Current issue

• 2024 Vol.40 No.23 Published:15 August 2024

  Effects of Nitrogen Phosphorus and Potassium Nutrient Management on Winter Wheat Grain Filling Characteristics and Yield under Straw Returning Conditions HAN Mingming, MU Qun, LI Wenqian, CHEN Jun, LV Lianjie, ZHANG Haijun, AN Xia, LI Xiaoyu, CHANG Zhenkai 2024, 40 (23):  1-6.  DOI: 10.11924/j.issn.1000-6850.casb2023-0817 Abstract + ( 110 )   HTML ( 6 )   PDF ( 1371KB )   ( 75 ) To investigate the effects of crop straw returning and nutrient management on the grain filling characteristics and yield of winter wheat, using ‘JM22’ as the test variety, three experimental treatments were set up, T1 was optimized nitrogen, phosphorus, and potassium nutrient management, T2 (CK)was traditional treatment, T3 was crop straw returning nutrient alternative treatment. This study investigated the effects of different experimental treatments on the accumulation and transport of dry matter in winter wheat, grain-filling related parameters, grain yield and economic benefits. The results showed that compared with the control, the T1 treatment significantly increased the allotment amount and contribution rate of dry matter in the grains after anthesis, increased by 43.46% and 20.88% respectively; it also improved the maximum grain filling rate (Gmax) and average grain filling rate (Gmean), with an increase of 17.62% and 3.09% respectively; it also increased the number of grains per ear, thousand-grain weight, and grain yield, by 5.72%, 4.51%, and 12.15% respectively. It is recommended that in areas with similar natural environment and production conditions to this experiment, the optimization of nitrogen, phosphorus and potassium nutrient management is an effective way to take into account both yield and economic benefits.

  Spatiotemporal Patterns of Winter Wheat Water Productivity and Its Decomposition in Western Shandong Plain WU Shulan, REN Pinpin, HOU Shuhai, WANG Shusen, SONG Bailian, HUANG Feng 2024, 40 (23):  7-15.  DOI: 10.11924/j.issn.1000-6850.casb2024-0115 Abstract + ( 90 )   HTML ( 2 )   PDF ( 2022KB )   ( 25 ) Improving crop water productivity (CWP) is an important way to reduce agricultural water use and achieve sustainable development, and mastering the temporal and spatial characteristics of CWP is an important premise to improve CWP by managing production and water consumption. Based on remote sensing evapotranspiration (ET) and agricultural production data, the temporal and spatial patterns of CWP of winter wheat in western Shandong Plain were analyzed, and the contribution of ET and average yield to CWP’s variation was discussed by index decomposition analysis. The results showed that since 2002, the average yield of winter wheat increased significantly (P<0.05) in western Shandong Plain, which promoted the steady increase of the total yield of winter wheat. But after 2010, the contribution of average yield decreased gradually. After 2010, the number of counties with positive effect of planting area (planting area increasing and total yield increasing, or planting area decreasing and total yield decreasing) showed a decreasing trend. After 2006, winter wheat CWP increased significantly (P<0.05) in western Shandong Plain, reaching 1.64 kg/m3 in 2016. The spatial distribution of CWP showed that Dezhou and Jining were the “hot spots” with high CWP. Variation of winter wheat CWP was directly affected by average yield and ET. After 2010, the number of counties with positive effect of average yield (average yield increasing and CWP increasing, or average yield decreasing and CWP decreasing) decreased, and the number of counties with positive effect of ET (ET increasing and CWP decreasing, or ET decreasing and CWP increasing) remained at a high level. It showed that ET played a more important role in the changing of CWP. Under the current situation of flat yield growth, managing ET had become an important way to improve winter wheat CWP in western Shandong Plain, and it was also necessary to further explore the potential of increasing average yield. This study could provide reference for making decision of winter wheat production and water consumption management in western Shandong Plain.

  The Quality Protein Maize ‘Quanyu No.9’: QTL Mapping of Main Nutritional Quality Traits LI Yan, LIANG Zenghao, YANG Rongzhi, LIU Zhitao, TAN Jun, DENG Luchang, CHEN Jie, YANG Lin, HE Wenzhu, ZHU Yonghui, TANG Haitao 2024, 40 (23):  16-21.  DOI: 10.11924/j.issn.1000-6850.casb2023-0889 Abstract + ( 250 )   HTML ( 3 )   PDF ( 1204KB )   ( 26 ) Oil, protein and starch are the main nutritional components of maize kernels, and they are also important quality traits of maize. In order to explore more QTLs related to maize quality, the F2:3 population constructed by quality protein maize 'Quanyu No.9' was used as the material to measure the quality traits in Xindu and Jianyang. QTL analysis was performed using ICIM mapping4.1 software. In this study, a total of 24 QTLs for quality traits were detected in the two locations, of which 9, 9 and 2 QTLs were only associated with oil content, protein content and starch content, respectively, and 4 QTLs were associated with multiple quality traits. These QTLs were distributed on 10 chromosomes, and the phenotypic contribution rate explained by a single QTL was 1.92%-34.43%. The QTL located in Bin7.01 (6399330-8305989) on the chromosome was detectable in both environments, explaining 12.68%-18.13% of phenotypic variation with additive effects. It is the major QTL controlling oil content in corn. This study provides basic data for molecular assisted breeding of maize quality improvement and provides strong support for subsequent breeding practice.

