Current issue

• 2021 Vol.37 No.17 Published:15 June 2021

  Effects of Rice-crayfish Ecological Mode and Mechanical Planting Density on Yield and Quality of High-quality Taste Japonica Varieties Dong Minghui, Gu Junrong, Li Jinbin, Wang Dongming, Song Yunsheng, Chen Peifeng 2021, 37 (17):  1-12.  DOI: 10.11924/j.issn.1000-6850.casb2020-0233 Abstract + ( 365 )   HTML ( 13 )   PDF ( 1275KB )   ( 98 ) To understand the effects of rice-crayfish ecological planting and breeding on the yield and quality of fine palatable japonica rice in Taihu Lake region, and provide reference for the decision-making of rice-crayfish ecological planting and breeding, five rice varieties (lines) with good taste and two planting densities were selected to analyze the characteristics of rice yield and quality formation under different modes of rice-crayfish ecological planting and breeding and traditional rice cultivation. The results showed that the soil physical and chemical properties were significantly improved in rice-crayfish ecosystem compared with that of traditional field cultivation. The number of effective panicles increased significantly, but panicle formation rate, grain number per spike, seed setting rate, 1000 grain weight and yield decreased significantly. The chalkiness trait was significantly improved by the ecological planting and breeding, the contents of protein and amylose significantly were increased, as well as the disintegration value and gelatinization temperature, and the subtracting value was decreased. Reducing planting density could improve rice quality. There were differences among the varieties, and some related traits of rice quality were significantly affected by the interaction between planting patterns and varieties. In general, rice varieties with fine palatable quality is suitable for the long term rice-crayfish ecological planting and breeding, and proper reduction of nitrogen and planting density could ensure safe and stable production and achieve better taste quality.

  Distribution Characteristics of Beet Root Exudates in Seedling Stage Wang Qiuhong, Song Baiquan, Wang Xiaochun, Jing Ruonan, Yang Xiya, Zhou Jianchao 2021, 37 (17):  13-18.  DOI: 10.11924/j.issn.1000-6850.casb2020-0477 Abstract + ( 467 )   HTML ( 7 )   PDF ( 3027KB )   ( 90 ) The content and distribution of root exudates directly affect the population, structure and function of rhizosphere microorganisms, which indirectly affect the availability of rhizosphere nutrients and crop growth. In this study, the root exudates of sugar beet seedlings were collected and cultured in a sand culture basin. The three major types of root exudates were measured by high performance liquid chromatography, including the common 17 amino acids, 10 organic acids and 4 saccharides in soil. The contents and distribution of amino acids, organic acids and saccharides were analyzed at different distances from the surface of the beet root. The results showed that: in general, the content of root exudates from the organic nitrogen efficient variety ‘KWS8138’ was higher than that from the organic nitrogen inefficient variety ‘Beta176’, which decreased greatly from 0 to 5 mm from the root surface, and then gradually became flat. The total amino acid content, glycine, alanine, serine, arginine and tyrosine showed similar trends. The order of saccharides content was: glucose>fructose>sucrose>galactose. The content changing trend of oxalic acid and formic acid in the organic acid was that the farther away from the root surface, the lower and slower it was. Therefore, the distribution gradient of root exudates was formed along the surface of beet roots, which provided energy and carbon sources for rhizosphere microorganisms. The study could be a theoretical reference for the effective absorption and utilization of plant rhizosphere nutrients.

  Expression Analysis of Mechlppdk Gene in Cassava and Construction of RNA Interference Vector and Genetic Transformation Wang Haiyan, Chen Xin, Zhou Xincheng, Shen Xu, Kong Hua, Wang Wenquan 2021, 37 (17):  19-25.  DOI: 10.11924/j.issn.1000-6850.casb2020-0359 Abstract + ( 332 )   HTML ( 6 )   PDF ( 2138KB )   ( 44 ) The aim of this study is to clarify the expression profiles of pyruvate phosphodikinase (ppdk) in cassava and to create an interfering strain of Mechlppdk, so as to provide materials for the functional study of Mechlppdk. The cultivated cassava Arg7 was used as the research material. The expression profiles of Mechlppdk in cassava root, stem and leaf were analyzed by qPCR method; the interference vector of Mechlppdk was constructed by RNA interference method, and then transformed into friable callus of cassava. The transgenic plantlets were obtained by cassava regeneration system, and rooting screening was carried out on the medium supplemented with antibiotics. The interference lines of Mechlppdk were identified by PCR. The expression of Mechlppdk in the interference strains were identified by qPCR. The results showed that the highest expression level of Mechlppdk was found in cassava leaves, reaching 50% of housekeeper gene. In the transit peptide region of Mechlppdk, a conservative region was selected to design primers to construct the RNA interference expression vector pART27-Mechlppdki. The expression vector was transformed into Agrobacterium tumefaciens LBA4404 and used to infect the callus of cassava friable callus, and seven positive transgenic cassava lines were obtained. qPCR showed that the transcripts of Mechlppdk decreased in different degrees. In this study, we have obtained the cassava Mechlppdk interference lines with higher interference efficiency, which could provide research materials for analyzing the function of Mechlppdk.

