Current issue

• 2020 Vol.36 No.13 Published:05 May 2020

  Effects of Bio-organic Fertilizer on Rice Yield and Soil Fertility Qiu Yao, Liu Bei, He Lin, Yang Meiyu, Tan Shiyong 2020, 36 (13):  1-5.  DOI: 10.11924/j.issn.1000-6850.casb19020032 Abstract + ( 609 )   HTML ( 25 )   PDF ( 1266KB )   ( 224 ) Field plot experiments were conducted to study the effects of bio-organic fertilizer on rice growth, carbon and nitrogen metabolism, rice yield and soil fertility. The results showed that the application of bio-organic fertilizer could promote the growth of rice, improve its agronomic traits, increase biomass and carbon and nitrogen metabolic capability, enhance root activity, and raise rice yield and fertility of cultivated land; bio-organic fertilizer contained a large number of organic matter and functional microorganisms, which could reduce soil bulk density and increase the number of bacteria, fungi and actinomycetes in soil. Soil bulk density was negatively correlated with the number of microbial communities, and the correlation coefficient with bacteria, fungi and actinomycetes was -0.96, -0.94 and -0.97, respectively. Soil organic matter content was positively correlated with the number of microbial communities, and the correlation coefficient with bacteria, fungi and actinomycetes was 0.83, 0.90 and 0.85, respectively. The correlation coefficient between soil organic matter content and rice yield was 0.85.

  Phosphorus Fertilizer and Soil Types: Effects on Rice Seedling Quality Liu Ziqi, Niu Shiwei 2020, 36 (13):  6-10.  DOI: 10.11924/j.issn.1000-6850.casb19010057 Abstract + ( 420 )   HTML ( 7 )   PDF ( 1279KB )   ( 128 ) To find out the effects of phosphorus fertilizer content and soil type on rice seedling quality, root morphology and nutrient uptake, taking the mid-late maturing variety ‘Liaojing 401’ as the test material, we chose 3 soil types: loamy soil, clay soil and sandy soil, and studied the effects of 6 phosphorus fertilizer and soil type combinations on rice seedling quality by using the method of split block experiment. The results showed that: the rice seedlings cultivated by low-phosphorus clay and high-phosphorus clay had the best quality and root morphology, which was more conducive to the growth of seedlings; the phosphorus fertilizer amount of 2.5 g/pot could meet the rice absorption of phosphorus fertilizer, indicating that the proper amount of phosphorus fertilizer is helpful to cultivate robust seedlings.

  Research Progress of Potato Drip Irrigation System Yang Hu, Zhuang Wenhua, Tian Xiaoqin, Li Zhuo, Liu Chao, Qu Huijuan 2020, 36 (13):  11-16.  DOI: 10.11924/j.issn.1000-6850.casb19030041 Abstract + ( 372 )   HTML ( 9 )   PDF ( 1202KB )   ( 403 ) The study aims to provide reference for academic researchers in the field of potato drip irrigation research. It starts from the law of potato water demand, summarizes the effects of different irrigation systems on potato growth and photosynthesis under drip irrigation condition, and on potato yield and quality. It is found that the conclusions of potato research are not accurate and lack of timeliness, and the drip irrigation technology and agronomic cultivation techniques are not perfect in most areas. It is proposed that future research can start from the simulation of potato water consumption rules and quality under different irrigation systems, precision agriculture and potato yield and cost.

  High-yield Combination of Hybrid Rapeseed: Grey Relational Analysis of Yield and Agronomic Characters Li Yanlan, Yang Jincheng, Li Xiang, Liu Jianjian, Wang Jingqiao, An Zhengyun, Cai Shujiang, Hu Xinzhou, Li Hongyan 2020, 36 (13):  17-22.  DOI: 10.11924/j.issn.1000-6850.casb19020053 Abstract + ( 365 )   HTML ( 19 )   PDF ( 1230KB )   ( 66 ) To study the effect of agronomic characters on rapeseed yield when high yield is obtained by heterosis combination in rapeseed breeding, 11 agronomic characters of 15 hybrid high-yield combination materials are analyzed by grey relational degree analysis method. The results showed that the order of correlation from close to far between yield and main agronomic characters of hybrid high-yield combination rapeseed was 1000-grain weight> planting density > growth period> number of effective siliqua in the main inflorescence> main inflorescence valid length> pod density> average number of pods and grains> plant height> number of effective branches at one time> number of effective siliqua per plant> height of branches. In the high-yield breeding of hybrid combination rapeseed in Yuxi of Yunnan, under the premise of suitable close planting, the sowing density could be moderately increased, and early sowing could be conducted. When the plant type is appropriate, it is necessary to strengthen the breeding of several characters such as 1000-grain weight, the number of effective siliqua in the main inflorescence, and the effective length of the main inflorescence.