  The Study on Water Consumption Patterns and Influencing Factors of Fresh Corn in Central Yunnan Based on Structural Equation Modeling XUE Yang, LI Youliang, LIU Xiaofang, ZHANG Lei, CHENG Xi 2024, 40 (23):  22-31.  DOI: 10.11924/j.issn.1000-6850.casb2023-0711 Abstract + ( 86 )   HTML ( 2 )   PDF ( 1517KB )   ( 158 ) The study aims to comprehensively understand the water consumption and patterns of the growing period of fresh corn in the Dianzhong Plateau, clarifying the relationship between water consumption and its influencing factors, providing scientific support for the widespread cultivation and irrigation management of fresh corn. The Field irrigation experiments on fresh corn were carried out continuously for 2 years, referencing farmers' planting experience for experimental plots. Automatic weather stations and soil moisture observation devices were installed to collect soil moisture and meteorological data. The dynamics of soil water during the entire growth period of fresh corn, daily water consumption, and crop coefficients were analyzed. The impact of meteorological, soil, and crop factors on water consumption was also studied. It was found that there was significant variation in soil moisture in the 10~30 cm soil layer during the entire growth period of fresh corn. In the later stages of growth, the root system could absorb water from soil layers as deep as 40 cm. The water consumption during the growing season of fresh corn in 2022 and 2023 was 182.32 mm and 175.84 mm, with average water consumption intensities of 2.40 mm/day and 2.31 mm/day, respectively. Water consumption and intensity varied in different years and growth stages. In 2022, the order from highest to lowest was grain filling-milk ripening stage > seedling stage > jointing stage > tasseling stage, while in 2023, it was tasseling stage > grain filling-milk ripening stage > jointing stage > seedling stage. The average Kc values for the entire growth period of fresh corn in the two years were 0.65 and 0.44, with a trend of gradual increase with crop growth, reaching the peak during the grain filling-milk ripening stage. Soil and meteorological factors showed a positive correlation with water consumption, with path coefficients of 0.38 and 0.34, while water consumption and crop growth characteristics exhibited a negative correlation with a path coefficient of -0.46. The water consumption of fresh corn is relatively small and strongly influenced by soil and meteorological factors. The results of this study provide a scientific basis for irrigation quotas and irrigation management of fresh corn in the Dianzhong region.

  Effect of Sowing Period on Growth and Yield of No-till Aerial-Sowing Oilseed Rape WANG Chongming, CHEN Lingying, LU Mingxing, ZHOU Zhihua, TIAN Guisheng, ZHANG Shuiping, ZHENG Zuyun, FANG Qichao, REN Tao, LU Jianwei 2024, 40 (23):  32-38.  DOI: 10.11924/j.issn.1000-6850.casb2023-0728 Abstract + ( 78 )   HTML ( 3 )   PDF ( 1441KB )   ( 35 ) In order to optimize the suitable sowing periods for rapeseed under the no-till aerial-sowing mode, and address the issue of delayed sowing of rapeseed caused by dense stubble in rice-rape cropping system. Three field experiments were conducted during the 2020-2022 oilseed rape season in Wuxue and Huangpi, Hubei Province. Each experiment included eight treatments, with oilseed rape sown 1, 3, 5, 7 d before and after rice harvesting. The impact of varying sowing periods on winter oilseed rape yields, yield components, and growth and development were analyzed. There was a significant difference (P<0.05) in the rapeseed yield between the different sowing periods. The optimal time to sow was 3 d before and 3 d following rice harvesting; this resulted in an average yield increase of 28.3% compared to other sowing times. Density was the main factor affecting rapeseed yield in the pre-harvest rice sowing period, showing an increase with delay in the sowing period (P<0.01). Compared to the 7 d and 5 d before rice harvest sowing treatments, there were an increase of 48.4% in mean maturity density and an increase of 8.2% in pre-winter seedling establishment in the 1 d and 3 d before rice harvest sowing treatments. The primary factor influencing rapeseed yield from post-harvest sowing of rice was the average number of pods per plant, which increased by 15.8% in the 1 d and 3 d post-harvest treatments of rice compared to the 5 d and 7 d post-harvest treatments. The number of pods per plant as well as the number of over wintering green leaves, stem thickness at bud stage, and stem thickness at flowering stage were found to be significantly positively correlated (P<0.05) in different sowing periods following rice harvest. Additionally, the mean over wintering green leaves, stem thickness at bud stage, and stem thickness at flowering stage increased by 18.2%, 12.9%, and 16.0% in the 1 d and 3 d following rice harvest treatments, respectively, compared to the 5 d and 7 d following rice harvest treatments. Sowing seed from three days before to three days after rice harvest can improve aerial-sowing oilseed rape yield by optimizing population structure and promoting individual growth and development. This study offers technical guidance for light and efficient oilseed rape production.