  Screening and Identification of a Cellulose Degrading Strain Yang Na, He Xin, Du Chunmei 2021, 37 (17):  26-31.  DOI: 10.11924/j.issn.1000-6850.casb2021-0131 Abstract + ( 306 )   HTML ( 8 )   PDF ( 1364KB )   ( 54 ) To solve the problem of low degradation rate of corn straw, stable cellulose degrading bacteria were screened from natural fermentation compost with amino acid tail liquor as the nitrogen source, aiming to lay a foundation for the preparation of efficient straw decomposition agent. Congo red staining method was adopted for preliminary screening, the determination of cellulase activity and the loss rate of corn straw weight were used for re-screening, and morphological and molecular biological methods were used to identify the efficient degrading strain. The results showed that an efficient cellulose degrading strain, SC2, was obtained. The filter paper enzyme activity, endoglucanase activity, exoglucanase activity and β-glucosidase activity of SC2 was 17.70 U/mL, 58.97 U/mL, 16.85 U/mL and 79.26 U/mL, respectively. The degradation rate of corn straw reached 33.07%. According to the colony characteristics, sporulation structure, spore morphology and ITS sequence, SC2 was identified as Aspergillus niger. Strain SC2 has good cellulose degradation ability, can effectively promote the degradation of straw and be used to prepare corn straw decomposing agent.

  Comparative Analysis of Chemical Constituents of Polygonatum Cyrtonema Hua of Red and Green Stem Type Based on LC-MS Metabolomics Jiang Wu, Weng Guohang, Chen Jiadong, Ye Chuansheng, Jiang Xinkai, Tao Zhengming 2021, 37 (17):  32-38.  DOI: 10.11924/j.issn.1000-6850.casb2020-0407 Abstract + ( 309 )   HTML ( 6 )   PDF ( 1410KB )   ( 41 ) To explore the differences of agronomic characters and medicinal effective components of Polygonatum cyrtonema from different areas of Zhejiang Province, and to provide basic data for the breeding of P. cyrtonema, the agronomic characters of red and green stem P. cyrtonema were firstly compared. Subsequently, the chemical substances of P. cyrtonema rhizome were analyzed by LC-MS and compared with NIST 11 database combined with principal component analysis. The results showed that the difference of plant height, stem diameter, leaf width and leaf area of P. cyrtonema from different provenances were extremely significant; 22 compounds were identified in 12 P. cyrtonema samples, and there were significant differences in VIP values of chemical components and metabolites between the two germplasms. The place of origin and environment of P. cyrtonema not only affect the apparent properties of plants, but also influence the formation and accumulation of its chemical substances. Thus, the agronomic properties and medicinal active components of P. cyrtonema with red stem are better than those with green stem, and the results can provide a theoretical basis for P. cyrtonema breeding and industry promotion in Zhejiang.

  Lycoris: A Review on Bulb Development Mechanism and Regulation Xu Junxu, Li Qingzhu, Yang Liuyan, Li Xin, Wang Zhen, Zhang Yongchun 2021, 37 (17):  39-44.  DOI: 10.11924/j.issn.1000-6850.casb2020-0290 Abstract + ( 273 )   HTML ( 7 )   PDF ( 1085KB )   ( 57 ) Lycoris is a genus of plants with flowering bulbs that have high ornamental and medicinal value, with a great potential of industry development. However, the slow growth and low regeneration efficiency of their bulbs under natural condition severely restrict the development of Lycoris industry. This review analyzed the physiological mechanism and regulatory measures of bulb and bulblet development respectively, and focused on the changes of carbohydrate metabolism and endogenous hormone regulation during these two biological processes. It also summarized the regulatory measures of bulb development, including exogenous hormones application, fertilization, and agronomic measures. In addition, this review pointed out the weak basic research and the imperfect supporting industrial technology system during the development of Lycoris industry, and provided suggestions on accelerating the industry, including strengthening the basic research of bulb development, forming high-efficiency breeding and ecological cultivation technology system, and building integrated industrial chain for Lycoris bulbs.

