Current issue

• 2022 Vol.38 No.25 Published:05 September 2022

  Effects of Nitrogen Application on Root Morphology and Leaf Quality of ‘Hongda’ Flue-cured Tobacco WANG Zheng, LIU Jiuyu, KAN Hongwei, HUANG Shaoli, LI Zhi, DONG Shuchao, LIU Yangxu, LI Xiaoting, YANG Xiaobin, LI Xiancai 2022, 38 (25):  1-7.  DOI: 10.11924/j.issn.1000-6850.casb2021-0882 Abstract + ( 260 )   HTML ( 6 )   PDF ( 1250KB )   ( 103 ) To select a reasonable nitrogen application rate for ‘Hongda’ flue-cured tobacco in Baoshan tobacco-growing area, field experiments were conducted to study the effects of different nitrogen application rates on the growth and development of roots, agronomic traits, economic traits and leaf quality of flue-cured tobacco. The results showed that the maximum leaf width and maximum leaf length of 75 kg/hm2 and 90 kg/hm2 N treatments were significantly higher than those of other treatments, which increased by 21.92% and 18.83%, respectively, compared with those of 45 kg/hm2 N treatment. The total root length, mean root diameter, total root volume, root apical count and root bifurcation count under N treatment of 75 kg/hm2 and 90 kg/hm2 were significantly higher than those under N treatment of 45 kg/hm2 and 60 kg/hm2 at budding stage and after topping. The growth rate of root length was the highest from the growing stage to the budding stage, while the growth rate of root diameter, surface area and total volume were the highest from the resettling growth stage to the vigorous growth stage. The content of total nitrogen and nicotine in the upper tobacco leaves were higher after curing, and the sensory quality of tobacco leaves decreased with the increase of nitrogen application amount. Overall, the comprehensive evaluation of appearance quality and chemical composition coordination of tobacco under nitrogen application rate of 75 kg/hm2 were relatively good, and the comprehensive evaluation of physical properties and sensory quality of tobacco under nitrogen application rate of 45 kg/hm2 were relatively excellent. Considering the growth of flue-cured tobacco and the quality of tobacco leaves, 75 kg/hm2 nitrogen application rate is recommended for ‘Hongda’ in Baoshan tobacco area.

  Green Manure Rotation in Tobacco Field: Effects on the Yield and Quality of Flue-cured Tobacco ZHAO Wenjun, XUE Kaizheng, YANG Jizhou, HU Baowen, FU Libo, YIN Mei, CHEN Jianfeng, WANG Wei, WANG Zhiyuan, WANG Yingxue, LI Yanrun, CHEN Hua 2022, 38 (25):  8-15.  DOI: 10.11924/j.issn.1000-6850.casb2021-0879 Abstract + ( 261 )   HTML ( 7 )   PDF ( 1238KB )   ( 66 ) To evaluate and screen out the best green manure crops suitable for crop rotation with flue-cured tobacco, four treatments were set up in the field test, including flue-cured tobacco and winter fallow, flue-cured tobacco and smooth vetch, flue-cured tobacco and radish and flue-cured tobacco and ryegrass, to explore the yield, output value, agronomic characters, chemical components of flue-cured tobacco and the nutrient content of the tobacco-growing soil. The results showed that different green manure rotations significantly increased the average price and output value of tobacco leaves. Among them, the average price of tobacco leaves in the rotation with smooth vetch, radish and ryegrass was increased by 15.37%, 20.04% and 17.72%, respectively, and the output value was increased by 23.6%, 24.1% and 18.3%, respectively, compared with those of the winter fallow treatment. The smooth vetch treatment increased the proportion of middle and upper class tobacco. The nicotine content, difference between total sugar and reducing sugar and the non-nicotine nitrogen/total nitrogen of the tobacco leaves in the smooth vetch and radish treatments all reached the level of high-quality tobacco leaves. In summary, the planting and utilizing of smooth vetch and radish could significantly increase the average price and output value of flue-cured tobacco, and make the chemical composition of tobacco be more harmonized and the chemical qualities meet the standards of high-quality tobacco. These green manure and flue-cured tobacco rotation systems are the effective methods to be promoted in Yunnan.

  Current Situation and Development Analysis of the Rapeseed Industry in Ningbo JIANG Qi, CHEN Shaojie 2022, 38 (25):  16-19.  DOI: 10.11924/j.issn.1000-6850.casb2021-0802 Abstract + ( 197 )   HTML ( 4 )   PDF ( 1028KB )   ( 59 ) This paper summarized that rapeseed production has large potential in planting area, yield, benefits and market via investigating the current state of rapeseed production in Ningbo. Rapeseed production is mainly restricted by low benefits, low policy support, high risk in planting and low level of industrialized operation. Therefore, countermeasures were put forward, such as promoting the application of new varieties and technologies, increasing policy support, promoting the brand building of local rapeseed oil and developing the diversity of rapeseed planting. These countermeasures will provide technical support for the development of rapeseed industry in Ningbo.