  Effect of 137Cs-γ Irradiation on Seed Germination and Scion Growth in Macadamia Nut TAN Qiujin, ZHOU Chunheng, HUAN Xiuju, XU Peng, ZHONG Jianzhang, HE Xianyang, HUANG Xiyun, YANG Xiaozhou, LIANG Ying 2024, 40 (23):  39-44.  DOI: 10.11924/j.issn.1000-6850.casb2023-0666 Abstract + ( 84 )   HTML ( 3 )   PDF ( 1484KB )   ( 10 ) In order to investigate the mutagenic effect of 137Cs-γirradiation on seeds and scions of macadamia nut. In this study, the seeds and scions form self-bred macadamia variety‘Guire No.1’were treated with 0-250 Gy and 0-200 Gy radiation doses, to analyze the radiation effects on the seed germination, seedling growth and scion survival rate, respectively. The results showed that: (1)137Cs-γhad a very significant inhibitory effect on germination and seedling formation of macadamia nut seeds within a certain dose range. The linear regression equation of radiation dose and germination rate was y=-2.5849x+231.14. The calculated semi-lethal dose and critical dose was 101.895 Gy and 127.744 Gy, respectively. (2) The effect of 150 Gy radiation on the leaf margin spines was significant, and there were fewer leaf margin spines than those of control. With a high dose of 137Cs-γradiation, the phenotypes of treated seedlings leaves became shorter and wider, the plant height became shorter, and the stems became thinner compared with control. (3) Radiation reduced the survival rate of macadamia nut scions, and doses of 100 Gy radiation treatment reduced the survival rate of seedlings to 0. Macadamia nut scions growth well under 10-50 Gy treatment. The results showed that the appropriate dose range of macadamia nut seed and scion were 101.895-127.744 Gy and 10-50 Gy during 137Cs-γradiation mutagenic breeding, respectively. This study provides a certain reference for the application of 137Cs-γ irradiation in the macadamia nut breeding program.

  Effect of Different Soil Modification Materials on the Yield and Quality of Flue-cured Tobacco and the Chemical Properties of Tobacco Planting Soil ZHOU Guoqin, ZHANG Yanhong, WANG Na, WANG Ge, HU Hai, PENG Shengqiang, ZHANG Pengyuan, LI Fuyuan, MU Wenpo, ZHOU Yanbin 2024, 40 (23):  45-52.  DOI: 10.11924/j.issn.1000-6850.casb2023-0794 Abstract + ( 87 )   HTML ( 2 )   PDF ( 1406KB )   ( 38 ) To study the effects of different soil improvement materials on the yield and quality of flue-cured tobacco and the chemical properties of tobacco-planting soil, the relationship between the changes of soil chemical properties and the yield and quality of flue-cured tobacco during the growth and development of flue-cured tobacco was explored to provide theoretical basis and technical support for the production of high-quality tobacco leaves in Luliang tobacco area. In this experiment, ‘Yunyan 121’ was selected as the test variety, and there were 4 treatments (S0: local conventional fertilization treatment; S1: application of lime 60 g/plant; S2: application of biochar 100g/plant; S3: application of earthworm manure 200 g/plant). Through the investigation and analysis of the soil chemical properties, agronomic traits and yield and quality and other aspects of performance of ‘Yunyan 121’ under different treatments, the effects of different soil improvement materials on flue-cured tobacco and tobacco planting soil were comprehensively evaluated. The results showed that the growth of flue-cured tobacco with biochar was the best, followed by earthworm manure. In terms of disease, the incidence of vermicompost application was reduced by 32.49% compared with the control, and the disease index was reduced by 25.2% compared with the control. In terms of soil physical and chemical properties, compared with the control group, the application of biochar significantly increased the content of available potassium in soil and significantly reduced the content of chloride ion in soil. In terms of economic traits, the output value, average price, and proportion of middle and upper tobacco treated with earthworm manure increased by 9.7%, 19.4%, and 13.4%, respectively, compared with the control group. In terms of chemical composition of flue-cured tobacco leaves, the application of biochar had the best coordination effect. The chloride ion content decreased to 0.36 mg/kg, which was 50.7% lower than that of the control group, and the potassium content reached 2.89 mg/kg, which was 16.4% higher than that of the control group. In summary, the application of 100 g/plant biochar contributes to the improvement of tobacco-planting soil, the balance of soil nutrients, the promotion of tobacco plant growth, and the improvement of flue-cured tobacco quality, among which the effect of increasing potassium and reducing chlorine is particularly significant; the application of 200 g/plant earthworm manure could effectively enhance the disease resistance of flue-cured tobacco and improve the economic traits of flue-cured tobacco leaves. Under the conditions of this experiment, the combined application of biochar and earthworm manure for soil improvement can effectively reduce the content of chloride ions in tobacco leaves, improve the quality of tobacco leaves, enhance the chemical coordination of tobacco leaves, and improve economic benefits, which was conducive to pursue highest yield and suitable cultivation.

  Effect of Freeze-thaw Cycles on Distribution of Soil Aggregates and Their Organic Carbon Content in Arable Mollisol ZHU Shuai, LI Shiyong, JIANG Boyu, ZHAO Wenyi, ZHAO Maojie, CHEN Yimin, SUI Yueyu, JIAO Xiaoguang 2024, 40 (23):  53-59.  DOI: 10.11924/j.issn.1000-6850.casb2024-0080 Abstract + ( 96 )   HTML ( 2 )   PDF ( 1206KB )   ( 304 ) To investigate the impact of freeze-thaw cycles on soil aggregates and bound carbon in arable mollisol, this study took arable mollisol in Hailun, Heilongjiang Province as the research object. Incubation experiments were conducted to investigate the impact of freeze-thaw frequency on soil aggregates and organic carbon content of arable mollisol at three temperatures: -9, -18 and -26℃. The results indicated that the content of 1-0.5 mm and 0.25-0.053 mm aggregates exhibited significant changes at all three freeze-thaw temperatures with an increase of freeze-thaw frequencies (P<0.05). Compared with single freeze-thaw cycle, after 17 freeze-thaw cycles at the same temperature, the content of 1-0.5 mm aggregates decreased by 68.53%, 10.91% and 40.96% at -9, -18 and -26℃, respectively. The content of 0.25-0.053 mm aggregates increased by 10.93%, 40.89% and 99.72%, respectively. At -9℃, the fractal dimension of soil aggregates significantly increased (P<0.05) from 2.09 to 2.74, while at -18℃ and -26℃, the changes were small, with changes of 0.1 and 0.05, respectively. The bound carbon of soil aggregates did not show significant changes with the increase of freeze-thaw frequency (P>0.05). At -18℃ and -26℃, the <0.053 mm aggregate showed a gradual decreasing trend, with a decrease of 10.31% and 13.73% after 17 freeze-thaw cycles, respectively. The freeze-thaw impact could significantly reduce the stability of soil aggregates in arable mollisol. The increasing freeze-thaw cycles can significantly reduce the content of aggregates by 1-0.5 mm and increase the content of aggregates by 0.25-0.053 mm(P<0.05). Both freeze-thaw frequency and temperature were important factors affecting the stability of soil aggregates.