  Effects of Soil Organic Matter on Nitrogen Content in Dryland Orchard Zhang Shuqiang, Yao Zhilong 2021, 37 (17):  45-50.  DOI: 10.11924/j.issn.1000-6850.casb2020-0539 Abstract + ( 420 )   HTML ( 4 )   PDF ( 1311KB )   ( 55 ) The study aims to explore the correlation and spatial distribution of soil nutrients for the sustainable utilization of orchard soil. The chemical analysis was conducted to determine soil organic matter and nitrogen content in 30 main apple production areas in Qingyang. The results show that soil organic matter is significantly correlated with soil total nitrogen (y=0.055x+0.140, R2=0.940), while NaOH-hydrolyzed nitrogen is not obviously correlated with soil organic matter (y=3.061x+26.65, R2=0.414) and total nitrogen (y=55.28x+18.83, R2=0.441) in 0-20 cm soil. Soil organic matter is significantly correlated with soil total nitrogen (y=0.045x+0.250, R2=0.721), while NaOH-hydrolyzed nitrogen is not obviously correlated with soil organic matter (y=2.237x+23.84, R2=0.158) and total nitrogen (y=57.47x+5.141, R2=0.298) in 20-40 cm soil.

  Effects of Maize Straw Cellulose-based Super Absorbent Polymer on Soil Water Retention Capacity and Root Growth of Wheat Fan Zhen, Ding Xinhui, Zhao Dan, Sun Yu, Qi Hongyu, Jiang Yongfang, Tian Xiaofei 2021, 37 (17):  51-57.  DOI: 10.11924/j.issn.1000-6850.casb2020-0466 Abstract + ( 388 )   HTML ( 6 )   PDF ( 2609KB )   ( 55 ) To study the utilization potentiality of maize straw cellulose-based super absorbent polymer (SAP) in agricultural production, the structures of SAP before and after water absorption were characterized. Meanwhile, the effects of SAP application on soil water retention capacity and root growth of wheat under water stress was studied. The results showed that the swelling of SAP decreased soil bulk density, increased soil maximum water content by 19.1% to 67.6% compared to the treatment without SAP, while decreased the evaporation rate in the first 3 days. Under mild (60%-70% of soil water retention capacity) and moderate (40%-50% of soil water retention capacity) water stress, the root length with 0.4% w/w SAP application increased by 15.9% and 24.7%, while the root activity increased by 29.6% and 43.5%, respectively, compared with those without SAP. However, no significant difference of root activity and root biomass were observed under well-watered condition (75%-90% of soil water retention capacity). In summary, the SAP with excellent water retention capacity is effective in promoting the root growth of wheat, and could relieve the inhibiting effect of water stress on winter wheat root growth.

  The Technology of Reducing Chemical Fertilizer and Increasing Economic Benefit of Protected Peach in Sandy Soil Qiu Meihua, Guo Dejie, Ma Yan, Wang Guangfei, Liang Yonghong 2021, 37 (17):  58-64.  DOI: 10.11924/j.issn.1000-6850.casb2021-0140 Abstract + ( 313 )   HTML ( 4 )   PDF ( 1323KB )   ( 44 ) Excessive use of chemical fertilizers is common in protected cultivation of peach in sandy soil. It is necessary to explore the technology of reducing chemical fertilizer and increasing economic benefit. A field experiment was carried out in a greenhouse to study the effects of commercial organic fertilizer (OF), bio-organic fertilizer (BOF), balanced fertilization (BF) and integrated mode of fertilization technology (MF) under the condition of reducing chemical fertilizer nutrients by 30% on peach yield, fruit quality and soil properties. Compared with conventional fertilization (CK), OF, BOF, BF and MF treatments increased peach yield by 4.5%, 3.4%, 1.5% and 9.1%, respectively. MF treatment significantly increased yield. OF and MF treatments improved fruit soluble sugar and nitrate, while BF treatment significantly improved fruit nitrate. BF and BOF treatments significantly reduced the excess available P, available K and salt content in soil. OF and MF treatments decreased available P and K content but slightly increased nitrate N content and significantly increased organic matter content. MF treatment had the best improving effect on soil microbial abundance, activity, and diversity, followed by BOF and OF treatments, and finally was BF treatment. Correlation analysis showed that the improvement of fruit yield and quality was mainly attributed to the decrease of soil available P, available K, and salt content and the significant improvement of soil biological fertility. According to fertilizer costs and economic benefits, MF treatment increased income by 8300 yuan/hm2, followed by BOF treatment (5400 yuan/hm2) and BF treatment (5300 yuan/hm2), and finally OF treatment (2000 yuan/hm2). Therefore, the integrated mode of organic fertilizer, bio-organic fertilizer, and balanced fertilization is suitable for protected cultivation of peach in sandy soil.