  The Effect of N, P and K Fertilizers on Pakchoi Yield Based on Response Surface Method ZHENG Long 2022, 38 (25):  20-24.  DOI: 10.11924/j.issn.1000-6850.casb2021-0892 Abstract + ( 212 )   HTML ( 5 )   PDF ( 1869KB )   ( 35 ) The study conducted a field fertilization experiment on pakchoi and adopted the response surface analysis method. Through a response surface optimization experiment of three factors and three levels, the study analyzed the effects of nitrogen level (N), phosphate level (P2O5) and potassium level (K2O) on pakchoi yield, then established a quadratic regression equation to analyze the optimal cultivation condition for pakchoi. The results showed that the regression model was significant. The phosphorus level had highly significant effects on pakchoi yield, while nitrogen level and potassium level did not have significant effect. There were significant interactions between the nitrogen level and phosphorus level. There were also obvious interactions between phosphorus level and potassium level. However, the interaction between nitrogen level and potassium level was not significant. The order of yield influencing factors was phosphate fertilizer level> nitrogen fertilizer level> potassium fertilizer level. Through statistical analysis, the optimal cultivation condition is: the nitrogen level of 100.70 kg/hm2, the phosphate level of 98.7 kg/hm2, and the potassium level of 123.2 kg/hm2. Under the optimal condition, the yield of pakchoi is 37.899 t/hm2. The study can provide technical support for the production of pakchoi of high yield and good quality.

  Physiological Regulation Effect of Feather Biodegradation Liquid on Chinese Cabbage Growth in Response to Salt Stress GUO Dongsen, WANG Lin, WEI Qishun, CUI Lianming, ZHOU Ying, GUO Chengbao 2022, 38 (25):  25-29.  DOI: 10.11924/j.issn.1000-6850.casb2021-0893 Abstract + ( 239 )   HTML ( 3 )   PDF ( 1187KB )   ( 70 ) The paper aims to study the application of feather biodegradation liquid (FBL) in alleviating salt stress. Saline soil pot experiment was conducted to analyze the effects of FBL containing different amino acid concentrations (0, 0.1, 0.2, 0.4, 0.8 g/L) on the growth and physiological indexes of Chinese cabbage under salt stress (0.4% NaCl). The results showed that the fresh weight of the aboveground part of Chinese cabbage after root watering FBL was significantly higher than that with no FBL and had no difference with that of CK (no salt treatment). The treatment of 0.4 g/L free amino acid in FBL showed the best growth index. FBL significantly reduced malondialdehyde (MDA) content and significantly increased the activities of peroxidase (POD) and ascorbate peroxidase (APX) in cabbage leaves. Proline concentration increased significantly with the increase of free amino acid concentration in FBL. Soluble protein content increased significantly after FBL application. In conclusion, exogenous FBL can improve the activity of antioxidant enzymes in leaves, increase the content of osmotic regulation substances, and alleviate the damage of salt stress on Chinese cabbage. The optimal free amino acid concentration is 0.4 g/L. The experimental results provide a theoretical basis for the production of Chinese cabbage in secondary salinized soil and saline-alkali land.

  Establishment and Application of Correlation Model Between Chlorophyll Content and SPAD Value in Pepper Under Waterlogging Stress SONG Zhao, LIANG Ludan, HUANG Wenyin, CHEN Xiao, CAO Jian, HE Yuzhi, ZHANG Baige 2022, 38 (25):  30-37.  DOI: 10.11924/j.issn.1000-6850.casb2021-0925 Abstract + ( 189 )   HTML ( 5 )   PDF ( 1404KB )   ( 73 ) The paper aims to explore the correlation between chlorophyll content and SPAD (single-photon avalanche diode) value in pepper under waterlogging stress. In this study, the chlorophyll content of pepper leaves was measured by SPAD and spectrophotometry. The correlation between chlorophyll content and SPAD readings of pepper under waterlogging stress or normal management condition was explored. The results showed that SPAD readings of all varieties were positively correlated with the leaf chlorophyll content of pepper under normal management condition, indicating that SPAD can truly evaluate the chlorophyll content of pepper leaves. The correlation coefficients of the four fitting functions between the chlorophyll content and SPAD in ‘Huifeng No. 2’ were all significantly different. The optimal fitting model was linear equation, and model tests were carried out. Water logging stress seriously interfered with SPAD measurement for pepper chlorophyll content, and there were significant differences in the degree of interference between short-term and long-term stress on different varieties. The optimal mathematical functions of correlation between SPAD reading and chlorophyll content of pepper leaves under normal management or waterlogging stress are established. After significance test, the mathematical model with a significant correlation coefficient can be directly applied to related research. After SPAD value is substituted into the equation, the chlorophyll content can be obtained quickly, which realizes the non-destructive detection of the chlorophyll content in pepper and lays a solid foundation for the rapid measurement of the chlorophyll content in the future.

