Current issue

• 2024 Vol.40 No.6 Published:25 February 2024

  The Effect of AM Fungi on Crop Growth in Continuous Cropping Soils: A Review CHEN Rui, CUI Zeyuan, LI Zhi, GENG Gui, YU Lihua 2024, 40 (6):  1-8.  DOI: 10.11924/j.issn.1000-6850.casb2023-0272 Abstract + ( 80 )   HTML ( 7 )   PDF ( 1194KB )   ( 43 ) Biological control has been one of the most important ways to prevent and control continuous cropping obstacle. AM fungi can form a symbiotic relationship with a wide range of crops and can effectively mitigate the stressful effects of crop succession on inter-root soils, soil microbial communities and plant growth. In order to better utilize the ameliorative effect of AM fungi on the continuous cropping obstacle in practical applications, the changes in soil physicochemical properties and soil microbiota under conditions of continuous cropping and inoculation with AM fungi were systematically summarized, as well as the effects of stress or mitigation on plant growth under the two conditions. Soil physicochemical properties deteriorate to a certain extent under continuous cropping conditions and are accompanied by an imbalance in soil microbial structure, and continuous cropping causes autotoxic effects on the next crop and also severely inhibits normal crop growth. The application of AM fungi can effectively play a mitigating role in the above aspects. At the same time, according to the current research status of AM fungi, the future research focus was put forward and briefly summarized. It was proposed that strengthening the pure culture technology of strains was still a key step, and better screening of crop genotypes and AM fungal strains was necessary to achieve better compatibility and symbiosis effect between the two.

  Effects of Different Fertilization Patterns on Rice Yield and Nutrient Use Efficiency QIAO Yue, HU Cheng, WAN Jianhua, XU Hualin, LIU Maojun, GUO Weihong, DAI Li, ZHANG Chunhua, DENG Chaoran 2024, 40 (6):  9-15.  DOI: 10.11924/j.issn.1000-6850.casb2023-0245 Abstract + ( 70 )   HTML ( 7 )   PDF ( 1299KB )   ( 21 ) To solve the problem of increasing the production capacity of middle and low yield rice fields in the middle and lower reaches of the Yangtze River, 6 treatments were set up for a field test in Dangyang, Hubei, including: local conventional fertilizer (T1), conventional compound fertilizer+3000 kg/hm2 bio-organic fertilizer (T2), organic-inorganic compound fertilizer (T3), biochar based fertilizer (T4), rice-specific formula fertilizer (T5) and non-fertilizer (CK). The effects of different fertilization modes on rice yield and nutrient utilization efficiency were studied under the same fertilization amount. The results showed that under different fertilization treatments, rice yield and yield components were T4>T5>T3>T2>T1>CK. Compared with T1 treatment, T2-T5 treatments increased yield by 4.27%-19.27%, respectively; under the same nitrogen application, the nitrogen accumulation of T2-T5 treatments increased by 4.08%-32.03% compared with T1 treatment, and T2-T5 treatments increased the nitrogen uptake, nitrogen contribution rate, nitrogen partial factor productivity, nitrogen agronomic efficiency and nitrogen apparent efficiency in the production of 100 kg seeds by 1.96%-9.15%, 11.26%-44.86%, 4.26%-19.27%, 16.23%-72.79% and 7.80%-61.22%, respectively; under the same phosphorus application treatment, the phosphorus accumulation of T2-T5 treatments increased by 4.60%-26.67% compared with T1 treatment, and T2-T5 treatments increased phosphorus uptake, phosphorus partial productivity and phosphorus apparent utilization rate in the production of 100 kg seeds by 4.28%-19.27%, 3.33%-10.00% and 12.48%-71.90%, respectively. Under the condition that the total amount of nitrogen, phosphorus and potassium fertilizer was the same, selecting appropriate slow-release fertilizer for basic application and rationally application of tillering fertilizer could not only improve the fertilizer absorption and utilization rate, but also increase the rice yield.

  Study on Grain Filling Characteristics of Different Wheat Crops ZHANG Shan, WANG Peiying, JIANG Xiaodong, CAI Chunhao, ZHENG Jianjie, YANG Zaiqiang 2024, 40 (6):  16-21.  DOI: 10.11924/j.issn.1000-6850.casb2023-0199 Abstract + ( 68 )   HTML ( 5 )   PDF ( 1312KB )   ( 24 ) In order to study the characteristics of grain-filling process of different wheat crops, the grain-filling process of wheat variety ‘Ningmai 13’, barley variety ‘Longpi 1’ and highland barley variety ‘Kunlun 15’ was simulated by Logistic model. The differences of grain weight growth process and grain-filling parameters of the three crops were analyzed. The results showed that the 1000-grain weight of wheat, barley and highland barley were 51.60 g/(1000grain), 49.01 g/(1000grain), and 46.43 g/(1000grain), respectively, with significant differences among them (P<0.05). The effective grain-filling time of wheat was 45.89 d, which was 9.84 d and 3.59 d longer than that of barley and highland barley, respectively (P<0.05). The duration of rapid and slow growth stages of wheat grain weight was significantly longer than that of barley and highland barley, while there was no significant difference between barley and highland barley. The average grain-filling rate of barley was 1.37 g/(1000grain·d), which was 18.10% and 24.55% higher than that of wheat and highland barley (P<0.05), respectively. The grain-filling rate of barley at the rapid growth stage, the slow growth stage and the maximum grain-filling rate were significantly higher than those of wheat and highland barley, and there was no significant difference between highland barley and wheat, but the grain-filling rate of barley decreased the fastest at the rapid growth stage. Therefore, the difference of grain weight among wheat, barley and highland barley mainly depends on the duration of grain-filling, and the difference of grain weight between barley and highland barley mainly depends on the grain-filling rate.

