Current issue

• 2021 Vol.37 No.24 Published:25 August 2021

  Main Quality Characters of Wheat: A Review Ma Sishuang, Bai Haibo, Hui Jian, Wang Jingdong, Li Shuhua 2021, 37 (24):  1-5.  DOI: 10.11924/j.issn.1000-6850.casb2020-0563 Abstract + ( 683 )   HTML ( 27 )   PDF ( 1173KB )   ( 1421 ) Wheat is the main food crop ensuring food production safety and boosting high quality development of agriculture in China, and the improvement of wheat quality becomes more and more urgent. The quality traits of wheat are complex. After years of genetic improvement, important progress has been made in the study of wheat quality traits, but the wheat quality improvement in China is still at a low level. In this paper, the research status of several important quality traits of wheat was briefly summarized, with the focus on the genetic improvement of traits that control the nutritional quality and processing quality of wheat. The paper mainly analyzed the genetic characteristics of wheat protein content, gluten content, starch content and sedimentation value, and reviewed the molecular genetic laws of each quality trait and the main genes related to regulation. With the development of molecular biology and biotech nology, the genetic regulation of wheat quality traits is clear, and molecular design breeding can be used as a key research method in the future.

  The Principal Component Analysis and SOM Cluster Analysis Identifying Salt Tolerance of Wheat Varieties at Germination Stage Han Liping, Guo Weiwei, Han Xiaofan, Li Ximei, Wang Huifang, Zhang Yumei, Qiu Hongwei 2021, 37 (24):  6-17.  DOI: 10.11924/j.issn.1000-6850.casb2020-0602 Abstract + ( 529 )   HTML ( 11 )   PDF ( 1271KB )   ( 247 ) The aims are to study the salt tolerance of different wheat varieties during the germination period, and provide a rapid and accurate identification method and a theoretical basis for the identification of salt tolerance in the germination period of wheat. In this study, we used 40 winter wheat varieties as test materials and studied the effects of salt stress on morphological indices of these wheat varieties through principal component analysis (PCA) and neural network self-organizing mapping (SOM) clustering analysis. The results of principal component analysis show that germination potential, germination rate, the maximum root length, the first leaf length and coleoptile length are the largest loads under PCA. According to the results of SOM cluster analysis, four wheat varieties, including ‘Dekang 961’, belong to high salt tolerance; fourteen wheat varieties, including ‘Jimai 22’, belong to salt tolerance; sixteen wheat varieties, such as ‘Jimai 20’, belong to medium salt tolerance, and six wheat varieties, such as ‘Lumai 21’, belong to salt sensitivity. Germination potential, germination rate, the maximum root length, first leaf length and coleoptile length could be used as the main evaluation indexes for screening salt tolerance of wheat at germination stage, and it is more scientific and convenient to identify salt tolerance of wheat at germination stage by combining principal component analysis and SOM clustering analysis method.

  Analysis of Yield Traits of Sweet Corn at Multi-location Tests in Guangdong Based on GGE-biplot Li Yuliang, Xiong Ting, Liu Jianhua, Li Gaoke, Li Wu, Xie Lihua 2021, 37 (24):  18-24.  DOI: 10.11924/j.issn.1000-6850.casb2020-0664 Abstract + ( 424 )   HTML ( 6 )   PDF ( 1899KB )   ( 308 ) To clarify the high yield and the stability of sweet corn varieties, and the representativeness and the discriminability of the testing sites in Guangdong Province regional test, the yield data of 18 sweet corn varieties of 2018-2019 Guangdong Province regional test were analyzed by GGE-biplot (genotype main effect plus genotype-environment interaction). The results showed that ‘Yuetian 33’, ‘Zhetian 808 ’and ‘Xinmeitian 816’ in the test of 2018 were in the first three places in terms of high yield and stable yield. In the test of 2019, ‘Yuetian 33’, ‘Huameitian 468 ’and ‘Xinmeitian 816’ were in the first three places in terms of high yield, and ‘Yuetian 33’, ‘Yuetian 16’ and ‘Zhengtian 89’ had the best stability. ‘Yuetian 33’ had the best comprehensive performance, stability and adaptability in the two years’ test. There is a positive correlation among all test environments, indicating that they have good representativeness. A close positive correlation is found between some of the test environments, Guangzhou and Yingde ecological zones are the most ideal sites for 2018 and 2019, respectively, which have good environmental representativeness and discriminability for sweet corn varieties.

  80 Declassified American Maize Inbred Lines: Utilization Potential Analysis Wang Changliang, Zhao Lianfeng, Chang Jianzhi, Wei Shengli, Yan Lihui, Li Yanchang, Wang Hailiang 2021, 37 (24):  25-30.  DOI: 10.11924/j.issn.1000-6850.casb2020-0666 Abstract + ( 565 )   HTML ( 14 )   PDF ( 1177KB )   ( 120 ) In order to screen out maize inbred lines with excellent combining ability from 80 declassified inbred lines of the United States, analyze their utilization potential and provide the basis for rational utilization, we used PH6WC and PH4CV as test varieties to explore the combining ability and comparative advantages of the 80 maize inbred lines by NCII genetic design. The results showed that the genetic basis of the 80 American inbred lines was rich and there were real differences. The materials could be divided into 33 female parent groups and 47 male parent groups. Among the 80 test materials, LH206, PHN66, NL001, 2FACC, 6M502A, 29MIBZ2, 1538, LH128, LH181, Lp215D, PHR30, LH214 and LH213 had excellent GCA effect value for yield. The TCA effect values of PH6WC×6M502A, PHW51×PH4CV, NL001×PH4CV and LH128×PH4CV in the cross combination were excellent, and their comparative advantages were relatively strong, so further test could be carried out. The NL001, 2FACC, 29MIBZ2 and 1538 were suitable for mechanized harvesting, and the GCA showed excellent performance. Also, 6M502A, NL001 and LH128 had relatively high general combining ability, and they could be used as key inbred lines.