  Temporal Variation of Rootzone Soil Fertility in Different Planting Years of Peach Orchards Guo Xinsong, Yu Xiaodong, Zhang Jing, Zhang Peiping, Zhao Hua, Du Dongliang, Ma Xinlei, Ding Fangjun 2021, 37 (17):  65-71.  DOI: 10.11924/j.issn.1000-6850.casb2021-0051 Abstract + ( 281 )   HTML ( 5 )   PDF ( 1608KB )   ( 45 ) Rhizosphere soil fertility is the foundation of fruit tree growth. In this study, the changes of soil physical, chemical and biological properties in the root zone of peach trees planted by 5, 10, 15 and 20 years were analyzed, to reveal the change rules of rhizosphere soil fertility in peach orchards with different planting years, and explore the main soil fertility factors affecting peach yield and quality. The study could provide a theoretical basis for peach tree cultivation and management. The results show that with the increase of planting years, soil clay and silt increase, but the soil texture does not change; at the same time, the soil organic matter, total nitrogen, available phosphorus and available potassium present an increasing trends; soil urease and catalase could reach the maximum value in 15 years’ planting; soil fungi and bacteria show a decreasing trend with the increase of planting years; however the microbial biomass nitrogen decreases year by year. Thus, there is a certain correlation between soil fertility factors, and the interactions between different soil fertility factors affect the changes of soil fertility in peach orchards. Soil organic matter, microbial biomass carbon and soil enzyme activity are the main factors affecting soil fertility. Peach yield in 15 years planting is the highest and declines after 15 years planting. Among the soil fertility factors, soil available potassium, organic matter, microbial biomass carbon and soil urease are the main factors affecting the peach yield and quality (soluble solids).

  Influence of Municipal Solid Waste Stacking on Soil Bacterial Community Structure and Function Cheng Zhichao, Wu Wenyan, Song Yonghui, Sui Xin, Li Mengsha, Yang Libin 2021, 37 (17):  72-79.  DOI: 10.11924/j.issn.1000-6850.casb2021-0120 Abstract + ( 212 )   HTML ( 7 )   PDF ( 2194KB )   ( 59 ) To explore the effect of municipal solid waste stacking on the structure, diversity and function of soil bacteria, by using the Illumina high-throughput sequencing technology, we investigated the soil bacterial community structure and function from the municipal solid waste stacking soil and the no waste stacking soil 50 m away from waste stacking soil in Shuangcheng District, Harbin. The results showed that the control group and the treatment group obtained 85435 and 76432 effective sequences, respectively; compared with the control soil, the Chao1 index of bacteria in treatment soil decreased by 14.47% and the Shannon index decreased by 15.01%; the dominant bacterial phyla of two treatment soils were Proteobacteria, Bacteroidetes, Chloroflexi, Acidobacteria, Actinobacteria, Gemmatimonadetes and Cyanobacteria, but the relative abundances were significantly different, in which Chloroflexi increased most by 7.0% and Bacteroidetes decreased most by 12.6%. The relative abundances of Bacillus and Xanthomonas were the highest. Compared with the control treatment, the relative abundance of Bacillus increased by 4.3%. The results of PICRUSt prediction showed that there were 41 KEGG secondary functional groups in the 6 metabolic pathways, of which amino acid metabolism and carbohydrate metabolism were the dominant functions of the two soil samples in the secondary functional groups. The solid waste stacking had a significant impact on the abundance of functional genes. Solid waste stacking has significant negative effect on the abundance and diversity of soil bacteria, as well as a significant effect on the relative abundance of soil bacterial communities and their function, and the study result could provide theoretical data for elucidating the soil quality after solid waste stacking.