  Evaluation and Screening of Salt Tolerance of Sugar Beet Germplasm Resources at Seedling Stage Zhang Ziqiang, Bai Chen, Zhang Huizhong, Li Xiaodong, Fu Zengjuan, Zhao Shangmin, E Yuanyuan, Zhang Hui, Wang Liang, Zhang Bizhou 2020, 36 (13):  23-28.  DOI: 10.11924/j.issn.1000-6850.casb19020002 Abstract + ( 459 )   HTML ( 5 )   PDF ( 1239KB )   ( 77 ) To screen out sugar beet varieties with high salt tolerance, 33 sugar beet seedlings were cultured in nutrient solution and treated with salt stress. The salt tolerance of these germplasm resources at seedling stage was evaluated comprehensively by comparing the root length and plant height of these materials and control seedlings. The results showed that: (1) salt stress had the greatest effect on the root of sugar beet seedlings, the smallest effect on SPAD value, and had the general effect on plant height, fresh weight of plant and fresh weight of shoot. (2) 33 materials were eventually classified into three categories: the first was salt-resistant materials, including 19 materials such as ‘54338’, ‘FLORES’, ‘44581’; the second was salt-sensitive materials, including 6 materials such as ‘52212-1’, ‘2928’and ‘54303’; and the third was salt-resistant materials, including 8 materials such as ‘44176’, ‘28010’ and ‘KUHN1387’. It provided material basis for the research of salt tolerance treatment and salt tolerance breeding of sugar beet in the future.

  Effects of N, P, K Rates on Yield and Quality of Flue-cured Tobacco Variety ‘Xiangyan 5’ Wang Xichun, Yuan Fang, Zhou Xiangping, Yang Quanliu, Xiao Qinzhi, Huang Shiwang, Jiang Duzhong, Gao Chunyang, Tang Shen, Lu Chaojun 2020, 36 (13):  29-35.  DOI: 10.11924/j.issn.1000-6850.casb19020070 Abstract + ( 472 )   HTML ( 3 )   PDF ( 1263KB )   ( 107 ) The objective of this study is to investigate the effects of N, P, K rates on yield and quality of flue-cured tobacco variety ‘Xiangyan 5’ and to provide a scientific basis for further extension of ‘Xiangyan 5’ in Yongzhou. An orthogonal L9(3 4) design with three N level, three P level and three K level were employed for the field experiment. Agronomic attributes, major economical characters, and quality of tobacco ‘Xiangyan 5’ were investigated of different treatments. The results showed that the different treatments of yield, value, average price, tobacco leaf grade ratio existed difference. Among all the treatment, N135P108K378 had better economic characters and better economic efficiency, the flue-cured leaves ratio of sugar alkali ratio, nitrogen alkali ratio, potassium chlorine ratio were suitable, the internal chemical components of tobacco leaves were more coordinated. Applying NPK at the rate of N:P:K=135:108:378 could get the best effect of flue-cured tobacco variety ‘Xiangyan 5’ under medium soil fertility in the tobacco region of Yongzhou.

  BvM14-Dof3.4 Gene in Sugar Beet M14 Line: Cloning and Expression in Response to Salt Stress Ma Chunquan, Huang Yuanyuan, Li Haiying 2020, 36 (13):  36-41.  DOI: 10.11924/j.issn.1000-6850.casb20191200897 Abstract + ( 418 )   HTML ( 10 )   PDF ( 1679KB )   ( 103 ) The objective is to study the function of BvM14-Dof3.4 gene in response to salt stress. The full-length sequence of BvM14-Dof3.4 gene from the root of sugar beet M14 line was obtained by PCR and analyzed by bioinformatics. The response mode of BvM14-Dof3.4 gene under salt stress was also verified. The results showed that the largest ORF of the gene was 408 bp which encoded 135 amino acids, the molecular weight of the protein was 12646.63 Da, the theoretical pI was 4.68, the protein was hydrophilic protein; the secondary and tertiary structure of the protein were mainly composed of extension chain and random curl; the amino acid sequence similarity between BvM14-Dof3.4 and Dof3.4 from Beta vulgaris database was up to 99.26%. The phylogenetic tree showed that BvM14-Dof3.4 protein was highly homologous with Dof3.4 protein from Spinacia oleracea. According to the transcriptome database from the root of sugar beet M14 line under salt stress, BvM14-Dof3.4 gene was involved in the response to salt stress, which was up-regulated by 2.05 times under 200 mmol/L NaCl and 1.41 times under 400 mmol/L NaCl. The full cDNA length of BvM14-Dof3.4 gene was successfully obtained in this experiment and its response to salt stress was determined. The results have certain significance for the exploration of high quality genes in sugar beet M14 line and the improvement of stress resistance of cultivated sugar beet, and lay a foundation for further research on the function of BvM14-Dof 3.4 gene in response to salt stress.