  Effect of Chemical Seed Dressing on Seedling Strength and Yield of Late-sowing Wheat in Huaihe River Region SHAO Wenqi, DONG Qingjun, DONG Yubing, ZHONG Ping, JI Li, CHEN Chuan, ZHANG Ankang 2024, 40 (6):  22-28.  DOI: 10.11924/j.issn.1000-6850.casb2023-0244 Abstract + ( 62 )   HTML ( 5 )   PDF ( 1175KB )   ( 22 ) Delayed sowing time can easily lead to a yield decrease in wheat. In order to explore the effect of chemical seed dressing on the seedling strength and yield of late sowing wheat, ‘Huaimai 40’ was used as the experimental material, and four different chemical seed dressing treatments were set up to investigate and analyze the data of wheat growth quality, grain yield, and other aspects. The results showed that chemical seed dressing could improve the seedling rate of wheat, reduce the seedling height, increase leaf age, and promote root growth and biomass accumulation. The seed dressing could increase tillering and effective panicle number, enhance the proportion of large panicles, and improve grain yield. Compared with the control, Y3 treatment promoted the seedling rate by 2.1%, reduced plant height by 11.9% before overwintering, increased leaf age by 16.4%, enhanced the width of the stem base by 58.2%, and increased the dry weight of the aboveground and root systems by 35.8% and 45.9%, respectively. The tillering ability was significantly enhanced, therefore the effective panicle number was increased by 12.4% with Y3 treatment. The grain number and thousand grain weight per panicle were enhanced, and grain yield was increased by 19.4% with Y3. In summary, Y3 treatment can enhance the growth quality of wheat and achieve yield stability and increase under the condition of delayed sowing of wheat.

  Effect of Uniconazole on Growth, Seed Yield and Quality of Prairie Grass TIAN Hong, LU Jiaoyun, ZHANG Heshan, XIONG Junbo, LIU Yang 2024, 40 (6):  29-35.  DOI: 10.11924/j.issn.1000-6850.casb2023-0238 Abstract + ( 53 )   HTML ( 2 )   PDF ( 1147KB )   ( 9 ) The effect of uniconazole on plant growth, seed yield and quality of prairie grass was explored in order to provide a scientific basis for the seed yield and quality improvement. The plant growth, seed yield and germination characteristics of prairie grass ‘Jiangxia’ were studied by spraying different concentrations of uniconazole (0 mg/kg, 50 mg/kg, 90 mg/kg and 130 mg/kg) at jointing stage in a random block design. The results showed that uniconazole reduced plant height and increased lodging resistance. Except that 50 mg/kg uniconazole significantly increased the reproductive branch number (P<0.05), other treatments had no significant effects on the second stem node length, stem diameter, tiller number of plants and reproductive branch number. The spikelet number/reproductive branch, seed number and yield of prairie grass were increased by spraying different concentrations of uniconazole, but the difference of the all indexes was significant only under 50 mg/kg treatment (P<0.05). 90 mg/kg uniconazole treatment significantly increased seed vigor index (P<0.05), but all treatments had little effect on 1000-seed weight, germination rate and germination index. Correlation analysis showed that plant height was positively correlated with lodging rate, tillers number and reproductive branch number (P<0.01). And seed yield was positively correlated with reproductive branch number (P<0.05). The highest seed yield of prairie grass was 1508.31 kg/hm2 when 50 mg/kg uniconazole was sprayed, which was 13.63% higher than that of the control and the difference was significant (P<0.05).

  Study on the Dynamics of Filament Vigor and Seed Setting of Maize Hybrids ZHAO Shuzheng, YANG Meili, LU Hongwei, SU Yujie, CHENG Jianmei, WANG Bangtai, QIN Guiwen 2024, 40 (6):  36-41.  DOI: 10.11924/j.issn.1000-6850.casb2023-0262 Abstract + ( 62 )   HTML ( 4 )   PDF ( 1132KB )   ( 8 ) The aim was to clarify the dynamic changes of filaments vigor and the setting rate at different day-ages of maize hybrids, and provide a better theoretical basis for maize breeding and production. This study selected maize hybrids ‘Yongyou 1573’ ‘Yongyou 1583’ and ‘Zhengdan 958’ as experimental materials to measure their daily silk production quantity and length, different day-age silk setting rates, and pollination ear traits. The results showed that the daily silking quantity of corn hybrids showed a trend of rapid to slow increase, and the peak of daily silking length was on the second day of silking. As the number of days of silking increases, the dynamic changes of panicle length, panicle diameter, panicle grain weight, and seed setting rate after pollination were basically increasing first and then decreasing. The peak of panicle diameter appeared on the 4th to 5th day of silking, while the peak of panicle length, panicle grain weight, and seed setting rate all appeared on the 6th to 7th day of silking, with differences among varieties; On the 1st to 4th day of silking, the weight of 100 grains pollinated was higher than that of the control, with bald tips and decreasing day by day. The changes in filament vitality and pollination seed setting rate reflected by the research results have certain reference value in both efficient maize breeding and field production, thus achieving the breeding goal of high yield.