  Effect of Plant Coverage on the Diversity and Community Structure of Soil Fungi in Banana Cropping System ZHANG Wenlong, WANG Yongfen, XU Shengtao, YANG Limei, ZHOU Yunfan, LI Xundong, ZHENG Sijun 2024, 40 (23):  60-67.  DOI: 10.11924/j.issn.1000-6850.casb2023-0758 Abstract + ( 89 )   HTML ( 1 )   PDF ( 2594KB )   ( 163 ) Due to unreasonable agricultural practices, soil degradation in banana cropping system is becoming more and more serious, which restricts the healthy and sustainable development of banana industry in China. Plant coverage could improve soil physical and chemical properties and optimize soil microbial community structure, which is an important farming practice to improve soil degradation in agricultural ecosystems. In this study, through the wide-narrow row planting method, the traditional planting method with bare soil was used as control, cultivated saritro [Macroptilium atropurpureum (DC.) Urb.] and natural weeds in wide rows were used as plant coverage treatments. With continuous positioning experiments, based on the high-throughput sequencing of the collected soil samples, the differences in soil fungal diversity and community structure were analyzed with plant coverage treatments under banana cropping system, which would explore the sustainable utilization of soil in banana production. The results showed that there were significant differences in the composition of fungal communities under different plant coverage treatments in banana cropping system, and showed an increasing trend with the continuous of plant coverage. According to the function prediction of FUNguild, compared with the bare soil control, the Saprotroph Symbiotroph guilds in 2019 and 2020 increased significantly (P≤0.05), and the fungal community of Pathogen Saprotroph guilds in 2020 decreased significantly (P≤0.05). The results of co-occurrence network analysis showed that compared with the bare soil control, the community complexity was no difference in the plant coverage treatments, but the community stability was higher. However, the differences in the core microorganisms reflected that saritro treatment reduced the dominance of Fusarium ASV, which would reduce the risk of occurrence of soil-borne disease Fusarium wilt in banana. Saritro treatment effectively increased the symbiotic beneficial fungal guilds, reduced the potential pathogenic fungal guilds, which was beneficial to maintain soil health in banana cropping system. The planting mode combining wide and narrow rows with inter-row cover plants could effectively improve soil microbial diversity, which is conducive to sustainable development of banana industry.

  Overview of Glyphosate and Research Progress in Microbial Degradation GE Zhijian, YANG Fengshan, LI Kun, FU Haiyan, LIU Chunguang 2024, 40 (23):  68-74.  DOI: 10.11924/j.issn.1000-6850.casb2024-0200 Abstract + ( 111 )   HTML ( 2 )   PDF ( 1175KB )   ( 414 ) The herbicide glyphosate is widely used in agriculture because of its high efficiency and low cost, but it also poses certain harm. This paper provided a brief introduction to glyphosate toxicity and mechanism. It was clarified that the harm of glyphosate to water environment was mainly in the aspects of affecting water quality, aquatic organisms and ecosystems. The harm to soil was mainly reflected in the destruction of soil microbial ecology, the destruction of soil microbial community structure and function, and the influence of soil enzyme activity. The research progress of bioremediation of glyphosate-contaminated soil was introduced. The bioremediation of glyphosate-contaminated soil was mainly microbial degradation methods. Compared with non-biodegradation such as adsorption and photolysis, microbial degradation was more environmentally friendly, efficient and promising. Finally, the microbial degradation methods of glyphosate contaminated soil remediation were prospected, in order to provide reference for the application and improvement of glyphosate microbial degradation technology in glyphosate contaminated soil.