  Effects of Seedling Containers Made of Camphor Tree Processing Residues on Cucumber Seedling Growth and Physiological Characteristics HE Lei, SUN Enhui, DENG Tao, YONG Cheng, FAN Xiaodong, HUANG Hongying 2022, 38 (25):  38-46.  DOI: 10.11924/j.issn.1000-6850.casb2021-0885 Abstract + ( 179 )   HTML ( 1 )   PDF ( 1777KB )   ( 25 ) To determine the effects of seedling containers made of processing residues of camphor trees on the growth and physiological characteristics of cucumber seedlings, in this study, we analyzed the physical and chemical characteristics, and biodegradable properties of three kinds of containers (SCs) made of different raw materials [processing residues without essential oil extraction (TF-A), processing residues after extracting essential oil (TF-B) and 1:1 blending materials (TF-C)], and measured the containers’ water absorption characteristics’ change and nutrient release regularity. Moreover, we investigated the effects of these SCs on cucumber seed germination, and on the growth physiological indexes and morphology of cucumber seedlings. The results showed that, before reaching adsorption equilibrium, the water absorption rate and swelling rate of water absorption thickness were linearly correlated with the soaking time (R2>0.8521), and the hydrophobicity of the seedling container TF-A was the largest, followed by TF-C and then TF-B. During the culturing period, the total nitrogen release rate in the three kinds of containers was up to 50.23%, the total phosphorus release rate was slightly lower than the rate of total potassium, and the organic carbon mineralization rate had no significant change. The germination potential of the seedlings in TF-B reached 74.81%, and the highest germination rate was 94%, with no significant difference from those in plastic containers (CK). Comparing the seedlings cultivated in TF-C with those in CK, the stem base width, chlorophyll, aboveground fresh weight, underground fresh weight, aboveground dry weight and underground dry weight were increased by 4.59%, 12.18%, 3.01%, 6.80%, 2.86% and 15.79%, respectively, and the seedling index was increased by 23.64%. In general, cucumber seedlings cultivated in containers made of camphor tress processing residues showed good seedling growth characteristics, and had no significant difference from those cultivated in plastic containers. The results indicate that the utilization of camphor tree processing residues as the substrate container has a good application potential in making seedling beds, and the study could expand the utilization way of camphor tree processing residues.

  Genetic Distance and Heterosis of Quantitative Characters of Watermelon WANG Zhiqiang, DU Huiying, LI Cheng, GUO Song, TIAN Mei, YANG Wanbang, YU Rong 2022, 38 (25):  47-51.  DOI: 10.11924/j.issn.1000-6850.casb2021-0857 Abstract + ( 240 )   HTML ( 1 )   PDF ( 1877KB )   ( 40 ) The paper aims to investigate the genetic distance and heterosis of watermelon quantitative characters. 8 watermelon inbred lines were used to make 16 hybrids by NC-Ⅱ, correlation analysis, principal component analysis and heterosis analysis of 7 quantitative characters were conducted. The results showed that fruiting node was significantly and positively correlated with weight per fruit (a<0.05), and soluble solid content at center flesh was extremely significantly and positively correlated with soluble solid content near rind flesh (a<0.01). 7 quantitative characters, including main vine length, fruiting node, weight per fruit, fruit rind thickness, soluble solid content at center flesh, soluble solid content near rind flesh and fruit shape index, were consolidated into three principal components which accounted for 87.3132% of the total variation. The genetic distance of the 8 inbred lines was within 0.3315-1.5121. The intermediate-parent and super-parent heterosis of A02×B04 were better than those of other hybrids and could reach 42.47% and 37.38%, respectively.

  Study on Cultivar Classification of Wisteria According Morphological Characteristics LUO Yulan, ZHANG Guobing, ZHANG Dongmei 2022, 38 (25):  52-59.  DOI: 10.11924/j.issn.1000-6850.casb2021-0875 Abstract + ( 275 )   HTML ( 4 )   PDF ( 1316KB )   ( 34 ) The paper aims to research morphological characteristics and classification grade of Wisteria, formulate the test guidelines for distinctness, uniformity and stability for new varieties of Wisteria. 23 morphological characteristics of 88 Wisteria cultivars were observed, such as branches, leaves, flowers and seeds. The coefficient of variation, correlation and principal components were studied, and UPGMA cluster analysis of cultivars was carried out. The results showed that there were significant differences in 16 morphological characteristics among different cultivars, and the coefficient of variation was 10.66%-126.20%. The coefficient of variation within different species was 0.18%-50.76%, and the degree of variation was as follows: W. floribunda (50.76%), W. macrostachya (24.74%), W. sinensis (23.55%), W. frutescens (21.64%), W. brachybotrys (21.40%), W. × formosa (19.81%) and W. × valderi (0.18%). The 88 cultivars were divided into 4 groups by UPGMA cluster analysis. Each group had certain characteristics and there were differences among the groups. The 23 morphological characteristics reflected the variation of different species or cultivars. Species was the basis for classification of Wisteria cultivars. Flowering period, inflorescence length, flower color, mature leaf color or corolla butterfly shape could be used as important standards for the four-level classification.