  Summer Millet Varieties for Planting in Kashgar of Xinjiang: Comprehensive Evaluation by DTOPSIS Method Based on Entropy Weight GAO Qiang, ZHANG Yan, LU Zifeng, YAN Qingqing, LI Kangkang, CHEN Runfeng, YANG Yan, XU Lin, ZHOU Wei 2024, 40 (6):  42-47.  DOI: 10.11924/j.issn.1000-6850.casb2023-0313 Abstract + ( 52 )   HTML ( 3 )   PDF ( 1209KB )   ( 7 ) This study aimed to select summer millet varieties suitable for planting in Kashgar of Xinjiang and provide a new comprehensive evaluation method for millet varieties screening. The DTOPSIS method based on entropy weight was applied to comprehensively evaluate 5 millet varieties planted in Kashgar, Xinjiang. 11 characters including yield, growth period, plant height, spike length, grass weight per plant, single spike weight, grain weight per spike, 1000-grain weight, milling ratio, lodging-resistance, Pyricularia setariae were selected for the evaluation. The results showed that the lodging resistance and Pyricularia setariae of millet varieties had great influence on the comprehensive evaluation of millet varieties, and the weights were 0.6191 and 0.2327, respectively. ‘Yugu18’ and ‘Jizajinmiao’ ranked first and second, but the yield of ‘Yugu 18’ was significantly lower than other varieties, ranking last, and ‘Jizajinmiao’ ranked third. ‘Jizajinmiao’ (0.7468) has stable comprehensive traits and good yield of 3906.75 kg/hm2, which is suitable for multiple cropping in Kashgar, Xinjiang, replacing ‘Yugu18’.

  Research on Lodging Resistant Characteristics of Brassica napus L. Variety ‘Qinyou 1618’ ZHANG Zhongxin, WANG Xuefang, ZHANG Yaowen, GUAN Zhoubo, DONG Yuhong, ZHENG Lei, YANG Li 2024, 40 (6):  48-52.  DOI: 10.11924/j.issn.1000-6850.casb2023-0459 Abstract + ( 61 )   HTML ( 3 )   PDF ( 1159KB )   ( 19 ) The aim was to provide theoretical reference for better creating and breeding new germplasm and new varieties of rapeseed with lodging resistance. Taking ‘Qinyou 1618’ and ‘Qinyou 7’ (CK) as the test materials, the strong lodging-resistant characteristics of ‘Qinyou 1618’ were comprehensively analyzed from the aspects of stem characters, plant architectures and root traits. The results showed that the lignin content (20.35%), crude cellulose content (28.19%), and average bending resistance (95.99 N/mm2) of the main stems of ‘Qinyou 1618’ at maturity stage were all extremely significantly higher than those of CK, and the puncture strength (83.1 N/cm2) was significantly higher than that of CK. In particular, the middle and upper parts (60-80 cm) of the main stems had obvious advantages in bending resistance. Meanwhile, ‘Qinyou 1618’ had a more reasonable plant architecture and a more developed root system: suitable plant height (168.5 cm, 11. 6 cm lower than that of CK), lower first-branch height (64.2 cm, 9.9 cm lower than that of CK), higher number of branches (7.2 branches), high rate of stem solidity, longer main inflorescences, higher number of pods; and the root diameters differed significantly from that of CK at the final flowering stage. ‘Qinyou 1618’ has an excellent performance in all of the above-mentioned aspects of lodging resistance, and it is an important direction for breeding new rapeseed varieties with lodging resistance by a comprehensive consideration of stem characters, plant architectures, root traits and other indicators rather than by a single indicator.