  Preliminary Study on Effect of Cadmium Contaminated in Paddy Fields of Karst Mining Area In-situ Remediation ZHAO Ru, SHAO Guosheng, HU Junming, JIANG Xin, LIU Shun'ao, LI Tingting, WEI Xianghua, LIU Chao 2024, 40 (23):  75-80.  DOI: 10.11924/j.issn.1000-6850.casb2023-0804 Abstract + ( 81 )   HTML ( 1 )   PDF ( 1266KB )   ( 13 ) There is an urgent need for cadmium pollution transfer risk and soil nutrient restoration technology in rice field in karst mining area of South China. To explore the effect of nutritional passivator on cadmium (Cd) contaminated paddy soil in mining areas, and to clarify its effect on the morphological transformation, bioavailability and soil quality of cadmium in the rhizosphere soil of rice, the in-situ remediation experiment of paddy soil was carried out. Three treatments were set up, including no passivator (T1), inorganic nutritional passivator (T2) and organic-inorganic nutritional passivator (T3). The gradient diffusion film (DGT) technique was used to study the bioavailability of Cd and Cd transformation in rhizosphere soil of the paddy field, and the biological correlation between Cd transformation, bioavailability of Cd and soil quality was evaluated in rhizosphere soil of the paddy field. The results showed that: (1) nutritional passivator affected the ratio of cadmium formation in cadmium-contaminated paddy soil. Nutritional passivator could promote the transformation of exchangeable cadmium to residual cadmium in soil. Nutritional passivator reduced the proportion of exchangeable cadmium content. Compared with T1 (control), the T2 and T3 decreased the proportion of exchangeable cadmium content in soil by 14.71% and 5.88%, respectively. Nutritional passivator increased the proportion of reducible cadmium content. Compared with T1 (control), the T2 and T3 increased the proportion of reducible cadmium content in soil by 8.51% and 6.38%, respectively. Nutritional passivator increased the proportion of residual cadmium content. Compared with T1 (control), the T2 increased the proportion of residual cadmium content in soil by 10%, T3 had no obvious changes. (2) The bioavailability of Cd in rhizosphere soil of Cd-polluted paddy fields was reduced by treatment with nutritional passivator. Compared with T1 (control), the T2 and T3 treatments decreased bioavailability significantly by 54.21% and 50.47% at harvest stages. (3) Nutritional passivator improved soil quality in soil of Cd-polluted paddy fields. Compared with T1 (control), the T2 and T3 increased soil organic matter, pH and cation exchange capacity by 7.37%, 7.50% and 5.29%, 17.06% and 12.24%, 11.10%, respectively. Nutritional passivator could restore polluted soil and improve soil quality synchronously.

  Calculation and Trend Prediction of Carbon Emissions from Planting Industry in Guangdong Province CHU Xialing, YE Gaosong, ZHENG Linxiu 2024, 40 (23):  81-91.  DOI: 10.11924/j.issn.1000-6850.casb2023-0796 Abstract + ( 85 )   HTML ( 0 )   PDF ( 1674KB )   ( 12 ) The study aims to clarify the carbon emission characteristics of planting industry in Guangdong Province and its decoupling status from agricultural economic growth, predict the carbon emission trend from 2022 to 2060, and provide theoretical basis for the formulation of agricultural carbon emission reduction and sink increase policies in Guangdong Province. Using the carbon emission coefficient method of IPCC (Intergovernmental Panel on Climate Change), this paper calculated the carbon emissions, carbon sinks, net carbon emissions, carbon emission intensity, and net carbon emission intensity of the planting industry in Guangdong Province from 1990 to 2021, based on two major types of carbon sources of agricultural material inputs and farmland soil utilization, then analyzed their dynamic evolution trends. The decoupling relationship between carbon emissions and agricultural economic growth was discussed by the Tapio decoupling model, the carbon emissions and net carbon emissions from 2022 to 2060 were predicted as well by the Grey prediction model GM (1, 1). The results showed that: (1) from 1990 to 2021, the total amount and net amount of carbon emissions of planting industry in Guangdong Province both showed fluctuating downward trend, with decrease of 25.23% and 30.58%, respectively. The carbon emissions from farmland soil utilization accounted for 63.94% to 79.69%, while the carbon emissions from agricultural material inputs accounted for 20.31% to 36.06%. Fertilizer, pesticides and agricultural film were the top three sources of carbon emissions from agricultural inputs, while rice planting and vegetable planting were the main sources of carbon emissions from farmland soil utilization. (2) From 1990 to 2021, the carbon sink decreased in fluctuation, with decrease of 22.23%. The carbon sink mainly came from rice, sugarcane, and vegetables plants, with the proportion of 87.23%-94.03%. (3) From 1990 to 2021, the carbon emission intensity and net carbon emission intensity in Guangdong Province measured by agricultural output value, significantly decreased by 93.20% and 93.69%, respectively. (4) The decoupling statuses were dominated by weak decoupling and strong decoupling, indicating good coordination between agricultural economic growth and carbon emissions from planting industry. (5) Using the data from 1991 to 2021, 2001 to 2021, 2011 to 2021 as samples for prediction, respectively, it was found that the carbon emissions and net carbon emissions of planting industry in Guangdong Province would both show continuous decreasing trend after 2022, but the reduction amplitude values were different. The prediction value of carbon emissions using the data from 2011 to 2021 as samples was the smallest and the reduction amplitude was the largest. Based on the above conclusions, this paper put forward relevant policy recommendations such as continuously implementing measures to reduce the amount and increase the efficiency of fertilizers, pesticides, and agricultural films, optimizing rice field management, and strengthening scientific and technological support for green and low-carbon agricultural development.