  Effects of Melatonin on Seed Germination and Seedling Growth of Astragalus complanatus XIE Fengpu, XU Rongrong, GAO Jing, GUAN Sijing, GE Tiantian, ZHANG Yali, WANG Nan, YAN Yonggang, LI Bo, HUANG Wenjing 2022, 38 (25):  60-71.  DOI: 10.11924/j.issn.1000-6850.casb2020-0713 Abstract + ( 192 )   HTML ( 3 )   PDF ( 3706KB )   ( 43 ) To explore the effects of melatonin on the seed germination and seedling growth of Astragalus complanatus under different temperature, and salt and drought stresses, six melatonin solutions of different concentrations were used to soak the seeds of A. complanatus. The solutions of NaCl and PEG simulating salt and drought environment were used as the experimental groups, respectively, and the distilled water treatment was regarded as the control group. The treated seeds were cultured at 4 different temperatures (15, 20, 25 and 30℃), the germination indicators and seedling growth indicators were measured and calculated after the germination experiment. The results showed that at the same temperature, the total germination percentage of A. complanatus seeds decreased with the increase of drought degree (P<0.05). Under the stresses of salt and drought, the mean germination time at each temperature increased with increasing levels of stress (P<0.05). The length of radicle and cotyledon decreased as the salt stress and drought stress increased at the same temperature. Under the same osmotic potential, the radicle length first increased and then decreased with the increase of temperature. When the stress of -0.7 MPa was at 30℃, the growth of A. complanatus seedlings was inhibited after seed germination under salt stress, while the seeds of some treatment groups did not germinate under drought stress. In this experiment, 25℃ was the optimum temperature for the germination and growth of A. complanatus under salt condition, while 20℃ was the optimum temperature under drought stress. The salt tolerance of A. complanatus was greater than that under drought stress at the same temperature. And as the degree of stress increased, its growth was inhibited. After being treated with melatonin, the effect of stresses on A. complanatus was alleviated to a certain extent.

  Evaluation Methods of Rural Landscape: A Review LI Xiaoying, WANG Zhidong 2022, 38 (25):  72-78.  DOI: 10.11924/j.issn.1000-6850.casb2021-0835 Abstract + ( 440 )   HTML ( 6 )   PDF ( 1181KB )   ( 63 ) With the full implementation of the Rural Revitalization Strategy, the process of rural construction has become the focus of modernization, and the research methods of rural landscape evaluation are becoming more and more diverse. The paper aims to adopt appropriate and effective evaluation methods for different research purposes in practical application, and provide a theoretical basis for rural landscape evaluation. The paper sorts out the research on rural landscape evaluation methods in recent years, and finds that the main research focuses on four aspects: rural landscape aesthetic quality evaluation, rural landscape ecological evaluation, rural landscape characteristic evaluation and rural landscape comprehensive evaluation. The paper also analyzes the specific methods of rural landscape evaluation, as well as the characteristics and applicability of the existing evaluation methods. It summarizes the application characteristics of newly developed techniques, and puts forward the new characteristics of rural landscape evaluation, including interdisciplinary and mutual integration of evaluation methods, quantitative and comprehensive evaluation, landscape information digitization and landscape simulation visualization.

  Resource Distribution, New Species and Isolation Methods of Actinobacteria in Saline-alkali Soil LUO You, XIAO Yang, ZHOU Tingyu, WANG Yue, XIE Chen, LI Dongying, CHEN Xueli 2022, 38 (25):  79-84.  DOI: 10.11924/j.issn.1000-6850.casb2021-0840 Abstract + ( 187 )   HTML ( 4 )   PDF ( 1236KB )   ( 29 ) Saline-alkali soil actinomycetes are highly resistant to stress. They are extremophiles that exist in high-salt and high-alkali areas. Their special physiological mechanisms and diversified metabolites have attracted wide attention in various fields. To effectively study the resources of actinomycetes in saline-alkali soil and their functional genes, it is important to fully understand the diversity of actinomycetes’ species in saline-alkali soil, and then choose the most suitable isolation method. This article summarized the geographical distribution and resource diversity of actinomycetes in saline-alkali soil in China, counted the new species of actinomycetes in saline-alkali soil from 2000 to 2021, summed up the main isolation and screening methods of actinomycetes in saline-alkali soil, and put forward a prospect for the future research work.

  Effects of Amaranthus hypochondriacus Enhanced by Biodegradable Chelating Agent on the Remediation of Cadmium Contaminated Farmland QUAN Shengxiang, SHI Xuefeng, LIU Xiaoyue, LI Changwu, GE Yi, ZHANG Yan 2022, 38 (25):  85-89.  DOI: 10.11924/j.issn.1000-6850.casb2021-0820 Abstract + ( 188 )   HTML ( 1 )   PDF ( 1186KB )   ( 24 ) To provide a theoretical basis and technical support for the remediation of Cd contaminated farmland, the effects of Amaranthus hypochondriacus on the remediation of Cd contaminated farmland were evaluated. The effects of the planting modes of Amaranthus hypochondriacus, as well as the effects of the type, filling amount and filling time of chelating agents on the remediation of Cd contaminated farmland were investigated through field trials. The results showed that based on the analysis of Cd extraction efficiency, the labor cost of planting management, and potential environmental risks of Amaranthus hypochondriacus, the strip sowing mode was better than the direct seeding mode and transplanting mode, and NTA was better than EDDS and citric acid. 85 days after planting Amaranthus hypochondriacus, the remediation efficiency was the best under the application of 450 kg/hm2 NTA. The extraction efficiency of Cd in the aboveground part and underground part of Amaranthus hypochondriacus was 5.4% and 1.2%, respectively. The extraction efficiency of Cd was 6.6% under single-cropping, the relative improvement rate was 40.5%, and the total extraction efficiency was 13.2%. Therefore, the application of biodegradable chelating agent of NTA could effectively improve the remediation efficiency of Cd contaminated farmland by Amaranthus hypochondriacus, and the technology of Amaranthus hypochondriacus enhanced by NTA is a green, economical, efficient and environmental-friendly remediation method for Cd contaminated farmland, which has a broad application prospect.