  Effects of Optimizing Fertilization Regulation on Agronomic Characters, Yield and Quality of Continuous Cropping Flue-cured Tobacco ZHA Hongbo, ZHAO Fang, LV Jiafeng, GONG Lin, CHEN Hua, GAO Shunbo, WANG Wendong, ZHENG Xingqi, SUN Haochen, ZHANG Bei 2024, 40 (6):  53-56.  DOI: 10.11924/j.issn.1000-6850.casb2023-0355 Abstract + ( 58 )   HTML ( 3 )   PDF ( 1056KB )   ( 7 ) To explore the effects of fertilization on the growth, development, and yield and quality of flue-cured tobacco in different continuous cropping years of tobacco fields in Zhaoyang tobacco area, it was conducted by a small-scale field comparison experiment for optimization fertilization control. The continuous cropping fields of 3, 6, 9 years, and rotation were treated with 30% compound fertilizer + potassium chloride by hole application, 70% compound fertilizer by circular application, and topdressing with potassium nitrate, potassium sulfate and magnesium sulfate in resettling stage. The CK in same field were manured with compound fertilizer by circular + topdressing with potassium nitrate and potassium sulfate in resettling stage. The results showed that the regulation treatment of optimizing fertilization could improve the agronomic traits of tobacco plants in continuous cropping tobacco fields, enhance the resistance of flue-cured tobacco, reduce disease occurrence, increase yield, output value, average price, and proportion of top grade tobacco, and improve the coordination of chemical components in initial flue-cured tobacco leaves.

  ‘Huanghy’ and ‘Jinchui’ Papaya’s Fruits: Storage Quality & Characteristics and Transcriptome Analysis YANG Min, ZHOU Chenping, LI Qingmeng, KUANG Ruibin, WU Xiaming, WEI Yuerong 2024, 40 (6):  57-66.  DOI: 10.11924/j.issn.1000-6850.casb2023-0118 Abstract + ( 60 )   HTML ( 3 )   PDF ( 2128KB )   ( 10 ) To clarify the mechanism of fruit hardness difference among different papaya lines, and provide new ideas for quality control, storage and preservation of postharvest papaya, two superior papaya lines‘Huanghy’ (‘HHY’) and ‘Jinchui’ (‘JC’) with the same genetic background were used as materials. The quality, storage characteristics, and the transcriptome sequencing data of the two lines during storage were observed, counted, and analyzed. The results showed that the water loss rate of ‘HHY’ was higher than that of ‘JC’, and the time of peel shrinkage and pulp cell expansion of ‘HHY’ were earlier than that of ‘JC’. During 12 days of postharvest storage, the fruit hardness of ‘JC’ was significantly higher than that of ‘HHY’. The soluble solids of ‘HHY’ and ‘JC’ reached the peak value on 7th day and 10-12th day of storage, respectively, and both of them had better fruit quality. Transcriptome analysis showed that the differentially expressed genes of ‘HHY’ and ‘JC’ during postharvest storage were obviously enriched in the ethylene pathway, and the ethylene synthesis and signal activation of ‘HHY’ were earlier than ‘JC’. The results of quantitative real-time PCR (qRT-PCR) were consistent with the transcriptome results. The detection result of ethylene content was also consistent with the results of differential gene expression, fruit hardness change and edible time. The ‘JC’ fruit could be softened normally by ethephon treatment. Both ‘HHY’ and ‘JC’ superior papaya lines have better fruit quality. The difference in fruit hardness between the two superior lines is closely related to ethylene signaling pathway. ‘HHY’ is suitable for sale within a week of storage, while ‘JC’ fruit has high hardness, is suitable for long-distance transportation, and has better application potential.

  Status of Carbon Sequestration and Emission Reduction, Influencing Factors and Emission Reduction Measures in Typical Agro-ecosystem in China WANG Jianwei, LI Dongxiao, WANG Hongguang, LI Haoran, WANG Qianyi, ZHANG Mingzhe, LI Ruiqi 2024, 40 (6):  67-74.  DOI: 10.11924/j.issn.1000-6850.casb2023-0242 Abstract + ( 64 )   HTML ( 3 )   PDF ( 1313KB )   ( 53 ) Agro-ecosystem is not only one of the important contributors to greenhouse gases, but also plays an important role in carbon sequestration and emission reduction. Under the background of “CO2 emission peak” and “carbon neutrality”, agro-ecosystem has great potential for carbon sequestration and emission reduction. In this paper, we mainly reviewed the sources, fixed pathways, and influencing factors of main greenhouse gases in China’s typical agro-ecological types. Meantime, the specific contents were discussed including the existing research results, emission reduction potential and existing problems of carbon sequestration and emission reduction in agro-ecosystem. New research directions and exploration approaches were summarized to promote the research in the field of carbon sequestration in the entire agroecological system. It provided an important theoretical reference for China to further carbon sequestration and emission reduction, sustainable development of agriculture, and the realization of the “double carbon” goal as soon as possible.