  Choice Experiment Method and Ecological Value Evaluation: Principle and Domestic Application Qin Yanqiang, Yu Yaliang, Liu Ruihan 2021, 37 (17):  80-86.  DOI: 10.11924/j.issn.1000-6850.casb2020-0531 Abstract + ( 269 )   HTML ( 7 )   PDF ( 1247KB )   ( 48 ) To sort out the application research of ecological value assessment by using the choice experiment method in China, 59 related documents are analyzed. The results show that the domestic research on ecological value assessment can be roughly divided into the research on the ecological value of scenic spots and the study of regional value. The tourism cost in the study of ecological value of scenic spots is 265.51-1381.38 per visit, and the estimated value by ticket is 7.78-127.12 yuan per visit; the regional ecological value is mainly paid by personal willingness and family willingness, among which, the environmental value of individual willingness payment is 23.77-1066.99 yuan per year, while the household willingness payment is 21.77-769.42 yuan per year. The results show that the ecological value calculated by travel cost is higher in scenic spots valuation study, and the value measured by individual willingness payment is more different in the estimation of regional ecological value. Therefore, attention should be paid to the difference between different accounting methods.

  The Application of Model Organisms Drosophila melanogaster to the Toxicology of Water Environment Pollutants: Research Progress Wu Jinlan, Lu Chenying, Wu Mingjiang, Tong Haibin 2021, 37 (17):  87-93.  DOI: 10.11924/j.issn.1000-6850.casb2020-0500 Abstract + ( 392 )   HTML ( 6 )   PDF ( 1126KB )   ( 85 ) The economic development and human activities have accelerated the destruction of the ecological environment, and the discharge of industrial and domestic sewage has aggravated the pollution of rivers and seawater, as well as the harmful substances to human health continuously. Drosophila melanogaster is a widely used model organism. Compared with other animal models, D. melanogaster has many advantages such as low feeding cost, short life cycle, high fecundity, relatively simple genetics, multiple mutant phenotypes and easy to be identified, which is a model organism widely used and suitable for studying human diseases and toxicology. In this review, the toxicological studies of volatile organic compounds, fluoroquinolones, heavy metals, pesticides and microbial toxins in the water environment on D. melanogaster were summarized, and the advantages of D. melanogaste as a classic model organism in studying toxicological mechanisms and screening anti-toxic drugs and the prospects for the future development trend of D. melanogaster were discussed.

  ‘The Regulation by Estradiol on Mammalian Endometrial Angiogenesis: Research Progress Sun Wanxu, Huang Qizhen, Li Boyu, Su Yunze, Zhang Qiaochu, Xiao Longfei, Qi Xiaolong, Xing Kai, Wang Xiangguo, Sheng Xihui, Guo Yong, Ni Hemin 2021, 37 (17):  94-98.  DOI: 10.11924/j.issn.1000-6850.casb2020-0251 Abstract + ( 301 )   HTML ( 5 )   PDF ( 1085KB )   ( 51 ) With the development of animal husbandry, the pregnancy problem of female animals has become more and more prominent. It is worth noting that in the clinical practice of animal husbandry and veterinary medicine, insufficient formation of blood vessels in the uterus of animals during pregnancy could increase the difficulty in embryo implantation, miscarriage and fetal development. In recent years, there have been many studies on the role and mechanism of tumor angiogenesis in clinics and laboratories. Since there is a similarity between the growth mechanism of tumor blood vessels and the growth mechanism of blood vessels in the uterus, based on the relevant research of tumor angiogenesis, we studied the role of angiogenesis and the mechanism of angiogenesis. The research could lay a foundation for further exploring the mechanism of estradiol on the formation of endometrial blood vessels in ruminants.