  The Degradation of Herbicide Atrazine in Soil: Current Research Status SONG Jia, PAN Yan, WANG Xiwei, YU Lihua 2022, 38 (25):  90-95.  DOI: 10.11924/j.issn.1000-6850.casb2021-0846 Abstract + ( 292 )   HTML ( 3 )   PDF ( 1128KB )   ( 61 ) Atrazine, as a herbicide, can cause pollution to soil, groundwater, rivers and lakes while increase crop yield. Although atrazine is less toxic, it affects crop yield and constrains the development of sustainable agriculture in China because it is soluble in water, difficult to degrade and has more residues. This paper summarized the hazards to local flora and fauna caused by excessive atrazine residues, the threat to the ecological environment, and the impact on human health. The adsorption mechanism and residual causes of atrazine were reported, the effects on plants and animals were described. The existing atrazine degradation methods were compared and analyzed, and the future trends of atrazine degradation research were discussed. To solve the problems of long cycle of bioremediation technology, constructive suggestions were put forward in combination with different degradation methods. By combining physical repair technology, bioremediation technology and chemical repair technology, we aim to find out the repair technology that can degrade atrazine residues best and be conducive to the sustainable development.

  Effects of Straw Mulching and Subsoiling on Soil Enzyme Activities in Summer Maize Field GUO Shuya, SHANG Shang, WANG Kun, TANG Qining, ZHANG Yan, FU Guozhan, LU Guangyuan 2022, 38 (25):  96-101.  DOI: 10.11924/j.issn.1000-6850.casb2022-0248 Abstract + ( 164 )   HTML ( 3 )   PDF ( 1107KB )   ( 45 ) The effect of straw mulching and subsoiling on soil enzyme activities in summer maize field was studied. Four conservation tillage modes, including subsoiling and mulching (SS+M), subsoiling and no mulching (SS+NM), no tillage and mulching (NT+M), and no tillage and no mulching (NT+NM), were used to carry out field experiments in Xiping of Henan Province for three consecutive years. The effects of different treatments on the activities of soil urease, soil alkaline phosphatase, soil sucrase and soil catalase were studied. The results showed that the activities of soil urease, soil alkaline phosphatase, soil sucrase and soil catalase decreased with the deepening of soil layer under the four conservation tillage modes. The activities of the four enzymes changed with the change of maize growth period. With the advance of maize growth period, the activities of soil enzymes first increased and then decreased from sowing to 45 days after flowering, the activities of soil urease and soil sucrase reached the maximum at flowering, while the activities of soil alkaline phosphatase and soil catalase reached the maximum at 15 days after flowering. In 0-5 cm and 5-10 cm soil layers, the soil enzyme activities under straw mulching was significantly higher than that without straw mulching, which were in an order of SS+M>NT+M>SS+NM>NT+NM. In 10-20 cm soil layer, soil enzyme activity decreased sharply under NT+M treatment. In 10-20 cm soil layer, soil enzyme activities decreased dramatically under NT+M. In 20-30 cm and 30-40 cm soil layers, the soil enzyme activities of subsoiling treatment was significantly higher than that of no tillage in most periods, which were in an order of SS+M > SS+NM> NT+M > NT+NM. It can be seen that the implementation of straw mulching and subsoiling in the rain fed area of southern Henan could improve soil enzyme activities, which are worthy of popularization.

  Effects of Cassava-Peanut Intercropping Patterns on Soil Fertility LIU Zifan, SU Bimeng, HUANG Jie, WEI Yunxia, XIAO Zili 2022, 38 (25):  102-107.  DOI: 10.11924/j.issn.1000-6850.casb2021-0083 Abstract + ( 238 )   HTML ( 1 )   PDF ( 1284KB )   ( 27 ) To explore the effects of different cassava-peanut intercropping patterns on soil fertility, four treatments were set, which were mono-cropping cassava (MC), one row of cassava intercropping with two rows of peanut (C1P2), two rows of cassava intercropping with three rows of peanut (C2P3) and two rows of cassava intercropping with four of rows peanut (C2P4). A total of 11 soil fertility indexes, such as pH, organic matter, alkali-hydrolyzable nitrogen, available phosphorus, available potassium, sucrase, urease, acid phosphatase, catalase, the number of culturable bacteria and the number of culturable fungi, in the 0-20 cm soil were measured, then the change rate of the 11 soil fertility indexes were assessed comprehensively by the principal component analysis (PCA). The results showed that: (1) the content of soil available P, available K and the number of culturable bacteria of C2P4 were significantly lower than those of MC, the content of soil available P of C1P2 was significantly lower than that of MC, the pH and urease activity of C2P3 were significantly higher than those of MC, while the number of culturable bacteria of C2P3 was significantly lower than that of MC; (2) according to the PCA scores of the comprehensive soil fertility, C1P2 could improve the soil fertility, while C2P3 and C2P4 could decrease the soil fertility. To promote the C2P4 pattern, additional nutrients should be applied to maintain the soil fertility of cassava field for yield increase, thus achieving the sustainable development cassava industry.