  Effects of Urease and Nitrification Inhibitor and Coated Urea on Soil Nutrients Content and Sunflower Yield in Hetao Irrigation Area MIAO Yuncai, HE Tiehu, LIU Deyan, DING Weixin 2024, 40 (23):  92-98.  DOI: 10.11924/j.issn.1000-6850.casb2023-0806 Abstract + ( 78 )   HTML ( 2 )   PDF ( 1197KB )   ( 11 ) The effects of urease and nitrification inhibitor, and coated urea on soil nutrients and sunflower yield were evaluated in the Hetao Irrigation Area. An in-situ field experiment was established and six treatments with four replicates were set up, including no fertilization (Control), conventional N application (NPK), NPK plus urease inhibitor HQ and nitrification inhibitor DCD (HDN), NPK plus urease inhibitor NBPT and nitrification inhibitor DCD (NDN), 50% urea plus 50% coated urea (PCU1), and 30% urea plus 70% coated urea (PCU2). The results indicated that compared to the NPK treatment, HDN and NDN treatments significantly increased soil organic carbon (SOC), total nitrogen (TN), available phosphorus (AP), available potassium (AK) and inorganic nitrogen (IN) content by 2.4%-5.0%, 11.6%-12.1%, 36.7%-50.0%, 12.4%-13.2% and 24.0%-56.6%, respectively. In contrast, application of partial substitution of urea with coated urea did not affect SOC, TN, AP, AK and IN content. HDN and NDN treatments also increased soil dissolved organic carbon (DOC) content by 7.3% to 10.2%, while the application of coated urea did not have any effects on DOC content. Aboveground biomass (AGB) of sunflower was increased in HDN, NDN and PCU1 treatments when compared to the NPK treatment, in which HDN treatment resulted in the highest AGB. Compared to the NPK treatment, the HDN, NDN and PCU1 treatments significantly increased sunflower yield and nitrogen use efficiency, with the highest increase observed in the HDN treatment. In contrast, PCU2 treatment had no significant effect on sunflower yield and reduced nitrogen use efficiency. The application of conventional urea in combination with urease and nitrification inhibitor is a crucial management practice for enhancing soil nutrient retention capacity and sunflower yield in Hetao Irrigation District.

  Spatiotemporal Variation of Climate Resources and Meteorological Disasters of Facility Agriculture in Henan Province TAN Yanjing, LI Hui, ZHANG Xihe 2024, 40 (23):  99-104.  DOI: 10.11924/j.issn.1000-6850.casb2023-0390 Abstract + ( 102 )   HTML ( 2 )   PDF ( 1982KB )   ( 24 ) Based on the daily meteorological data of 95 meteorological stations in Henan Province from 1961 to 2020, the spatiotemporal variation characteristics of the climate resources and major agrometeorological disasters of facility agriculture were analyzed by using the methods of climate tendency rate and the Matlab and ArcGIS software. The results showed that the average temperature and the average minimum temperature in the growing season of facility agriculture in Henan Province showed a significant increasing trend, while the sunshine hours showed a significant decreasing trend. The spatial distribution showed a zonal distribution. The average temperature and the average minimum temperature increased from north to south, while the sunshine hours decreased from north to south. The number of low temperature stations with the daily average temperature < - 8℃ had a significant decreasing trend, and the number of sunshine days had a significant increasing trend, with the number of snowstorm stations no obvious trend of change. The days of low temperature decreased from north to south, while the days of sparse sunlight increased from north to south, with the spatial distribution of snowstorm days implicit. Arrangements on planning of facility agriculture should be done in Henan Province, because of the diversity of agricultural meteorological disasters.

  Characteristics of Drought Changes in Shaanxi Apple Production Area over Last 60 Years Based on Standardized Precipitation Evapotranspiration Index ZHANG Yong, HUANG Junfang, LIU Lu, ZHANG Weimin, QU Zhenjiang, LIANG Yi 2024, 40 (23):  105-117.  DOI: 10.11924/j.issn.1000-6850.casb2023-0767 Abstract + ( 91 )   HTML ( 1 )   PDF ( 2584KB )   ( 38 ) The aim of the research is to clarify the characteristics of drought changes in Shaanxi apple producing areas under the background of climate warming, and provide reference for Shaanxi apple production area to adapt to climate change and scientifically guide drought prevention and damage reduction. Using the monthly precipitation and temperature data from meteorological stations in apple-producing areas in Shaanxi Province over the past 60 years, the standardized precipitation evapotranspiration index (SPEI) for each growing season and stage in Shaanxi apple-producing areas was calculated, and its trend, abrupt change, and periodic variation were analyzed. The research results show that the annual precipitation in the apple-producing areas of Shaanxi has been significantly decreasing over the past 60 years, with a general trend towards aridity during the growing season. The mutation points were mainly concentrated in the 1970s and 1990s, with a more pronounced arid trend after the 1990s. Among them, the eastern Weibei apple-producing area was particularly affected, with an increasing risk of aridity. The period from bud formation to early fruiting stage shows a clear arid trend and an increasing risk of aridity. The mutation points were mostly concentrated in the late 1970s to early 1980s and early 1990s. After the early 1990s, the arid trend had become more apparent, especially in the western and eastern Weibei and Guanzhong producing areas. The coloring-ripening period and winter dormancy period show an overall arid trend, with most mutation points concentrated in the 1970s. Since the mid-to-late 1970s, there had been an arid trend, but the change was not significant in all producing areas. The fruit enlargement period mainly fluctuated without a significant trend. The drought analysis based on SPEI combines rainfall and evapotranspiration, considers longer time scales, and is applicable to different climatic regions, providing a more objective reflection of drought conditions in the apple-producing areas of Shaanxi Province under the background of climate warming. The main influencing factors leading to drought in this region are the decrease of precipitation and the increase of temperature caused by climate change.