  Effect of Different Bacterial Strains on In-situ Collection and Fermentation of Chicken Manure Jin Chongfu, Chen Yingjiang, Yang Zhiqing, Lu Jian, Hou Fuyin, Shi Kai, Chen Changkuan 2021, 37 (17):  99-104.  DOI: 10.11924/j.issn.1000-6850.casb2020-0303 Abstract + ( 205 )   HTML ( 5 )   PDF ( 1358KB )   ( 42 ) To solve the problem that fecal contamination affects chicken health and contaminates the environment in small and medium-sized chicken enterprises, the study compared the effects of different combinations of bacterial strains and padding material composition on in-situ collection and fermentation of chicken feces, and studied the changes of various indexes during in-situ collection and fermentation of chicken feces. The results showed that the temperature range of in-situ fermentation was 32~60℃. In the in-situ collection of different padding materials, the bacterial cola group showed better fermentation effect than other bacterial combinations. The best effect of nitrogen fixation is A (Ferruginous bacteria) test group. The concentration of total phosphorus in group C (Funong) and Group E (Bacterial cola) reached 31.69% and 16.09%, respectively. C (Funong) and E (Bacterial cola) had the best total potassium enrichment to 9.88% and 12.84%, respectively. In conclusion, the overall fermentation effect of the bacteria cola group is better than that of other experimental groups.

  Effect of Pipe Drainage on Scale Farmland Rice Nutrient Absorption and Yield Composition Jiang Lingjie, Dong Linlin, Fan Peng, Cao Yifan, Zhou Zhengping, Shen Xinping, Lu Changying, Shen Mingxing 2021, 37 (17):  105-111.  DOI: 10.11924/j.issn.1000-6850.casb2020-0496 Abstract + ( 290 )   HTML ( 6 )   PDF ( 1474KB )   ( 54 ) To explore the effect of underground pipe drainage on the absorption of nitrogen, phosphorus and potassium and yield components of rice plants at later stages of growth, ‘Nanjing 46’ was used as the test material, an experiment was conducted in two adjacent field blocks of underground pipe drainage and traditional open ditch drainage in Taicang Donglin Farm of Suzhou City. Rice samples were collected at different locations from the ditch (seedling ditch spacing) and different locations from the pipe (seedling pipe spacing) in the underground pipe drainage field block and the sampling of the traditional open ditch drainage field block was used as a control, to analyze the difference of the nitrogen, phosphorus and potassium content and the yield composition of the rice plants at the jointing booting stage, long earing stage and mature stage. The results showed that: with the increase of the seedling ditch spacing, the absorption of nitrogen, phosphorus and potassium of rice plants had a tendency to decrease, and the area closer to the drainage ditch had the most significant effect. The nitrogen, phosphorus and potassium content and yield of each organ of the rice plant at the seedling pipe spacing of 2.5 m were the highest. Compared with the control group, the absorption of nitrogen, phosphorus and potassium in different organs of rice could have a maximum increase by 25.17%, 80.16%, and 35.19%, respectively. The yield reached 9.97 t/hm2 when the seedling ditch spacing was 15 m and the seedling pipe spacing was 2.5 m, which was 15.22% greater than the control group. The difference in yield was mainly caused by the number of grains per spike, seed setting rate and thousand-grain weight of the rice population. Underground pipe drainage could effectively increase the absorption of nitrogen, phosphorus and potassium in paddy field and increase part yield, but free underground pipe drainage might cause the loss of surface soil nutrients directly above the underground pipes and affect the absorption of nitrogen, phosphorus and potassium in rice plants, and the law of nitrogen, phosphorus and potassium absorption should be further analyzed in the later stage in combination with the relationship between soil leakage intensity or leakage amount and soil nutrient content.

  Study on the Flow Characteristics of Micro-sprinkler Hose with Different Structural Parameters Zhang Mingzhi, Lu Zhenguang, Yin Qingfang, Li Yuan, Qiu Xinqiang, Yang Haochen, Zhang Yushun, Yin Yuqing 2021, 37 (17):  112-119.  DOI: 10.11924/j.issn.1000-6850.casb2020-0075 Abstract + ( 470 )   HTML ( 4 )   PDF ( 3088KB )   ( 40 ) Micro-sprinkler hose, as a high-efficiency and water-saving irrigation technology, has been widely used in winter wheat and summer maize production, this paper aims to find out the main structural parameters that affect the single group flow of micro-sprinkler hose. A completely randomized experiment was conducted to study the effects of different number of micropores (X1, 1, 2, 3, 5), angle for micropores (X2, 0, 30, 60, 90o) and spacing between of micropores (X3, 0.2, 0.4, 0.8, 1.2cm) on the flow (Q) of the micro-sprinkler hose. The results showed that the number of micropores played a leading role in influencing the single group flow, followed by the angle of micropores, and the spacing between of micropores had the smallest influence. When the number of micropores was increased from 1 to 5 micropores, the peak value of wetting area, wetting rate, flow and irrigation intensity were increased by 89.11%, 13.73%, 339.38% and 25.06%, respectively. With the spacing increase between the micropores and angle for micropores, the wetting area and single group flow increased at first and then decreased, the wetting rate showed a decreasing trend, and the peak irrigation intensity did not change significantly. The multiple linear regression equation was Q=22071.74 X1+11247.09 X2-7.34 X3-34430.54. The model can explain more than 80.00% of the single group flow, and can be used to predict the single group flow. This study can provide theoretical reference for the parameter design of micro-sprinkler hose.