  Effect of Different Nursery Substrates on Seedling Rate and Growth of Aegiceras corniculatum in Freshwater Irrigation Ding Yuelian, Tan Jiade, Chen Jie, Wan Lixin, Li Xin 2020, 36 (13):  42-47.  DOI: 10.11924/j.issn.1000-6850.casb19010135 Abstract + ( 393 )   HTML ( 3 )   PDF ( 1258KB )   ( 385 ) To explore the artificial cultivation technology of Aegiceras corniculatum in freshwater and to select suitable substrates for seedling culture, using pond mud, yellow soil, river sand and coconut bran as experimental materials, 10 kinds of mixed substrates were combined by different ratios, and the seedling culture was carried out. The results showed that different mixed substrates had obvious effects on seedling rate, seedling height, ground diameter, root growth, fresh weight and dry weight. Among them, the total score of substrate F (30% pond mud+ 50% yellow soil+ 10% river sand+ 10% coconut bran) was the highest. Cultured by this substrate, the average seedling height, ground diameter, main root length, number of the first-order lateral roots, whole plant biomass, and seedling rate of Aegiceras corniculatum was higher than those of the mixed substrate with the lowest score by 24.3%, 11.1%, 6.3%, 6.5%, 37.5%, and 2.0%, respectively.

  Effects of Soil Moisture on the Growth and Evapotranspiration of Amygdalus pedunculata Zhao Xin, Zhu Chao, Zhai Sheng, Tian Xiaofei, Zhang Qingxin, Xin Yifan, Sun Shuchen 2020, 36 (13):  48-52.  DOI: 10.11924/j.issn.1000-6850.casb19030130 Abstract + ( 389 )   HTML ( 4 )   PDF ( 1299KB )   ( 79 ) Using Amygdalus pedunculata 1-year-old seedlings, we studied the growth and evapotranspiration characteristics of A. pedunculata under water stress with three soil water content levels: CK (optimal soil water content, 75%-100% of the field capacity), mild drought stress (50%-75% of the field capacity) and waterlogging stress (100%-125% of the field capacity). The results showed that evapotranspiration decreased with the increase of drought stress and drought stress had a significant effect on the growth and evapotranspiration of A. pedunculata. The plant height, branch diameter, leaf area and number of new branches of A. pedunculata increased under mild drought stress, but the leaf senescence was also fast. Waterlogging stress was conducive to the growth of leaf area and branch diameter and could slow down the leaf senescence, but it was not good for the increase of plant height and number of new branches. The comprehensive analysis showed that mild drought stress was the most suitable soil moisture content for the growth of A. pedunculata seedlings.

  A Comparative Study on the Photosynthetic Characteristics Among Cerasus humilis Varieties in Arid Areas Yao Ze, Jiang Shengxiu, Yan Zizhu, Wu Hao, Liu Guangwu 2020, 36 (13):  53-58.  DOI: 10.11924/j.issn.1000-6850.casb19030108 Abstract + ( 330 )   HTML ( 1 )   PDF ( 1246KB )   ( 79 ) Study on leaf morphology and photosynthetic characteristics of Cerasus humilis among different varieties in the northwest arid region can provide a basis for the selection of high yield, high quality and water-saving varieties. To clarify the morphological and photosynthetic characteristics of leaves and their correlation among different kinds of C. humilis, the photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr) and intercellular CO2 concentration (Ci) and leaf area were measured by Li-6400 photosynthesis system. The results showed that: (1) there were significant differences in leaf length and leaf width among different C. humilis varieties, the leaf area was ‘Nongda No.5’> ‘Nongda No.7’> ‘Nongda No.6’> ‘ecological late maturing’> ‘ecological early maturing’; (2) the net photosynthetic rate and transpiration rate of ‘Nongda No.7’ were the highest, of which, the net photosynthetic rate was significantly higher than that of ‘Nongda No.6’ and ecological early maturing, and the transpiration rate were significantly higher than that of other varieties, the stomatal conductance and intercellular CO2 concentration of the five C. humilis varieties had no significant difference; (3) the correlations among net photosynthesis rate, stomata conductance, transpiration rate and leaf area were highly and significantly positive, and the correlation between intercellular CO2 concentration and leaf area was highly and significantly negative; (4) the correlations among net photosynthesis rate, stomatal conductance, transpiration rate, leaf vapor pressure deficit and leaf temperature were highly and significantly positive, and the correlation between net photosynthesis rate and intercellular CO2 concentration was highly and significantly negative.

