil-borne disease.

【Objective】To study the effect of 1-Methylcyclopropene（1-MCP） on postharvest low temperature storage quality of Xinfengmilu peach fruit.【Methods】At low temperature of（1.0±0.5） ℃,four 1-MCP treatments,0（CK）,0.5,1.0,and 1.5 μL/L were set up to analyse the effect of 1-MCP on Xinfengmilu peach fruit postharvest storage fruit firmness,soluble solid content,respiratory rate,titratable acid content,sound fruit rate,weight loss rate using Xinfengmilu peach fruit as experiment material.【Results】During low temperature storage,the decline rate of Xinfengmilu fruit firmness of 0.5 μL/L 1-MCP treatment was relatively slow,and maintained at high level after 20 d and 25 d of postharvest storage,significantly higher than 1.0 μL/L and 1.5 μL/L 1-MCP treatment（P<0.05）. On the 25 d of storage,the titratable acid content of 0.5 μL/L 1-MCP treatment was the highest at 0.59%,extremely significantly higher than CK（P<0.01）,and significantly higher than 1.0 μL/L and 1.5 μL/L 1-MCP treatment（P<0.05）. The respiratory rate change of CK was faster than the three 1-MCP treatments,and the activity was high. The respiratory rate of CK reached the highest on the 10th day of storage,at 81.23 mg/（kg·h）. After 10 d storage,the fruit weight loss rate of 0.5 μL/L 1-MCP treatment was significantly lower （P<0.05） than 1.0 μL/L and 1.5 μL/L 1-MCP treatment.【Conclusion】At the concentration of 0.5 μL/L 1-MCP treated Xinfengmilu peach fruit had the best postharvest storage performance,making it a suitable choice for maintaining high quality fruit during storage.

【Objective】Study the effects of reduced chemical fertilizer application on the growth and fruit quality of facility watermelon,to seek for the optimal fertilization plan.【Methods】Taking Qianli No.4 as the research object,five fertilizer gradient treatments were designed,including conventional fertilization（CK）,10% chemical fertilizer reduction（T1 treatment）,20% chemical fertilizer reduction（T2 treatment）,30% chemical fertilizer reduction（T3 treatment） and 40% chemical fertilizer reduction（T4 treatment）. During the growth period of watermelon,growth indexes such as plant extension days,pollination days,and fruit setting nodes were investigated. After fruit maturation,quality indicators such as single fruit weight, fruit longtitudinal and transverse diameter,peel thickness,and sugar content as well as the yield were measure.【Results】The pollination days of the T3 treatment were 65.67 d,significantly different with CK（P<0.05）. The edge sugar content of the T1 treatment was 9.40%. With the decrease of chemical fertilizer application,the sugar content of watermelon showed decreasing trend. The central sugar content of T2 treatment decreased significantly（P<0.05） in comparison with CK. The edge sugar content in T4 decreased to 7.87%,significantly different（P<0.05） with CK. Compared with CK,reduced chemical fertilizer application decreased the peel thickness of watermelon. T1 treatment had the highest watermelon yield of 39.98 t/hm² while T4 treatment had the lowest watermelon yield of 33.49 t/hm². The yield of the different treatment had no significant difference（P>0.05）. Fertilizer factor was positively correlated with peel thickness and edge sugar content,with correlation coefficients of 0.62 and 0.59,respectively. The higher the fertilizer application rate,the thicker the fruit peel and the higher the edge sugar content.【Conclusion】Without affecting the growth and the fruit quality of watermelon,reducing the application amount of chemical fertilizer in the base fertilizer appropriately could achieve the goal of reducing fertilizer while improving efficiency. Taking into account the growth indexes,fruit quality indicators,and yield of watermelon,10% chemical fertilizer reduction（Basal application of potassium sulfate compound fertilizer 675 kg/hm²） was optimal.

【Objective】To measure Chinese agricultural carbon emissions and carbon emission intensity,explore the time variation characteristics,analyze the driving factors of agricultural carbon emissions,in order to provide theoretical basis for achieving green,low-carbon and high-quality agricultural development.【Methods】Based on relevant data on agriculture and energy in 29 provinces（autonomous regions and centrally administered municipalities） from 2000 to 2020,combined with IPCC classical carbon emission measurement method,carbon emission measurement system was built around three aspects：agricultural land use,agricultural inputs and livestock and poultry breeding. The driving factors of agricultural carbon emissions were analyzed using the LMDI model.【Results】From 2000 to 2020,Chinese agricultural carbon emissions increased from 27.790 0 million t to 29.409 6 million t,while the agricultural carbon emission intensities decreased from 1.329 t/ten thousand yuan to 0.618 t/ten thousand yuan. From regional perspective,central and eastern were the main regions of Chinese agricultural carbon emissions. The contribution values of agricultural industrial structure,agricultural labor force size and agricultural energy structure to agricultural carbon emissions were -24.284 3 million t,-12.048 6 million t and -10.240 5 million t respectively. While the contribution values of agricultural energy efficiency and agricultural economic level were 37.865 7 million t and 10.327 3 million t respectively.【Conclusion】Chinese agricultural carbon emissions as a whole showed a trend of “rise-fluctuation rise-fluctuation drop”. The total and intensity of agricultural carbon emissions in regions with high levels of economic development had high reduction rate. The main regions of agricultural carbon emissions were concentrated in the central and eastern regions. Agricultural industrial structure,agricultural labor force size,and the agricultural energy structure played positive roles in achieving agricultural carbon emission reduction,while agricultural energy efficiency and agricultural economic level promoted agricultural carbon emissions to a certain extent.