  Research Status of Interaction Between Soil Microorganisms and Nematode Communities Under Rotation Mode FAN Yaqi, WANG Yanan, HUO Ruixuan, YAO Tao, YANG Zhenping, QIAO Yuejing, GUO Laichun 2022, 38 (25):  108-113.  DOI: 10.11924/j.issn.1000-6850.casb2021-0859 Abstract + ( 246 )   HTML ( 3 )   PDF ( 1055KB )   ( 44 ) Crop rotation has been used for a long time in China, and the research on crop rotation mode for different cultivation purposes in different regions has been in the process of exploration. Based on the role of rotation in soil ecological improvement, in this paper, the authors analyzed the research on soil nematodes and microbial communities under different rotation modes, discussed the effects of soil physical and chemical properties on them and the correlation of microbial and nematode communities in soil aggregates. The interaction between soil nematodes and microbial communities in the food web of soil ecosystem was analyzed from the macro and micro spatial scales, and the indicative effects of microorganisms and nematodes on soil environment were explored according to their interaction effects, so as to achieve the purpose of reasonable rotation, soil fertility improvement, sustainable and high yield of crops, and to improve farmland soil condition and promote crop growth and development.

  Spatial Characteristics of Farmland Soil Texture and Improvement of Cultivated Land Quality in Hefei GUI Miao, WANG Tiantian, MA Youhua 2022, 38 (25):  114-119.  DOI: 10.11924/j.issn.1000-6850.casb2021-0853 Abstract + ( 258 )   HTML ( 1 )   PDF ( 1663KB )   ( 77 ) To clarify the types of farmland soil texture and texture configuration in Hefei, understand their spatial distribution characteristics in different soil types and administrative regions, and further improve the texture and quality of farmland, based on the data of cultivated land quality monitoring points in Hefei from 2018 to 2020, and combined with Soil Records of each county and district, the spatial characteristics of farmland soil texture and texture configuration in Hefei were analyzed with the support of ArcMap 10.6 software. The results showed that: (1) the cultivated land topsoil texture in Hefei was mainly medium loam soil and heavy loam soil, Chaohu City and Lujiang County had mainly heavy loam soil texture, Feidong County and Feixi County had mainly medium loam soil texture, and the cultivated land topsoil texture was relatively good; (2) the texture configuration of cultivated land in Hefei mainly included upper loose and lower tight type and compact type, the texture configuration of cultivated land in Chaohu City, Feidong County and Feixi County were mainly upper loose and lower tight type, while the texture configuration of cultivated land in Lujiang County and Changfeng County were mainly compact type; (3) to improve the configuration of sandy soil and clayey soil in Hefei, mainly for thin layer type, loose type and upper tight and lower loose type, there are five methods: foreign soil improvement method, organic material backfilling method, mechanical soil improvement method, flood diversion and diffuse siltation method and soil profile reconstruction method. In general, most farmland soils in Hefei are sticky and have good texture configuration ventilation. Targeted improvement measures should be taken for poor texture configuration soils such as sandy clayey soil, so as to improve soil fertility and the quality of cultivated land.

  Response of Signal Molecules and CAT Activities to Aphid in Resistant and Susceptible Tobacco Varieties SUN Jiping, LI Xuejun, SUN Huan 2022, 38 (25):  120-124.  DOI: 10.11924/j.issn.1000-6850.casb2021-0919 Abstract + ( 168 )   HTML ( 2 )   PDF ( 1242KB )   ( 30 ) To study the mechanism of aphid resistance in tobacco varieties, six tobacco varieties with different aphid resistance were selected and inoculated with aphid in pot experiment. The content change of jasmine acid (JA) and nitric oxide (NO), and CAT activities in tobacco leaves were determined 0, 3, 6 and 9 hours after feeding aphid. The results showed that: after being infested by aphids, the JA content in tobacco leaves increased first, peaked at 6 hours and then decreased. The increment of JA content in resistant varieties was higher than that in susceptible varieties. The NO content in leaves of aphid resistant varieties increased first, peaked at 3 hours and then decreased. The difference of the NO content in leaves of susceptible varieties was not significant between 3 hours’ aphid feeding and 0 h, but decreased significantly after 6 hours and 9 hours. The CAT activity of all tested tobacco varieties showed an increasing trend at 9 h, and CAT activity of aphid resistant variety ‘Shubalaomuji2113’ increased the most. Therefore, JA and NO contents and CAT activity could be used as physiological indicators for aphid resistance identification in tobacco varieties. The increase of JA content in leaves 5-6 hours after inoculation could be used to identify the resistance of tobacco varieties to aphids.