  Paenibacillus polymyxa Identification and Its Antibacterial Effect on Pyricularia oryzae DOU Longtao, QU Xiaojun, HU Jihua, JIANG Wei, TIAN Yuan, YAN Gengxuan, ZHANG Shumei 2024, 40 (23):  118-125.  DOI: 10.11924/j.issn.1000-6850.casb2023-0723 Abstract + ( 88 )   HTML ( 1 )   PDF ( 3891KB )   ( 570 ) In order to broaden the resources of microbial biocontrol agents and to develop biocontrol strains with high efficacy in the control of Pyricularia oryzae, the present study was conducted to screen a strain KH-19 with a good antagonistic effect from the inter-root soil of rice. The strain was identified by morphological observation, physiological and biochemical tests, and 16S rDNA sequencing. The inhibitory activity was determined by the oxford cup method and the plate stand-off method. The effectiveness of the strain was tested against P. oryzae in pots. The results showed that the KH-19 strain was Paenibacillus polymyxa, which had bacteriostatic effects on three strains of Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Pectobacterium carotovorum BC2, and also had good antagonistic effects on other six pathogenic bacteria and eight pathogenic fungi, and its inhibition rate reached 63.67% against P. oryzae. The results of the pot test showed that the disease index of P. oryzae decreased with the increase of the concentration of P. polymyxa KH-19, and the disease index of P. polymyxa on the 20th day of inoculation reached 78.11% when the concentration of the bacterial suspension was 106-107 cfu/mL. The results showed that P. polymyxa KH-19 had potential application value as a biocontrol strain with broad-spectrum inhibitory activity against P. oryzae.

  The Biocontrol Strain GDND-2 of Tobacco Fusarium Root Rot: Identification and Control Effect SHEN Huifang, YANG Qiyun, ZHANG Jingxin, PU Xiaoming, SUN Dayuan, LIU Pingping, LIN Birun 2024, 40 (23):  126-134.  DOI: 10.11924/j.issn.1000-6850.casb2022-0746 Abstract + ( 88 )   HTML ( 2 )   PDF ( 2159KB )   ( 461 ) The study was to reserve resources for the development of new biocontrol agents to control tobacco Fusarium root rot. The antagonistic strains were screened against Fusarium oxysporum, and were identified throgh morphological, biochemical characteristics and molecular technique. The tolerance of the antagonistic strain was determined by plate scribing method, and its control effect on tobacco root rot was verified by potting experiment. The antagonistic strain GDND-2 was screened. Its fermentation filtrate had a strong inhibitory effect on mycelium growth of F. oxysporium, the inhibition rates of 10% and 20% fermentation filtrate were 53.09% and 62.24%. The strain GDND-2 was identified as Bacillus velenzensis. It presented a broad inhibitory spectrum, and showed strong tolerance to extreme temperature, acid-alkali and salt. It was not sensitive to seven commonly used fungicides such as carbendazim. The control effects of fermentation broth of GDND-2 on tobacco root rot were 70.00%, 74.62% and 79.51% on the 15th, 30th and 45th day after root drenching, and its control effect on the 45th day was higher than carbendazim. Bacillus velenzensis GDND-2 with excellent traits and broad inhibitory spectrum could effectively control tobacco Fusarium root rot, and it is expected to be developed as a biocontrol agent.

  Leaf Neoplasia Pathogen on Euryale ferox: Biological Characteristics and Fungicide Screening LI Meixia, WANG Xiaofei, CHEN Yali, QIAN Xin, ZHOU Changyong, FU Yousheng, CAO Kaige, LIU Weizhong 2024, 40 (23):  135-142.  DOI: 10.11924/j.issn.1000-6850.casb2023-0654 Abstract + ( 79 )   HTML ( 0 )   PDF ( 1522KB )   ( 114 ) Leaf neoplasia was one of the important diseases affecting aquatic vegetables such as Euryale ferox. To clarify the optimal conditions for the preservation of the pathogen causing Euryale ferox leaf neoplasia, a method based on the rate of mycelial growth was employed to investigate the effect of the temperature, pH, carbon source and nitrogen source on the growth of the pathogen's mycelial. To screen out fungicides for the control of this disease, laboratory toxicity tests were conducted to determine the inhibitory rate of single and mixed fungicides against the pathogen, followed by field efficacy trails to assess the control effects of single fungicides on Euryale ferox leaf neoplasia. The results indicated that the optimal temperature for mycelial growth was 30℃, and the most favorable pH 7. The preferred carbon and nitrogen sources were glucose and ammonium nitrate, respectively. The laboratory toxicity assays revealed that the EC50 values for the tested fungicides against the pathogen were 0.8992 mg/L for tebuconazole, 0.6531 mg/L for pyraclostrobin, 0.1650 mg/L for prothioconazole, 1.8751 mg/L for difenoconazole, 0.9227 mg/L for epoxiconazol, 2.3432 mg/L for propiconazole, and 6.0517 mg/L for azoxystrobin. Among these, tebuconazole, pyraclostrobin and prothioconazole exhibited strong inhibitory activities. The field efficacy trials demonstrated that the control effect of tebuconazole, pyraclostrobin and prothioconazole against Euryale ferox leaf neoplasia were 94.36%, 85.64%, and 82.56%, respectively. In door joint toxicities test, tebuconazole and pyraclostrobin were combined in a ratio of 1:1, 1:2, 1:3, 1:4, 1:5, 5:1, 4:1, 3:1 and 2:1 by weight. The combination of 5:1 showed synergistic effect, with the synergistic ratio (SR) of 1.5029, indicating that this formulation could be effectively used for the control of Euryale ferox leaf neoplasia in agricultural practices.