【Objective】Optimize the extraction process of banana peel polysaccharides and study the antioxidant activities,in order to provide references for the industrial extraction and utilization of banana peel polysaccharides.【Methods】Using the polysaccharides yield as the indicator,the effects of grinding time,solid-liquid ratio,cellulase addition amount,ultrasonic time,ultrasonic temperature on the yield of banana peel polysaccharides were investigated through single factor experiment.Response surface method were used to optimize three factors,solid-liquid ratio,ultrasonic time,and ultrasonic temperature,to determine the optimal process for ultrasonic assisted enzymatic extraction of banana peel polysaccharide. The antioxidant activities of the extracted banana peel polysaccharides were tested as well.【Results】Under different factor levels,the yield of banana peel polysaccharides was the highest at 4.15% when the grinding time was 60 s. When the solid-liquid ratio was 1∶40（g∶mL）,the yield of banana peel polysaccharides was the highest at 5.87%. When the cellulase addition amount was 2.5%,the yield of banana peel polysaccharides was the highest at 5.49%. The yield of banana peel polysaccharides was the highest at 5.72% when the ultrasonic time was 20 min. The yield of banana peel polysaccharides was the highest at 5.97% when ultrasonic temperature was 30 ℃. Under the conditions of 60 s grinding time,solid-liquid ratio of 1∶38（g∶mL）,cellulase addition amount at 2.5%,19 min ultrasonic time,and ultrasonic temperature at 26 ℃,the yield of banana peel polysaccharides was the highest at 6.51%. The scavenging abilities of banana peel polysaccharides on hydroxyl radicals,DPPH radicals and ABTS radicals increased with the increase of banana peel polysaccharides concentration.【Conclusion】Response surface method determined that the optimal conditions for ultrasonic assisted enzymatic extraction of banana peel polysaccharides were：60 s grinding time,solid-liquid ratio of 1∶38（g∶mL）,cellulase addition amount at 2.5%,19 min ultrasonic time,and ultrasonic temperature at 26 ℃. Banana peel polysaccharide had obvious scavenging effect on hydroxyl radicals,DPPH radicals and ABTS radicals.

【Objective】Study on rice production pattern evolution characteristics and the influence mechanisms in Jiangsu Province.【Methods】Based on the panel data of rice production in different City areas in Jiangsu Province from 2005 to 2020,using hot and cold spots,multiple regression,and mediating effect analysis methods,the rice production pattern evolution characteristics and the influence mechanisms in Jiangsu Province were analyzed.【Results】The rice production pattern in Jiangsu Province had obvious characteristics of “northward shift” and agglomeration.The rice sown area in the central region of Jiangsu slightly decreased,while the rice sown area in the northern region of Jiangsu had increasing trend. The impact coefficient of urbanization on rice sown area was -0.384. The improvement of urbanization level caused the decrease in rice planting area. Rice resource endowment,industrial upgrading,cultivated land resources,and rural agricultural labor force had impact coefficients of 0.051,1.755,0.884,and 0.749 respectively on rice sown area,and had positive promoting effects on rice sown area. Cultivated land resources had mediating effect on rice sown area,that is,in the process of urbanization,cultivated land resources determine the scale of rice sown area.【Conclusion】The rice production pattern in Jiangsu Province had obvious characteristics of “northward shift”. Urbanization had negative effects on the rice sown area,while rice resource endowment,industrial upgrading,cultivated land resources,and rural agricultural labor force had positive effects on rice sown area. Cultivated land resources had mediating effect on rice sown area.

【Objective】To clarify the research status,hotspots and trends of high quality agricultural development in China.【Methods】From October 30,2017 to April 30,2023,254 Chinese core literature and 46 foreign language literature were retrieved from CNKI database and Web of Science database.The bibliometric method and CiteSpace software were used to analyze research hotspots of high quality agricultural development in China from the aspects of publication trend,keywords frequency and keywords clustering. The research trends were analyzed based on keywords emergent.【Results】From 2017 to 2023,the number of publications in Chinese and foreign languages increased year by year. The gap between the two had a trend of “first expanding and then shrinking”. The keywords with highest frequency in Chinese and foreign language literature were “High quality development”（124 times）and “Performance”（12 times）respectively,while “Agriculture”（0.77）,“System”（0.33）and “Agriculture”（0.33）had the highest centrality,respectively. Eleven keywords clusters were in Chinese literature,including High quality development,High quality agricultural development,and new development concepts etc. Eleven keywords clusters in the foreign language literature included Green total factor productivity,Consumption upgrading,and the EKC model etc. The research hotspots in Chinese literature were the connotation,current situation,evaluation subjects,and influencing factors of high quality agricultural development. There was a consensus on the connotation interpretation and analysis of the current situation,which was that the high quality agricultural development was the development of new developmental concepts for the integration of innovation,coordination,green,openness,and sharing. The level of high quality agricultural development was relatively low,but on the rise,and regional development was unbalanced. The research hotspots for foreign language literature were green total factor productivity,green agricultural development,effects and mechanisms. The results of keywords emergent showed that the focus on digital economy,rural finance,ecological environment and agricultural total factor productivity was increasing year by year.【Conclusion】Research on high quality agricultural development is gradually increasing,focusing on the aspects such as interpretation of connotation,current situation,evaluation subjects,and influencing factors,with consensus conclusions reached in some fields. Exploring the impact of digital economy,rural finance,ecological environment and other factors on high quality agricultural development are the future research trends.