  Driving Force Analysis and Prediction Simulation of Soil Salinization in Coastal Area of Yellow River Delta ZHAO Ming, CHANG Chunyan, WANG Zhuoran, ZHAO Gengxing 2024, 40 (6):  75-83.  DOI: 10.11924/j.issn.1000-6850.casb2023-0249 Abstract + ( 56 )   HTML ( 3 )   PDF ( 1926KB )   ( 22 ) Understanding the mechanism of soil salinization is an important foundation for the improvement and utilization of saline soil. This paper selects Kenli District, the coastal area of Yellow River Delta, as the study area. First, the influences of 8 factors on soil salinity, including evaporation, precipitation, groundwater burial depth, groundwater mineralization, soil clay content, relative elevation, vegetation coverage and distance from the sea, were analyzed through geographical detectors, and then the main driving forces were screened; subsequently, MLR, PLSR, BPNN and SVM models were constructed, and the most accurate model was selected to construct the soil salt prediction model; finally, under the situation of groundwater changes, three scenarios (a control group, a 0.5 m decrease in groundwater level and a 0.5 m increase in groundwater level) were set up to simulate soil salinity. The factor detection results by the geographical detector showed that the influence of different factors on soil salinity was groundwater salinity>vegetation coverage>groundwater burial depth>distance from the sea>clay content>surface elevation>precipitation>evaporation; the interaction detection results showed that the interaction between groundwater factors, vegetation coverage and distance from the sea had a strong influence. It determined that groundwater mineralization, groundwater depth, vegetation coverage and distance from the sea were the main driving factors for soil salinity; the most accurate prediction model was the BP neural network model, with a modeling set R2 of 0.8847 and RMSE of 1.1350, a validation set R2 of 0.7999 and RMSE of 1.1204; the simulation results of groundwater scenarios showed that appropriately lowering the groundwater level could improve soil salinization. When the water level dropped, the change rates of mild, moderate, and severe saline soil and saline soil were 0.22%, -5.46%, 15.28% and -10.04%, respectively; when the water level rose, the change rates of mild, moderate and severe saline soil and saline soil were -0.02%, -14.77%, 22.51% and -8.02%, respectively. This paper screened out the main driving factors of soil salinity, constructed the best prediction model, and simulated and analyzed the soil salinity according to the set scenarios, providing a basis for the control and prevention of soil salinization in Yellow River Delta.

  The Distribution Characteristics of Soil Temperature at Different Altitudes in Northern Slope Fault Zone of the Middle Tianshan Mountain in Xinjiang GONG Hengrui, ZHENG Yuping, MIAO Yunling 2024, 40 (6):  84-90.  DOI: 10.11924/j.issn.1000-6850.casb2023-0233 Abstract + ( 59 )   HTML ( 3 )   PDF ( 1798KB )   ( 33 ) The study on soil temperature distribution in the whole transition zone from the alpine zone to the edge of Zhungeer Basin in the middle Tianshan fault zone is helpful to understand the characteristics of soil environment in arid area, so as to provide basis for land use and agricultural production. In this paper, the daily observation data of soil temperature at each layer of six meteorological stations in the middle Tianshan fault zone of Xinjiang in 2005 to 2020 were selected. The statistical method was used to analyze the variation characteristics of soil temperature with altitude at different topographies and depths. The results showed that the variation of soil temperature on the northern slope of the middle Tianshan Mountain was enhanced with the decrease of altitude. The annual temperature difference of the highest temperature and lowest temperature in four different terrains was larger in the shallow layer than that in the deep layer, and the occurrence time of the highest temperature in each layer was gradually delayed; in a year, the average daily soil temperature curve at different altitudes of 0-20 cm in the study area was roughly a cosine function curve, and the soil temperature at 320 cm depth was basically a sine function distribution, which was about 3 months later than the maximum and minimum ground temperature of 0-20 cm. The soil temperature in the study area increased first and then decreased with the decrease of altitude. In the range of 3539 to 600 m above sea level, the soil temperature decreased with the increase of altitude. In the range of 600 to 441 m, the soil temperature decreased with the decrease of altitude. 0-20 cm was the active layer of soil temperature change, 40 cm depth of soil temperature could be called the transition layer, 320 cm depth was called the soil temperature stable layer, 80-160 cm was called the soil temperature secondary stable layer.

  Regulation Effect of Biochar on Bacterial Community in Cotton Field Soil under Saline Water Drip Irrigation YE Yang, XIANG Guiqin, GUO Xiaowen, MIN Wei, GUO Huijuan 2024, 40 (6):  91-100.  DOI: 10.11924/j.issn.1000-6850.casb2023-0236 Abstract + ( 52 )   HTML ( 3 )   PDF ( 2063KB )   ( 25 ) To explore the regulation effects of biochar application on soil physicochemical properties and bacterial communities in cotton field soil under long-term saline water irrigation, based on long-term saline water (8.04 dS/m) irrigation, three treatments were set up for field positioning experiments: no nitrogen fertilizer application (N0), nitrogen fertilizer treatment (N360) and biochar combined with nitrogen fertilizer treatment (BC). Determination of soil bacterial community composition was conducted by high-throughput sequencing technology. The results showed that compared with N0 treatment, N360 treatment significantly increased soil electrical conductivity and total nitrogen, but significantly decreased soil pH and available phosphorus content; BC treatment significantly increased soil water content, electrical conductivity, total carbon, total nitrogen and available potassium content. Compared with N0 treatment, N360 and BC decreased the Shannon and Simpson indices of bacterial communities, while N360 treatment increased the Chao 1 and ACE indices. The dominant bacteria at phylum level were Proteobacteria, Acidobacteriota and Actinobacteriota; the dominant bacteria at genus level were Nitrosospira, RB41 and Sphingomonas. N360 treatment increased the relative abundance of Proteobacteria, Acidobacteriota and Firmicutes, but decreased the relative abundance of Actinobacteriota, Gemmatimonadota and Thermoplasmatota; BC treatment increased the relative abundance of Actinobacteriota, Nitrospirota and Chloroflexi, while decreased the relative abundance of Acidobacteriota, Bacteroidota and Verrucomicrobiota. LEfSe analysis showed that both N360 and BC treatments reduced the number of potential biomarkers of bacteria. The RDA results showed a significant correlation between soil bacterial community structure and soil total nitrogen and available potassium content. Nitrogen fertilizer and Biochar combined with nitrogen fertilizer can regulate soil physicochemical properties, thus regulating soil bacterial community structure, which can form dominant species to adapt to salt environment.