  Effect of Biochar Amendment Levels on the Yield and Quality of Chinese Cabbage and Garlic Zhou Jiashun, Yu Hongxi, Yang Jie, Sun Wenqing, Gao Wenwen, Zhong Yamin, Shi Yujie 2020, 36 (13):  59-64.  DOI: 10.11924/j.issn.1000-6850.casb19010145 Abstract + ( 413 )   HTML ( 2 )   PDF ( 1193KB )   ( 238 ) The current study investigated the effect of different levels of biochar amendment on soil quality, and vegetable yield and quality, aiming to explore the optimum biochar application level on Chinese cabbage and garlic, and providing a basis for biochar application on vegetable. A pot experiment was conducted, and four levels of the biochar were added into soil including: CK (no biochar), C1 (1%), C2 (2%) and C3 (3%), with five repeats. For soil properties, biochar amendment significantly increased soil organic carbon by 23.86%-93.54%; 3% of biochar amendment increased soil nitrogen content by 11.33% and 23.09% during the growth season of Chinese cabbage and garlic, respectively; soil available phosphorus and available potassium content were increased by 18.77%-80.04% and 80.19%-396.18%; and biochar also increased soil pH value. For crop productivity, biochar amendment increased the aboveground fresh and dry weight of Chinese cabbage by 60.11%-86.11% and 57.89%-76.32%. And 3% biochar amendment increased garlic aboveground fresh biomass, dry biomass and belowground dry biomass by 36.89%, 32.00% and 61.56%, respectively. For vegetable quality, 2% and 3% biochar amendment increased the soluble protein content of Chinese cabbage by 9.07% and 9.37%; while the soluble sugar and nitrate content of Chinese cabbage was decreased by 6.72%-7.00% and 38.62%-93.20%; 2% and 3% biochar amendment increased the soluble protein content of garlic by 9.83% and 9.56%, while 3% treatment decreased garlic soluble sugar and nitrate content by 17.98% and 39.27%. The application of biochar on Chinese cabbage and garlic planting can improve soil fertility, and raise vegetable yield and quality simultaneously. And the optimum biochar application level for Chinese cabbage and garlic are 1% and 3%.

  Effects of Ridge Direction and Ridge Spacing on Growth, Yield and Quality of Tomato in Early Spring Zhao Wei, Jiang Liyuan, Tang Lei, Zhang Feng, Yang Zhaosen, Chen Zhijie 2020, 36 (13):  65-68.  DOI: 10.11924/j.issn.1000-6850.casb19020019 Abstract + ( 573 )   HTML ( 6 )   PDF ( 1187KB )   ( 52 ) To improve the light efficiency of greenhouse tomatoes, ‘Xirun2007’ was used to study the effects of ridge direction and ridge distance on the growth, yield and quality of tomatoes by setting up two ridge directions (east-west ridge directions and magnetic south by west 14 degrees ridge directions) and three ridge distances (1.2, 1.4 and 1.6 meters). The results showed that the plant height increased with the increase of ridge spacing at 55 days after transplanting. The plant height of magnetic south by west 14 degrees ridge directions and 1.6 m ridge spacing treatment (P1.6 m) and east-west ridge directions and 1.6 m ridge spacing treatments (1.6 m) was significantly higher than that of other treatments. When the ridge spacing was 1.6 m and 1.4 m, the number of tomato flower panicles increased significantly in the magnetic south by west 14 degrees ridge directions compared with that in the east-west ridge direction. With the increase of ridge spacing, the yield of tomato decreased. The yield of tomato treated with P1.2 m was 13.3 kg/m 2, and the lowest yield of tomato treated with P1.6 m and 1.6 m was 8.4 kg/m 2 and 8.3 kg/m 2, respectively. With the increase of ridge spacing, sugar content in tomato fruit and fresh weight of stem and leaf per plant increased. Considering the tomato plants growth, yield, quality and other factors, in this study area suitable ridge distance is 1.2 meters and ridge direction is magnetic south by west 14 degrees ridge direction for early spring tomato cultivation.

  Nutritional Components of the Shoots of Facility Cultivated Aralia thomsonii Wang Qiaoli, Li Shengxing, Zhu Qiurong, Li Heqing, Shi Zhuogong 2020, 36 (13):  69-74.  DOI: 10.11924/j.issn.1000-6850.casb19030008 Abstract + ( 481 )   HTML ( 3 )   PDF ( 1354KB )   ( 76 ) To grasp the variation of nutritional components of shoots of Aralia thomsonii under facility cultivation in summer, this paper studies the contents of mineral elements, amino acids and sugar acids in different months of the same year and the same period in different years. The results showed that the shoots of A. thomsonii harvested in facilities contained abundant nutrients. Amino acid content was the highest in June (17.46%). The contents of sugar, acid and vitamin C were the highest in July, with 1.59% of sugar and acid and 9.00 mg/100 g of vitamin C. The content of mineral elements was the highest in September, which was 8024.32 mg/kg. Through comparing and analyzing nutritional components in four different months, it was found that in September, the content of nutrients in the shoots of A. thomsonii was relatively high and the nutrients were balanced. As to the nutritional components in the same period in different years, in September 2014, the nutritional value was relatively high and the nutrition was relatively balanced with SRC value of amino acids of 95.36, the content of sugar and acid of 1.02%, and vitamin C of 4.7 mg/100 g, while the content of mineral elements was the highest in September 2018 (7670.32 mg/kg).