  Control Effect of Three Bacillus subtilis Strains on Tobacco Powdery Mildew CAI Yongzhan, WANG Ruibao, BAI Tao, LIU Youcai, HAN Xiaonv, WANG Bin, HUA Xiaobing, LI Cheng, MAO Minglin, ZI Wenlin 2022, 38 (25):  125-129.  DOI: 10.11924/j.issn.1000-6850.casb2021-0817 Abstract + ( 387 )   HTML ( 4 )   PDF ( 1257KB )   ( 43 ) To clarify the control effects of three Bacillus subtilis strains on powdery mildew of flue-cured tobacco variety ‘Yunyan 87’, suspensions, bacterial suspension, and suspension agent (SC) prepared by B. subtilis and low-toxic chemical pesticides were used as test materials to carry out research on their control effects on powdery mildew. The indoor results showed that: YWF-19-0068, YWF-19-0070 and YWF-19-0071 biocontrol agents of 10 times dilution had the control effect of 70.49%, 61.15% and 69.71%, respectively. And 50 times dilution of bacterial suspension agents had the germination inhibition rate on the powdery mildew spore of 56.92%, 56.92% and 58.46%, respectively. The outdoor results showed that: 10 days after the application of the three biocontrol agents at different dosages, the control effects of 50 times dilution of bacterial suspension agents were the best of 46.85%, 65.50%, and 51.70%, respectively. After full and half doses of thiophanate were used once, YWF-19-0070 (SC) was applied once every 3 days. 10 days after the last application, the control effect of the full dosage thiophanate methyl treatment was more than 77.73%, and the control effect of the half dosage thiophanate methyl treatment was more than 60.23%.

  Effects of Different Control Methods on Root-knot Nematode of Greenhouse Cucumber LI Xiaoyan, NI Chang, LIU Xu 2022, 38 (25):  130-133.  DOI: 10.11924/j.issn.1000-6850.casb2021-0834 Abstract + ( 206 )   HTML ( 5 )   PDF ( 1241KB )   ( 76 ) To explore the prevention and control effects of different methods on cucumber root-knot nematode disease, a greenhouse experiment was carried out with the local cucumber varieties as the test materials. The control effects of three methods, including high temperature tightly greenhouse in summer (physical method), application of Bacillus amyloliquefaciens B1619 (biological method) and the integrated control by physical and biological methods, were compared. The results showed that the integrated control by physical and biological methods had the best control effect, reaching 85.17%. This experiment could provide data reference for the harmless prevention and control of greenhouse vegetable root-knot nematode disease in Suqian.

  Comparison of Feeding Performance and Dynamic Changes of Agronomic Characters and Nutritional Components of Six Double-low Rape Lines WANG Honglin, ZUO Yanchun, YAN Xu, ZHOU Xiaokang, KOU Jing, DENG Wuming, XIAO Lian, SONG Xi, DAI Bingbing, YU Qingqing, DU Zhouhe 2022, 38 (25):  134-142.  DOI: 10.11924/j.issn.1000-6850.casb2022-0216 Abstract + ( 345 )   HTML ( 1 )   PDF ( 1393KB )   ( 49 ) The paper aims to select new forage rape varieties suitable for planting in northeast Sichuan. Six new double-low rape lines were used as experimental materials. The biological yield, botanical characteristics, nutritional components, dynamic changes of agronomic characters and nutritional quality during cutting were recorded, and their feeding value was evaluated. The results are as follows. (1) The lines regenerated during cutting at the early flowering stage, and they could be cut twice in the whole growing season, with a cutting interval of 35-37 days. The fresh grass yield was 43.24-50.89 and 13.94-20.03 t/hm2 respectively for the two cutting, the annual fresh grass yield was 57.40-70.46 t/hm2, and the annual hay yield was 6.11-7.28 t/hm2. Among the rape lines, the fresh grass yield of ‘Zhongmianyou 783’ was the highest, which was 70.46 t/hm2 and significantly higher (P<0.05) than that of other test lines. (2) Different rape lines showed significantly different agronomic characters at the first cutting. The plant height of ‘Nanyou 714’ was the highest, up to 162.11 cm; ‘Zhongmianyou 783’ had the largest number of leaves (19.11), and the stem leaf ratio of ‘Nanyou 658 ‘was the lowest, which was 0.91. (3) The crude protein content of ‘Nanyou 12’ was 15.64% at the first cutting, which was significantly higher (P<0.05) than that of other test lines, neutral detergent fiber of ‘Zhongmianyou 783’ was the lowest (25.65%), and acid detergent fiber of ‘13Za768’ was the lowest (20.80%). (4) With the advance of the growth period, the plant height of each line increased gradually, and the plant height did not change in the late pod setting stage. The number of leaves increased first and then decreased, and the number of leaves was the most at the initial flowering stage. The dry matter content and stem leaf ratio increased continuously with the advance of the growth period. (5) The crude protein content of each line decreased with the advance of the growth period, and was the highest at initial flowering stage, which was 12.87%-15.64%. The change trend of neutral detergent fiber and acid detergent fiber were the same, and most of them increased with the advance of the growth period. The content of crude ash decreased with the advance of the growth period. Most of the crude fat increased first and then decreased, and reached the highest at full flowering stage. The feeding value of the first cutting of each rape line was 231.20-262.47, and there was no significant difference (P<0.05) between ‘Zhongmianyou 783’ and ‘13Za768’, but the feeding value of the two lines was significantly higher than (P<0.05) that of other lines. ‘Zhongmianyou 783’ has the best comprehensive performance in the test site and can be popularized and utilized in similar ecological areas.