  Control Ability of Three Species Ladybird Beetles on Frankliniella occidentalis and Bemisia tabaci ZHANG Huan, HE Hengguo, LIU Guo, YU Jiamin, LIU Dongyang, DENG Quan, LI Sihan, ZHANG Peixu, YONG Yanping, WU Xinglong, XIAO Kejun, PU Deqiang 2024, 40 (23):  143-147.  DOI: 10.11924/j.issn.1000-6850.casb2023-0803 Abstract + ( 77 )   HTML ( 1 )   PDF ( 1175KB )   ( 28 ) The aim is to clarify the biological control potential of three dominant natural enemies, Hippodamia variegata, Coccinella septempunctata L. and Megalocaria dilatata, against Frankliniella occidentalis and Bemisia tabaci. Under indoor conditions, three species of ladybugs were fed with different benefit-to-harm ratios using field collected F. occidentalis and B. tabaci nymphs, the density of F. occidentalis and the number of B. tabaci nymphs with feeding marks was recorded, as well as the proportion of their adults that had emerged, for each treatment during the experiment. The results showed that after 3 days of feeding and treatment of F. occidentalis, the control ability of the three adult ladybugs and larvae on F. occidentalis was: adults of H. variegata>third instar larvae of C. septempunctata L.>adults of C. septempunctata L.>third instar larvae of M. dilatate> third instar larvae of larvae of H. variegata> adults of M. dilatata, among which the adult H. variegata had the highest control effect on F. occidentalis, reaching 48.35%. After 3 days of feeding and treatment of B. tabaci nymphs, the number of bite marks of young nymphs in the third-instar larvae treatment group of M. dilatata was 2.61%, which was significantly higher than that in the control group, and there was no significant difference between the other treatments. There was no significant difference in the adult plumbing rate of B.tabaci between the treatment groups. This study showed that the adults of H. variegata had a high control effect on F. occidentalis, and the third instar larvae of M. dilatate had a certain feeding tendency against the young nymphs of B. tabaci nymphs, and the three kinds of ladybirds did not have feeding tendency to the old nymphs of B. tabaci nymphs.

  Isolation and Identification of A Porcine Staphylococcus aureus and Drug Sensitivity Test ZHANG Xin, ZHAO Donghui, LI Jie, JIA Weijuan, LIU Zhilin, JIA Zelin, CUI Jiayu, WANG Xueli 2024, 40 (23):  148-152.  DOI: 10.11924/j.issn.1000-6850.casb2023-0765 Abstract + ( 84 )   HTML ( 1 )   PDF ( 1635KB )   ( 72 ) This study aims to investigate a strain of pathogenic bacteria, isolated from the organs of dead pigs on a Jinzhou pig farm. The research encompasses bacterial isolation and identification, drug sensitivity tests, and clinical diagnosis and treatment implications. Gram staining was conducted using LB agar culture, followed by BP special medium culture. Drug sensitivity testing, 16S rDNA sequencing, and mouse pathogenicity testing were also performed. Pathological tissue sections were prepared for microscopic observation. Gram staining microscopy results indicated that the bacterium was Gram-positive cocci. The BP Petri dish revealed black colony growth with a transparent ring around it. Drug sensitivity tests demonstrated high sensitivity to enrofloxacin, ofloxacin, amikacin, and kanamycin. 16S rDNA sequencing revealed a high similarity between the 16S rDNA fragments of this bacterium and Staphylococcus aureus. Microscopic examination of pathological sections revealed significant pathological damage in various tissues and organs. The causative organism on this pig farm was identified as Staphylococcus aureus, which exhibited resistance to certain antibiotics and demonstrated some pathogenicity in the mouse attack test.

  The Prevention and Control Effect of Ethanol Extract from Agrimonia pilosa on Highly Pathogenic Vibrio Infection in Litopenaeus vannamei LIAO Sheguo, LAI Fuxiang, LIU Didi, ZHENG Hongchao, ZHENG Ran, LIN Kangqi, FAN Lanfen 2024, 40 (23):  153-164.  DOI: 10.11924/j.issn.1000-6850.casb2023-0800 Abstract + ( 120 )   HTML ( 2 )   PDF ( 2688KB )   ( 604 ) In order to investigate the preventive and therapeutic effects of the alcohol extract of Herba Agrimoniae on highly pathogenic Vibrio, this study analyzed the gut microbial, immune related genes and intestinal tissue of Litopenaeus vannamei infected with highly pathogenic Vibrio after feeding with 90% alcohol extract of Herba Agrimoniae for 3, 6, and 9 days. The results showed that the variety and number of bacteria in the intestines of sick shrimp increased. Among them, the number of pathogenic bacteria such as Shewanella, Vibrio and Spongiimonas were significantly higher than that of healthy shrimp, and the composition of the flora was significantly different from that of healthy shrimp. The relative abundance of the above pathogenic bacteria groups decreased significantly, while Lysobacter, a beneficial bacteria group, increased significantly. In addition, the alcohol extract of Herba Agrimoniae can increase the expression of immune related genes TLR, ALF, Crustin, and HSP70 in shrimp, protecting the intestinal tissue of shrimp. It was concluded that the addition of alcohol extract from Agrimonia pilosa to the feed could significantly improve the immunity of shrimp after infection with highly pathogenic Vibrio and enhance the antibacterial ability of shrimp.