  Flowering Biological Characteristics of Male Sterile Wild Tea Plants Jiang Huibing, Yang Shengmei, Sun Yunnan, Chen Linbo, Tang Yichun 2020, 36 (13):  75-81.  DOI: 10.11924/j.issn.1000-6850.casb19020011 Abstract + ( 405 )   HTML ( 2 )   PDF ( 2491KB )   ( 146 ) To study the flowering biological characteristics of male sterility in wild tea plants, and reveal the phenotypic characteristics, taking the male sterile plants and fertile plants of wild tea as materials, we observed the flowering phenology, single-flower development process and flower morphological characteristics of wild tea plants in field, and measured the pollen viability and stigma receptivity by the methods of in vitro germination and staining. The results showed that: the flowering phase of male sterile plants of wild tea lasted for 29-33 days from early September to early October, the flowering phenology was similar to that of the control material; there were 107 days from bud germination to withering of male sterile flowers, 14 days longer than the control material; male sterile flowers had the typical characteristics of male-sterile, such as low corolla development degree, bent and deformed filaments, adhered and shriveled anthers, anthers unable to release pollen or release aborted pollen; female organs of male sterile flowers developed normally in wild tea plants, the stigma receptivity were from 1 day before flowering to 4 days after flowering, the best pollination time was 1 day after flowering. The investigated male sterile wild tea plants belong to the types of anther abortion and pollen abortion.

  Cultivation, Breeding and Post-harvest Management of Crocus sativus: Recent Progress Zhou Lin, Yang Liuyan, Li Qingzhu, Zhang Xue, Zhang Yongchun 2020, 36 (13):  82-88.  DOI: 10.11924/j.issn.1000-6850.casb20191100866 Abstract + ( 408 )   HTML ( 4 )   PDF ( 1232KB )   ( 124 ) To improve the yield and quality of saffron in China, we analyzed the studies on mother bulbs size, buds number, cultivation mode, cultivation density and depth, fertilization methods and types, disease control, flowering regulation, tissue culture rapid propagation and detoxification, genetic breeding, filament processing and storage, and summarized the research progress of cultivation, breeding and postharvest management of saffron. We pointed out that China lacks the standard classification of saffron bulbs, and the specifications of high-yield and high-quality production techniques. The bottlenecks in the production and breeding of saffron should be solved from three aspects: field cultivation, flowering regulation and variety selection. The production technology of saffron should be regulated to ensure the quality of saffron medicinal materials and promote the development of saffron industry.

  Study on the Seed Germination and Tissue Culture of Rosa graciliflora Li Huiling, Luo Yulan, Zhang Zhang, Yin Lijuan, Li Pujin, Zhang Dongmei 2020, 36 (13):  89-93.  DOI: 10.11924/j.issn.1000-6850.casb19030046 Abstract + ( 426 )   HTML ( 1 )   PDF ( 1608KB )   ( 52 ) This research aims to obtain a complete plant of Rosa graciliflora and establish its rapid propagation system. Germination rate of R. graciliflora seed was observed on different cold stratification time. Meanwhile, tender stem segments were used as explants to investigate the effects of different sterilized reagents, sterilized time and phytohormone combinations on the axillary bud induction and proliferation rate, and also rooting rate. Furthermore, the culture medium was optimized for each growth stage. The results showed that the seed germination rate was as high as 35% when treated by sand storage in low temperature for 9 months. The optimum combination for stem sterilization was 10% sodium hypochlorite solution for 15 min followed by 0.05% mercuric chloride solution for 10 min, and the optimal medium for bud proliferation was 1/2MS+NAA 0.2 mg/L+6-BA 2.0 mg/L. The rooting rate reached 90% in the rooting medium of WPM+IBA 0.3 mg/L. In conclusion, this research explores the seed germination condition of R. graciliflora and establishes its rapid propagation system, which could lay a foundation for the industrial production and further utilization of R. graciliflora.

  Wild Plant Resources in Weihe River: Investigation, Development and Utilization Huang Yaling, Lu Zhigang, He Tao, Lv Xiaofan, Wang Zirui, Li Houhua 2020, 36 (13):  94-102.  DOI: 10.11924/j.issn.1000-6850.casb19010140 Abstract + ( 353 )   HTML ( 7 )   PDF ( 2096KB )   ( 1053 ) The wild plant resources in Weihe river were used as the research objects, and their species, distribution, ornamental and ecological characteristics were investigated and analyzed, aiming to protect and explore local wild plant resources by a scientific way, and providing references for the plant selection and protection in the process of ecological restoration, thus to promote the process of ecological restoration and wetland conservation in Weihe river even the Yellow river. The results showed that Weihe river was rich in wild plants resources, 453 species of wild plants belonging to 93 families and 310 genera were found. According to the distribution, 88 species of plants were screened out. There were 4 species of trees, 10 species of shrubs and 74 species of herbs among of them. The selected plants had broad application potential in landscape, ecological restoration and medicinal use. In the progress of ecological construction projects in Weihe river, it is beneficial to the building of ecological garden city when the selected plants were used as part of the landscape design. The economic and ecological value would be achieved simultaneously via exploring their medical value. In view of the plants development and utilization value and based on the local condition in Weihe river, we proposed suggestions as protecting and exploring the resources in combination with landscape application, strengthening the ecological benefit study and so on.