  Study on the Application Effect of Leaf Surface Conditioner in Rice Fields with Different Cadmium Pollution Levels LI Cheng, WANG Shaoxi, QIAN Yanjie, YI Zhanping, YAN Xiaobing 2024, 40 (6):  101-106.  DOI: 10.11924/j.issn.1000-6850.casb2023-0240 Abstract + ( 79 )   HTML ( 3 )   PDF ( 1050KB )   ( 10 ) The aims is to explore the effects of three leaf surface conditioners on the total cadmium content, available cadmium content, and soil pH in paddy soil with different levels of cadmium pollution, and on cadmium content in rice, cadmium content in various tissues of rice, and yield. Three leaf conditioners, silicon potassium medium element fertilizer, Bihu Nutritional Package, and Jiangcadulin, were selected to conduct field cadmium control experiments in paddy fields contaminated with heavy metal cadmium in Jinjing Town, Huanghua Town, Chating Town, and Wangcheng District of Changsha County. The results showed that spraying foliar conditioner significantly improved rice yield. Leaf surface conditioners had no significant effect on the total cadmium content in soil, but could significantly reduce the available cadmium content in soil. Leaf surface conditioners can slightly increase soil pH, but their performance varies greatly in different regions. Leaf surface conditioners can reduce the cadmium content of brown rice, but in moderately polluted rice fields, they cannot reduce the cadmium content of brown rice to national standards(≤0.2 mg/kg). Applying Bihu Nutritional Package can increase rice yield, increase soil pH, reduce available cadmium content in soil, and reduce cadmium content in brown rice. It is recommended to further demonstrate and promote this method in lightly and moderately polluted paddy fields.

  Effects of Biogas Slurry and Straw Returning on Soil Nitrogen and Phosphorus Leaching WANG Zhigang, HAN Xue, LIU Yunping, LI Wei, SONG Xiao, GUO Liyue 2024, 40 (6):  107-114.  DOI: 10.11924/j.issn.1000-6850.casb2023-0252 Abstract + ( 53 )   HTML ( 3 )   PDF ( 1267KB )   ( 22 ) To provide theoretical support for agricultural waste utilization and field non-point source pollution prevention, the effects of biogas slurry and straw returning on nitrogen and phosphorus concentration and leaching in soil were studied. The experiment set four treatments of control (CK), conventional N application (CON), optimized N application (OPT) and whole straw manuring plus biogas slurry returning (SMB). The crop yield, soil nitrate residuals and total P leaching were determined for analysis of soil N and P concentration and leaching characteristics. The results showed that crop yield under SMB treatment were reached 99.6% and 95.4%, N and P absorption attained 84.9%, 78.4% and 85.7%, 82.4% than those of CON and OPT treatment, respectively, which N and P agricultural efficiency of SMB treatment was increased by at least 13%. Under SMB treatment, soil nitrate concentration and leaching were decreased by 43% and 77.3% respectively, which the apparent leaching coefficient was 4.83%. The residuals in SMB treatment were 28.9% of chemical N fertilizer application treatment. The P leaching with SMB averaged for 0.045 kg/hm2, and soil inorganic P concentration was 80.7% of chemical P fertilization, which 80% inorganic P converted into Fe-P and Ca-P. Meanwhile, under SMB treatment higher and medium active organic soil P occupied by 55.8%, which was significantly higher than that of conventional P fertilization of 34.2%, indicating biogas slurry and straw returning to filed facilitated various forms of P availability. Thus, straw and biogas slurry returning to field is an environment-friendly waste resource utilization ways in China.

  SNP Molecular Markers: Research and Its Application in Crop Variety Identification TIAN Haiyan, ZHANG Haina, WANG Yongqiang, ZHOU Yongping, ZHANG Yinglu 2024, 40 (6):  115-121.  DOI: 10.11924/j.issn.1000-6850.casb2023-0683 Abstract + ( 60 )   HTML ( 3 )   PDF ( 1131KB )   ( 10 ) Crop variety identification is an important guarantee for breeding and promoting excellent varieties, and the appropriate detection method is the key for the accurate identification of varieties. With the development of molecular marker techniques, the third-generation molecular marker SNP has gradually been applied in the field of variety identification. This paper outlines the characteristics of SNP molecular markers, analyses the features and applicability of five commonly used high-throughput detection methods in crop research, including high resolution melting, competitive allele specific PCR, gene chips, sequencing and genotyping by target sequencing. The research and application of SNP markers in the identification of variety authenticity, purity testing, and analysis of genetic relationships and classification are summarized as well, in order to provide technical reference for subsequent variety identification.