  Identification and Fermentation Conditions of Syringin-producing Endophytic Fungus CJ7 ZHANG He, YOU Mengyao, WAN Lu, YAN Jiajia, LIU Songmei, ZHENG Chunying 2022, 38 (25):  143-150.  DOI: 10.11924/j.issn.1000-6850.casb2021-0888 Abstract + ( 161 )   HTML ( 4 )   PDF ( 1505KB )   ( 58 ) The paper aims to efficiently utilize endophytic fungi of Acanthopanax senticosus for the production of syringin. The fermentation broth of endophytic fugus CJ7 was analyzed by HPLC with syringin as reference. The antimicrobial activities of CJ7 were examined by agar diffusion. Meanwhile, the fermentation condition of CJ7 was screened by single factor combined with orthogonal experiments, and the endophytic fungus CJ7 was identified by morphological observation and ITS sequence analysis. The results showed that syringin was detected in the fermentation broth of CJ7, and good inhibitory effects of CJ7 on 10 common pathogens were recognized, especially on Staphylococcus aureus. After being optimized, the best culture condition was as follows: 2.5% glucose and 2.0% beef extract fix in PDA culture with initial pH value of 7.0, medium liquid volume of 40% and inoculation amount of 2%. Besides, the fermentation period was 8 d, and the table rotational speed was set at 120r/min. The strain of CJ7 was identified as Aspergillus fumigatus. As a conclusion, the endophytic fungus CJ7 is a syringin-producing one, and the study can lay a foundation for the production of syringin by microbial fermentation.

  Quality Classification of Flue-cured Tobacco Based on HPLC Fingerprint Technique DONG Shiliang, ZHAN Siwen, HE Jiewang, QIU Tong, ZHANG Xueqiong, LIU Fengfeng 2022, 38 (25):  151-157.  DOI: 10.11924/j.issn.1000-6850.casb2021-0948 Abstract + ( 239 )   HTML ( 5 )   PDF ( 1468KB )   ( 76 ) The paper aims to solve the problem of time-consuming and laborious quality classification of flue-cured tobacco. 14 batches of B2F lower limit grade tobacco leaves from typical tobacco leaf producing areas of multiple provinces were analyzed by HPLC fingerprinting technology. Meanwhile, principal component extraction, correlation analysis and cluster analysis were carried out. Based on the first five principal components, there was a significant correlation between potassium and principal component values. Cluster analysis showed that tobacco leaves could be roughly divided into three categories. The difference of potassium content between the first type and the second type of samples was obvious, while the contents of chlorine in the second type of samples were obviously higher than that in the first and third types of samples. The results showed that the HPLC fingerprint of tobacco leaves could be used as a new method for tobacco quality control, which could enhance the efficiency of tobacco quality classification, and reduce the individual differences from artificial evaluation.

  Comparison Analysis of Aromatic Constituents of Jasmine Scented Tea During Orthodox and Isolated Scenting Process LU Jian, WANG Dong, WANG Qun, FU Dejun, WU Dongfen, LIU Yu, ZHU Jianjie, LUO Yaoping 2022, 38 (25):  158-164.  DOI: 10.11924/j.issn.1000-6850.casb2021-0738 Abstract + ( 367 )   HTML ( 3 )   PDF ( 1251KB )   ( 32 ) To explore the effects of scenting technologies on jasmine tea aroma quality, the aromatic constituents of jasmine tea of the orthodox and the isolated scenting process were determined and compared by using HS-SPME/GC-MS/RI method, and the sensory evaluation of the two kinds of processed tea was carried out, in order to lay a foundation for the exploration of new jasmine tea processing technology. The results show that the 6 main aromatic constituents of jasmine tea are linalool, benzyl acetate, α-farnesene, (Z)-3-hexenyl benzoate, methyl anthranilate and indole, and the aromatic characteristics are basically formed after the 1st scenting process. There is little difference of the relative content of alkene during the orthodox and the isolated scenting process. Compared with that of the isolated scenting process, the relative content of alcohols during the orthodox scenting process is 7.75% lower. The relative contents of esters and nitrogenous compounds are both lower during the isolated scenting process. The relative content of ketone is relatively low. According to the sensory evaluation, the aroma score of orthodox scenting tea is higher than that of isolated scenting tea. In conclusion, under the same manufacturing condition, the aroma quality of jasmine tea processed by orthodox scenting is superior to that of isolated scenting.