  Diversity Analysis of Agronomic Traits of Wild Tea Plants in Mountain Emei Liu Dongna, Li Lanying, Gong Xuejiao, Luo Fan, Wang Qin 2020, 36 (13):  103-109.  DOI: 10.11924/j.issn.1000-6850.casb19030061 Abstract + ( 360 )   HTML ( 3 )   PDF ( 1155KB )   ( 200 ) To explore excellent resources of wild tea plants and population species, the genetic diversity analysis and resource evaluation of 40 wild tea germplasms in Mountain Emei were carried out by using factor analysis, clustering analysis and sensory evaluation methods. The results show that tea germplasms in Mountain Emei are abundant, and mostly shrub type. The coefficients of 18 morphological traits range from 7.70% to 60.99%, and the biggest coefficient variation is young shoot color of 60.99%. Factor analysis shows that the six main factors of 18 morphological traits account for 80.74% of total contribution rate, whose representative indices are leaf size, leaf serrate and leaf surface characteristics. Clustering analysis divides the materials into five groups, showing complex genetic relationships and rich genetic diversity. Green tea processing properties of the 11 germplasms preliminarily screened perform well, and the total score of sensory evaluation is above 92, the products have aroma of fresh fragrance of flowers, or high and long fragrance of flowers, or chestnut fragrance with floral aroma, and its taste is fresh, or sweet, or full-bodied and mellow.

  Pb Pollution in Sediments of the Bijiang Watershed of Yunnan: Distribution Characteristics and Evaluation Han Yunchang, Zhang Naiming, Bao Li, Yang Muqing 2020, 36 (13):  110-114.  DOI: 10.11924/j.issn.1000-6850.casb19010029 Abstract + ( 385 )   HTML ( 1 )   PDF ( 1635KB )   ( 44 ) The paper aims to understand the distribution of Pb in the sediments of the Bijiang watershed, we took the sediments in the Bijiang watershed as the study object, and analyzed the Pb pollution characteristics in the sediments of the Bijiang watershed by field investigation and statistical analysis. The results showed that: (1) the average content of Pb in the sediments of the Bijiang watershed was 1764.23 mg/kg; (2) the content of Pb in sediments was upstream>midstream>downstream; (3) the single factor pollution index of Pb in the sediments of the Bijiang watershed was extremely high, and the average single factor pollution index of upstream, midstream and downstream was 6.04, 2.51 and 2.03, respectively. Based on the comprehensive analysis of Pb content and single factor pollution index in the sediments of the basin, it is found that the pollution status of Pb in the Bijiang watershed is serious, showing an upstream>midstream>downstream trend, which is likely to affect the coastal farmland soil.

  Soil Moisture Dynamics and Response to Precipitation Under Different Land Use Patterns: A Case Study of Shallow Mountain Dry Land in Huzhu, Qinghai Qiao Bin, Chen Guoqian, Shi Mingming, Zhao Huifang, Zhu Cunxiong, Cao Xiaoyun, Shi Feifei 2020, 36 (13):  115-123.  DOI: 10.11924/j.issn.1000-6850.casb19040048 Abstract + ( 394 )   HTML ( 6 )   PDF ( 1795KB )   ( 58 ) To find out the dynamic changes of soil moisture in the dry farming areas of Qinghai and to ensure the formation of crop yields and grain production safety, we studied the seasonal dynamics and vertical profile characteristics of soil moisture, and its responses to precipitation under different land use patterns in the shallow dry-land of Huzhu, Qinghai. The results showed that: (1) the soil moisture content of the tillage layer (0-30 cm) under different land use patterns had obviously dry-wet cycle changes, the land use pattern had no significant effect on the seasonal variation of soil moisture (P>0.05), but the precipitation events and precipitation levels were the dominant driving forces affecting the seasonal dynamics of soil moisture content in the tillage layer (0-30 cm); (2) 0-30 cm soil layer was the rain-fed layer, its soil moisture seasonal dynamics could be divided into dry period, wet period, normal period and transition period; the occurrence of soil drought generally began with the surface layer and gradually extended to the deep soil with the increase of the soil moisture loss; (3) the soil moisture dynamics of 4 land use types were basically consistent with the changes of the previous precipitation, and the soil water content of the subsurface (10-20 cm) and the deep (20-30 cm) were significantly correlated with the cumulative precipitation in the previous period (P<0.01). Therefore, the “shallow buried drip irrigation technology” is an effective way to seek the balance of soil water supply in the dry farming area of Qinghai with frequent drought events.