  Bletilla striata Exosomes: Isolation and Apoptosis Protection to Human Immortalized Keratinocyte (Hacat) in vitro SHI Jianyu, LI Huihua, WU Meifang, WANG Wei 2024, 40 (6):  122-127.  DOI: 10.11924/j.issn.1000-6850.casb2023-0207 Abstract + ( 49 )   HTML ( 4 )   PDF ( 1485KB )   ( 17 ) The bioactivity of the exosomes from Bletilla striata (B-exo) on human immortalized keratinocytes (Hacat) in vitro was investigated to provide data for the development of skincare products. The B-exo was extracted by polyethylene glycol precipitation and identified by transmission electron microscopy. The protein concentration was measured by the BCA Protein Assay Kit. Then, the survival rate of Hacat cells, the apoptosis rate and the apoptosis-related pathway proteins were detected by the Cell Counting Kit-8 (CCK8) method, flow cytometry and western blotting, respectively. The B-exo, a double-layer membrane with a teacup-like shape, had an average particle size of 69.63 nm. Each gram of the fresh Bletilla striata contained 5.24E+8 Particles of the B-exo and 19.53 μg protein. The B-exo significantly increased the survival rate of Hacat cells in all treatment groups, compared to the control (P<0.05). The ratios of early, late and total apoptosis induced by H2O2 oxidation were all significantly decreased in Hacat cells after being treated with 10 μg/mL B-exo (P<0.01). In addition, the expressions of Caspase-9 and Caspase-3 protein were significantly increased in the control group, while a decrease was detected in the B-exo treatment. However, the level of BCL-2 protein expression had no difference among the groups (P<0.05). The B-exo isolated by PEG precipitation can promote Hacat cell proliferation and inhibit H2O2-induced apoptosis that is modulated by the changed Caspase-9 and Caspase-3 protein expression in vitro.

  Wild Ganoderma lingzhi Resources in Lianyungang Area: Genetic Diversity and Genetic Relationship Analysis Based on ISSR Markers JI Wei, SU Wenying, LIU Xiaomei, WANG Yipu, REN Likai, XI Xiaoyan, CHEN Kelong 2024, 40 (6):  128-134.  DOI: 10.11924/j.issn.1000-6850.casb2023-0250 Abstract + ( 58 )   HTML ( 3 )   PDF ( 1731KB )   ( 15 ) In order to analyze the genetic relationships and diversity levels of wild Ganoderma lingzhi germplasm resources in Lianyungang area, the genetic diversity and genetic relationship of 15 wild Ganoderma lingzhi in Lianyungang area were analyzed by ISSR molecular markers. The results showed that 40 polymorphic bands were amplified, the fragment size ranging from 250 to 2000 bp, the average allele number was 1.8, the average effective allele number was 1.2454, the average Nei's genetic diversity was 0.1742, and the average Shannon information index was 0.2925. The effective allele number (Ne) ranged from 1.0000 to 1.6423, the genetic diversity of Nei's (He) ranged from 0.1031 to 0.3911, and the Shannon Information index(I) ranged from 0.2235 to 0.5799. According to the genetic clustering diagram of ISSR molecular markers, the similarity coefficient of 15 Ganoderma lingzhi strains ranged from 0.415 to 0.866. When the similarity coefficient is 0.63, the 15 wild Ganoderma lingzhi strains could be divided into four groups. The results provided a reference for the classification, protection and variety creation of Ganoderma lingzhi germplasm resources in Lianyungang area.

  Polyphenol Metabolites During Flue-curing in Tobacco ‘Cuibi NO.1’ Leaves: Dynamic Changes Based on Metabolomics Analysis JIN Liao, LIU Yinsong, LIN Jianfeng, ZHANG Wenwei, GU Gang, WEI Shuwen, WANG Ruiqi, XIE Xiaofang, ZHANG Binghui 2024, 40 (6):  135-142.  DOI: 10.11924/j.issn.1000-6850.casb2023-0289 Abstract + ( 51 )   HTML ( 3 )   PDF ( 3110KB )   ( 15 ) In order to reveal dynamic changes of polyphenol metabolites that influence the modulation characteristics and aroma quality of tobacco leaves during curing process, using the upper leaves of tobacco variety of ‘Cuibi NO.1’ (CB-1) as the material, a total of 15 samples during curing process were collected and analyzed by UPLC-MS/MS. Cluster analysis of the differential metabolites was conducted based on K-means, and the metabolites annotation and metabolic pathway analysis were conducted based on KEGG database. A total of 1069 metabolites were identified from 15 samples, including flavonoids, phenolic acids, lipids, alkaloids, amino acids etc. Notably, 374 of polyphenols were identified, accounting for 34.99% of the total metabolites. The differential metabolites and their K-means cluster analysis showed that most significant changes in metabolite content occurred during the transition from the yellowing stage to the early color-fixing stage. Furthermore, these metabolites were found to be enriched in pathways such as tyrosine metabolism, phenylalanine metabolism, phenylpropanoid biosynthesis, and flavonoid biosynthesis. Additionally, the differential metabolites were found to be enriched in the biosynthesis pathways of hydroquinone, chlorogenic acid, kaempferol, and sinapic acid, which were closely related to tobacco flavor and quality. The dynamic changes of polyphenol metabolites during the tobacco leaf flue-curing process were illuminated based on the metabolomics, and these findings lay a foundation for understanding the material basis of tobacco quality formation and the regulation of tobacco browning.