  Research Progress on Flavonoids of Cannabis sativa L Jiang Shuo, Wan Lu, Xu Zhexiang, Yan Jiajia, Zheng Chunying 2021, 37 (17):  120-128.  DOI: 10.11924/j.issn.1000-6850.casb2020-0480 Abstract + ( 292 )   HTML ( 6 )   PDF ( 1628KB )   ( 50 ) To efficiently utilize the flavonoids of Cannabis sativa L and systematically carry out research on flavonoids of Cannabis sativa L, in this study, the structures, synthesis pathways, biological activities and analysis methods of flavonoids of Cannabis sativa L were reviewed. The results showed that 26 flavonoids compounds of Cannabis sativa L were contained in the Cannabis sativa L, and the main structure types of these flavonoids compounds were flavonoids and flavonols. Moreover, based on the classical synthetic pathway of flavonoids, the biosynthesis pathway of cannflavins A and cannflavins B, which were the characteristic flavonoids of Cannabis sativa L., were identified. Meanwhile, the biological activities of Cannabis sativa L, such as anti-tumor, neuroprotective, antidepressant and so on, were also summarized. According to the structural characteristics and biological activities, LC-MS was established as the efficient and rapid method to analyze the flavonoids in Cannabis sativa L. The study could provide certain reference for the research and application of the flavonoids in Cannabis sativa L.

  Evaluation of the Uncertainty in Determining Organophosphorus and Pyrethroid Pesticides Residue in Vegetables and Fruits by Gas Chromatography Yu Tingting, Qiu Pengcheng, Chen Qiang, Shi Fu, Yang Yajun 2021, 37 (17):  129-136.  DOI: 10.11924/j.issn.1000-6850.casb2020-0216 Abstract + ( 342 )   HTML ( 5 )   PDF ( 1372KB )   ( 49 ) The uncertainty of measuring organophosphorus and pyrethroid pesticides residue in vegetables and fruits by gas chromatography was evaluated in this study. Taking NY/T 761—2008 standard method as the research object, chlorpyrifos and fenpropathrin were selected to represent the first and second parts of the method respectively and the uncertainty of the method was evaluated from seven aspects including the sample pretreatment process, instrument measurement and standard solution preparation etc. The relative expanded uncertainty of chlorpyrifos and fenpropathrin pesticide residue is 0.9% and 1.0% (k=2) respectively, among which the uncertainty component introduced by gas chromatograph peak area, standard solution preparation and standard recovery rate are the main source. In order to reduce the uncertainty of test results, it is necessary to improve the stability of equipment, simplify the preparation process of standard solution and improve the operation ability in practice. Simultaneously, the results of uncertainty should be applied to judge whether the detection data is to be in the critical value of limit.

  Current Status and Development Strategy of the Channel Catfish Industry in Jiangsu Zhong Liqiang, Wang Minghua, Chen Xiaohui, Zhang Shiyong, Jiang Hucheng, Bian Wenji 2021, 37 (17):  137-143.  DOI: 10.11924/j.issn.1000-6850.casb2020-0426 Abstract + ( 407 )   HTML ( 5 )   PDF ( 1268KB )   ( 62 ) Since 2017, the cultivation area and total production of channel catfish increased dramatically in Jiangsu Province, reaching a cultivation area of 10,000 hm2 and accounting for 25% of total production in China. This review outlines the consumer trends, bottleneck of fry supply, culture mode and processing industry of channel catfish in Jiangsu Province. At the same time, the problems of channel catfish industry in Jiangsu Province are also summarized. With the enlargement of the cultivation scale along the coast, there is a savage imbalance between supply and demand in fingerlings and foodsize channel catfish markets. Moreover, the relatively simple product structure and market constraints are the main limits of channel catfish industry in Jiangsu Province. Based on the analysis, suggestions on the sustainable development of channel catfish industry are put forward, including reinforcing the utilization of genetically improved strains and green aquaculture model, strengthening the scientific and technological support, building brands, and exploring new markets and novel platforms.