  Environmental Parameters of Double Membrane Arch Shed with Different Spans in Arid Zone of Central Ningxia in Winter Ma Ling, Huang Lingdan, Wang Rong, Ma Rong, Yang Changxin, Yang Dongyan 2020, 36 (13):  124-130.  DOI: 10.11924/j.issn.1000-6850.casb18120102 Abstract + ( 358 )   HTML ( 0 )   PDF ( 1315KB )   ( 41 ) To explore the variation law of temperature, humidity and light intensity of different span arch sheds in the arid belt of central Ningxia, we selected four local double membrane arch sheds spanning 8, 10, 16 and 20 meters, and used zigvine wiring equipment to detect relevant environmental parameters. The results showed that the greenhouse environment was greatly affected by the external weather, and the variation trend of environmental parameters in these four arch sheds was almost the same except some differences. In terms of temperature, with the increase of the span, the average temperature of 16-meter-span in January was the highest, followed by that of the 8-meter-span and 12-meter-span, and that of the 10-meter-span was the lowest. In the three typical weathers of sunny, snowy and cloudy days, the all-day temperature of the 10-meter-span could be maintained at a high level. In terms of humidity, the four spans could maintain relatively appropriate air humidity (relative humidity 40%-70%). The light intensity is low in the four arch sheds and showed a single peak curve in sunny, snowy and cloudy days. Generally speaking, the 10-meter-span shed can maintain good temperature, humidity and light transmittance in winter, and is more suitable for local promotion.

  Rhizoctonia solani to Hexaconazole: Sensitivity and Resistance Monitoring Liu Huifang, Liu Shijiang, Ding Yi, Zhao Qijun, Li Rongyu, Yang Fan 2020, 36 (13):  131-135.  DOI: 10.11924/j.issn.1000-6850.casb19010112 Abstract + ( 510 )   HTML ( 14 )   PDF ( 1419KB )   ( 192 ) In order to evaluate the resistance risk of Rhizoctonia solani to hexaconazole the sensitivity of 101 R. solani strains to hexaconazole using mycelium growth rate method, which isolated from 7 rice areas of Guizhou, Hubei, Hunan and Henan Provinces, and the baseline sensitivity of R. solani to this fungicide was also established. The results showed that the EC50 of hexaconazole to R. solani in different rice areas was 1.0751 to 2.9228 mg/L, with a mean of 1.8081 mg/L, and the sensitivity differences strains were 2.72 times. The frequnecy of sensitivity was in approximately normal distribution(W=0.980,P=0.157>0.05), and the mean EC50 values could be used as the baseline sensitivity of R. solani to hexaconazole, and therefore the mean EC50 values was used as the baseline sensitivity of R. solani to hexaconazole, and the resistance monitoring during 2016-2018 of R. solani showed that the R. solani strain was still sensitive to hexaconazole. The results of this study provide references for field medication.

  Joint-toxicity Measurement of Pydiflumetofen and Tebuconazole to Fusarium pseudogramineaqum Dou Junxia, Geng Zhongyi, Zhao Jinglan, Sun Guobo 2020, 36 (13):  136-139.  DOI: 10.11924/j.issn.1000-6850.casb19010026 Abstract + ( 453 )   HTML ( 2 )   PDF ( 1291KB )   ( 64 ) To explore the joint-toxicity of pydiflumetofen and tebuconazole to Fusarium pseudogramineaqum, carry out the selection of efficient medicament, and provide a theoretical foundation for designing drug prophylaxes, through the conventional tissue isolation, Fusarium pseudogramineaqum strains were isolated from infected samples in Tai’an and surrounding areas, and the pathogenicity was measured. The indoor bioactivities of pydiflumetofen and tebuconazole to Fusarium pseudogramineaqum were detected by mycelium growth rate method. The results showed that EC50 of pydiflumetofen and tebuconazole to Fusarium pseudogramineaqum was 0.107 mg/L and 0.906 mg/L, respectively, which indicated that the indoor bioactivity of pydiflumetofen was better than that of tebuconazole. Among the five ratios of pydiflumetofen and tebuconazole, the minimum EC50 was found at ratio 1:1 (0.157 mg/L), and the maximum EC50 was found at ratio 1:8 (0.303 mg/L). The SRs of these five ratios were 1.22, 1.54, 1.85, 1.98 and 1.63, among which the SRs of ratio 1:2, 1:4, 1:6 and 1:8 were greater than 1.5. It indicated that all these four ratios had synergistic effect on Fusarium pseudogramineaqum, and the effect of ratio 1:6 was the most obvious.

  Maize Germplasms and New Combinations Resistant to Rough Dwarf Disease: Identification and Analysis Lu Zhenyu, Huang Zhiyin, Zhang Chao 2020, 36 (13):  140-144.  DOI: 10.11924/j.issn.1000-6850.casb19010065 Abstract + ( 368 )   HTML ( 1 )   PDF ( 1131KB )   ( 74 ) To identify and screen new maize varieties with resistance to rough dwarf disease suitable for cultivation in Huanghuaihai Region, the resistance to rough dwarf disease of 295 maize inbred lines and 10 high-yield hybrid combinations were identified by field natural disease identification method. 12 maize inbred lines with high resistance, 32 maize inbred lines with resistance, 69 maize inbred lines with moderate resistance, 71 maize inbred lines with susceptibility to disease and 115 maize inbred lines with high susceptibility, and 3 maize hybrid combinations with resistance to rough dwarf disease were identified. Among them, 12 maize inbred lines with high resistance can be directly used for breeding new maize varieties resistant to rough dwarf disease. At the initial stage of breeding new maize varieties resistant to rough dwarf disease, it is necessary to ensure that the maternal and male parents of maize hybrid combinations reach above the level of moderate resistance, or that one of their parents must be inbred lines with high resistance to rough dwarf disease.