  Exopolysaccharide Production by Pediococcus acidilactici J1: Fermentation Conditions Optimization YU Wenna, YU Liansheng, WANG Shuo, ZHAO Dan, DU Renpeng 2024, 40 (6):  143-151.  DOI: 10.11924/j.issn.1000-6850.casb2023-0247 Abstract + ( 56 )   HTML ( 4 )   PDF ( 1964KB )   ( 19 ) Lactic acid bacteria (LAB) can synthesize exopolysaccharides (EPS) with various functional characteristics, which can improve the flavor of dairy products and have functions such as anticancer, antioxidant, and probiotic properties. However, the low production of LAB EPS limits its industrial production and application. In order to increase the yield of EPS and promote its commercial development, it is very important to optimize the fermentation conditions of strains producing EPS. In this study, the method of single factor test was used to optimize the conditions for EPS production by Pediococcus acidilactici J1. The results showed that under the conditions of 70 g/L sucrose, 14 g/L beef paste, 3.5 g/L ammonium citrate, 4 g/L anhydrous sodium acetate, 4.00% inoculum amount, 35℃ culture temperature, pH 5.5 and 160 r/min shaking speed, EPS yield was the highest, which was (72.66±0.02) g/L. This study significantly improved the EPS yield of P. acidilactici J1, which was 4.76 times of that before optimization. It laid a solid theoretical foundation for the industrial large-scale production of LAB EPS.

  Species Analysis and Control of Weeds in Tobacco Field in Shaoyang City XIAO Heyou, LIU Congcong, LIU Namei, MA Guanhua, HE Xiangchun, LIU Rong, ZHANG Cixi, YU Qingtao, YAO Tingshan 2024, 40 (6):  152-156.  DOI: 10.11924/j.issn.1000-6850.casb2023-0235 Abstract + ( 68 )   HTML ( 6 )   PDF ( 1167KB )   ( 14 ) In order to control weeds and protect the healthy growth of tobacco effectively in tobacco fields in Shaoyang City, we investigated the weed species. Then, on the basis of the previous optimization of herbicide mixture (fluoroglycofen+sulfosulfuron), the synergistic effect of self-made adjuvant was verified through an investigation of weeding effect 30 days after application. The results showed that there were 42 species of weeds in tobacco fields in Shaoyang City, belonging to 22 families and widely distributed in tobacco fields. The self-made adjuvant mixed herbicides had good weeding effect. After 30 days of application, the total plant control effect of sulfometuron methyl + fluoroglycofen + adjuvant 3000 times solution was 95.44%, the total fresh weight control effect reached 97.19%, and was safe to tobacco. The self-made adjuvant and herbicide mixture can reduce application and promote efficiency, providing reference for effective control of tobacco weeds.

  Experiment of Three-Dimensional Planting and Aquiculture of Peach and Soft-Shelled Turtle ZHU Yan, ZHU Jianming, JIN Yongmin, YUAN Xincheng, JIN Juan, SHI Yonghai 2024, 40 (6):  157-164.  DOI: 10.11924/j.issn.1000-6850.casb2023-0256 Abstract + ( 62 )   HTML ( 4 )   PDF ( 1282KB )   ( 12 ) In order to solve the bottleneck problems of single variety of peach planting, short fruit picking period and large ditch area, a productive experiment of three-dimensional planting and aquiculture of peach and soft-shelled turtle was carried out, the planting and aquiculture system was constructed, the test area was 3.33 hectares, the ratio of planting area to aquiculture area was 9:1. The results showed that aquiculture water quality indexes such as TAN, NO2--N and NO3--N were stable and kept within an ideal range in the three-dimensional planting and aquiculture mode of peach and soft-shelled turtle. COD, TSS, TN and TP were all better, which met the discharge standards of freshwater aquaculture. The pH was slightly alkaline and remained between pH 8.2 and pH 9.5. The yield of peach was 15 t/hm2, and the SSC was 16.2%-19.8%. The survival rate of soft-shelled turtle was 88.83%, the yield of aquiculture area was 1.29 t/hm2, the yield of planting and aquiculture system was 129 kg/hm2, and the income increased by 17900-23000 yuan/hm2. The research indicated that this model of peach and soft-shelled turtle had better water quality indexes, remarkable economic and ecological benefits, which was a kind of model with the advantages of resource recycling, energy saving and environmental protection, high ecological efficiency and high product quality.