  Effect of Adding Cellulase-Producing Compound Flora on Biogas Production by Anaerobic Dry Fermentation Zhang Chen, Yan Hongxin, Ji Dong, Wei Zhihao, Yao Zhisong, CAMARA ZOUMANA, Su Youyong 2021, 37 (17):  144-150.  DOI: 10.11924/j.issn.1000-6850.casb2021-0009 Abstract + ( 338 )   HTML ( 3 )   PDF ( 1631KB )   ( 51 ) In order to improve the utilization rate of crop straws and livestock manure, a cellulose-degrading compound flora is added to the biogas anaerobic fermentation system to improve gas production performance. The experiment used corn stalk and cow dung as raw materials. The fermentation condition was: 37℃ of fermentation temperature, 20% of total solid concentration, 30% of inoculum content, 1:2 of manure-to-grass ratio, and 1% of the compound flora was added to anaerobic dry fermentation to produce biogas. The results show that the compound flora consisting of Bacillus siamensis and Bacillus subtilis subsp. Stercoris could increase biogas production by 25% and methane production by 55%, and gas production rate of raw materials is 86.4 mL/gTS and 111.4 mL/gVS, respectively. The experiment could provide certain reference value for the utilization of biomass energy containing cellulose.

  Water-saving Irrigation Technology Adopted by Facility Vegetable Growers: Study on Influencing Factors Xie Zhengxuan, Mu Yueying 2021, 37 (17):  151-156.  DOI: 10.11924/j.issn.1000-6850.casb2020-0459 Abstract + ( 308 )   HTML ( 7 )   PDF ( 1236KB )   ( 52 ) This paper uses the dichotomous conditional value method and the COX risk proportional model to measure the willingness to pay for water-saving irrigation technology by facility vegetable growers in five provinces in the Bohai Sea rim region and analyzes the influencing factors. The results of the study show that the current adoption rate of water-saving irrigation technology by sample farmers is relatively low, and the average willingness to pay is only 4578.3yuan/hm2. The willingness to pay is significantly and positively correlated with education, family income, and the number of people engaged in facility production. Age is significantly and negatively correlated with the willingness to pay. The above results indicate that the lack of payment capacity is an important aspect that hinders the adoption of water-saving irrigation technology. Therefore, the promotion of the water-saving irrigation technology in facility agriculture requires the government and farmers to jointly bear the cost of technology adoption.

  Investigation and Analysis of Residual Mulching Film Pollution Control Behaviors of Farmers in Typical Film Covered Areas in Xinjiang Lei Lei, Tang Qiuxiang, Chen Lijun, Jin Tuo, Liu Qin, Bao Zhe 2021, 37 (17):  157-164.  DOI: 10.11924/j.issn.1000-6850.casb2020-0492 Abstract + ( 287 )   HTML ( 5 )   PDF ( 1219KB )   ( 54 ) Farmers play a key role in the treatment of residual film pollution in farmland. To promote the development of residual film treatment in Xinjiang, a questionnaire survey was conducted with farmers using mulching film in typical regions of Xinjiang, and a Logistic model was used to explore the factors affecting residual film treatment by farmers. The results indicate that the current treatment measures for residual film pollution are mainly recycling the residual film, and only 6.7% of farmers choose to use degradable mulching film; the farmers’ agricultural income, awareness level of residual film hazards, residual film recycling station, treatment effect and mechanization level are the important reasons affecting the residual film recycling behavior of farmers. When analyzing the influencing factors of farmers’ use of degradable mulching film, it is found that the number of people in one household engaged in agricultural production, the main economic sources, agricultural income and the price of degradable mulch are important factors influencing farmers’ use of degradable mulching film. Based on this, it is proposed to strengthen the publicity on the hazards of residual film and related treatment measures, enhance the research and development of residual film recycling machines and degraded mulching film, and strictly implement relevant laws and regulations to promote the treatment of residual film in Xinjiang.