  Structures and Biodiversity of Fungal Communities in Rhizosphere Soil of Root Rot Diseased Garlic Xie Yuqing, Mao Jun, Wang Wei, Zhang Zhidong, Zhu Jing, Gu Meiying, Tang Qiyong, Song Suqin, Huang Wei, Wang Bo, Zhang Lijuan 2020, 36 (13):  145-153.  DOI: 10.11924/j.issn.1000-6850.casb19020043 Abstract + ( 398 )   HTML ( 5 )   PDF ( 1421KB )   ( 167 ) The aim is to investigate the difference in structure and biodiversity of rhizosphere fungi communities when root rot occurs, clarify the relationship between garlic root rot and the diversity change of rhizosphere soil fungus community, explore the microecological mechanism of root rot occurrence, and provide a theoretical basis for the prevention and control of the disease. High-throughput sequencing method was used to analyze the fungal ITS region sequences of the total DNA of garlic rhizosphere soil in the fields affected by garlic root rot for 3 consecutive years in Xinjiang. The results showed that Ascomycota and Zygomycota were the main phyla in rhizosphere soil of diseased garlic, and the high levels of Ascomycota were closely related to the occurrence of garlic root rot disease. Totally 137 genera were found by annotation, of which 19 genera had great correlation with garlic root rot. The abundance of Fusarium spp. in rhizosphere soil of diseased plants was significantly higher than that of healthy plants. With the increase of the onset time, the number and biodiversity of fungi decreased year by year. Garlic root rot disease is closely related to the structure and diversity of rhizosphere fungi community, and the change of the balance and diversity of soil fungi is a major cause of root rot.

  Lactulose: Control Effect on Cucumber Fusarium Wilt and Its Induced Resistance in Cucumber Wang Fang, Wei Tingting, Mao Zhiqiang, Jiao Jiao, Cui Shunyan, Zhou Fan 2020, 36 (13):  154-159.  DOI: 10.11924/j.issn.1000-6850.casb20190400052 Abstract + ( 466 )   HTML ( 0 )   PDF ( 1415KB )   ( 57 ) To explore the control effect and elementary mechanism of lactulose on cucumber Fusarium wilt, samples treated with different concentrations of lactulose and activity of related resistance enzymes were tested on cucumber. Inhibition rate of lactulose on Fusarium oxysporum f. sp. cucumerinum was determined by the growth rate method, the control effect test was carried out with radicle inoculation method and root inoculation method in potted cultivation, and the activity of related resistance enzymes were assayed by spectrophotometry. 1 mg/L lactulose had the best control effect in the concentration gradient test, and the control effect was 43.87% and 41.97% through seed soaking at radicle stage and spray at cotyledon stage, respectively, followed by the control effect of 0.1 mg/L lactulose, which was 39.62% and 37.21%, respectively. However, in vitro activity against Fusarium oxysporum f. sp. cucumerinum test showed that lactulose had no activity. The activity test of peroxidase(POD), polyphenol oxidase(PPO), catalase(CAT) and phenylalanine ammonia lyase(PAL) in cucumber showed that lactulose treated samples expressed higher level of activity than that of control, especially PAL activity of seed soaking at radicle stage and spray at cotyledon stage with 1 mg/L lactulose increased by 97.5% and 92.4%, respectively. In summary, the main mechanism of controlling cucumber Fusarium wilt is the induced resistance of cucumber by lactulose, which can be used as a new kind of biological pesticide in agricultural plant disease prevention and has great potential for development.

  Soil Microbial Community Changes: Effects on Soil-borne Diseases and Biological Regulation Gao Fen, Yan Huan, Wang Mengliang, Qin Xuemei 2020, 36 (13):  160-164.  DOI: 10.11924/j.issn.1000-6850.casb19010085 Abstract + ( 527 )   HTML ( 12 )   PDF ( 1082KB )   ( 418 ) The soil-borne disease is one of the most harmful diseases in agricultural production. In this paper, the effects of changes in microbial communities on the occurrence of soil-borne diseases, including changes in soil microbial flora, diversity, community structure and microbial interactions were reviewed; the pathogenic mechanism of soil-borne diseases was discussed; and the progress in using various microbiological agents to control soil-borne diseases and regulate microbial communities in soil was also summarized. The existing problems were analyzed and some suggestions were put forward to improve the biological control efficacy in the future.