  Dynamics of Carbon and Nitrogen in Root Exudation and Their Relations with Root Traits in Maize Wan Yibing, Tang Lanlan, Zhan Ming, Shang Chunhui, Yuan Jiayi, Qin Mingguang 2021, 37 (24):  31-38.  DOI: 10.11924/j.issn.1000-6850.casb2020-0517 Abstract + ( 477 )   HTML ( 5 )   PDF ( 1508KB )   ( 1051 ) The aims are to study the law about root exuding carbon and nitrogen in maize and their relationships with root traits. The maize variety ‘Dika 653’ was used as material, the method of soil-hydroponic-hybrid was used to determine the morphological indicators of root, carbon and nitrogen contents in root exudation. The results showed that the specific root carbon and nitrogen exudation (EIroot-C, EIroot-N) were higher at the early growth stage than those at the late growth stage. EIroot-C and EIroot-N had a significantly positive linear correlation with specific root length, specific root surface area and specific root volume, but had a significantly negative linear correlation with C/N ratio in root. The carbon exudation per plant (EIplant-C) and nitrogen exudation per plant (EIplant-N) increased first and then decreased during the growth period. The accmulated root carbon and nitrogen exdation reached 15.71 g/plant and 0.75 g/plant during the maize plant growth period, respectively. There was a significant quadratic relationship between EIplant-C and root length, root surface area, root volume, root dry weight, root shoot ratio and leaf area, while EIplant-N only had a significant quadratic curve relationship with root shoot ratio. The carbon and nitrogien in root exudations in maize field could be estimated accroding to the relationship between root traits and root exuding carbon and nitrogien.

  The Physiological Characteristics of Beets Under Stress: Research Progress Li Zhi, Xue Jiao, Geng Gui, Wang Yuguang, Yu Lihua 2021, 37 (24):  39-47.  DOI: 10.11924/j.issn.1000-6850.casb2021-0113 Abstract + ( 424 )   HTML ( 10 )   PDF ( 1256KB )   ( 540 ) At present, the main factors affecting the growth and development of sugar beet are water, temperature, soil salinization, etc. Therefore, it is a hot topic to study the changes of growth and physiological characteristics of sugar beet under stress. In order to study the effects of water, temperature and soil salinization on the growth and development of sugar beet, the effects of adversity stress on plant growth were summarized, and the morphological and physiological changes of aboveground parts and roots of sugar beet under stress were reviewed. Leaf is one of the most important vegetative organs of plants, and its main physiological functions are respiration, photosynthesis, transpiration and nutrient transformation. Root system is the key part of plant growth and development, which plays a role of fixing, supporting plants and absorbing and transporting nutrients. It is concluded that the response of sugar beet to adversity stress is accomplished by changing the external morphology and physiological and biochemical indexes. It is suggested that the interaction mechanism between sugar beet and the environment should be further studied in the future, and the management and development of sugar beet industry system should be strengthened so as to improve the yield and quality of sugar beet.

  Genetic Diversity of Flax Testing Varieties Based on DUS Testing Traits Zuo Zhenxing, Ji Junjian, Fu Guoqing, Wang Yao, Huo Ahong, Kou Shujun 2021, 37 (24):  48-53.  DOI: 10.11924/j.issn.1000-6850.casb2021-0385 Abstract + ( 396 )   HTML ( 7 )   PDF ( 1175KB )   ( 243 ) The aims are to optimize the DUS test technology of flax, and provide a scientific basis for the DUS test of new flax varieties. 30 flax varieties were used as test materials, 19 DUS traits were used to investigate the genetic diversity of the test varieties. The results showed that 62 allelic variations were detected in all test varieties by testing 19 morphological traits, and the mean number of allelic variation for each trait was 3.2632. The mean effective allelic variation number was 2.3716 (1.2195-5.2941). The mean Shannon-Weaver diversity index of 19 morphological testing characteristics was 0.8720 with the amplitude from 0.2449 to 1.7160. The UPGMA cluster analysis showed that the 30 flax varieties were divided into three groups. Most varieties of groupⅠandⅡ were oilseed flax, while most of group Ⅲ were fiber flax. Our results show that there are significantly positive correlations between plant height and technology length, and between capsule number of single plant and branch number of single plant. Meanwhile, there is a significantly negative correlation between plant height and capsule number of single plants. Therefore, technology length and branch number of single plant are recommended to be excluded from DUS testing traits of flax, characteristics of plant height and branch number of single plant might be effective to distinguish varieties.

  SPAD Value Estimation of Tobacco Leaves Based on Hyperspectral Fractional Differential Lv Xiaoyan, Xue Lin, Jing Xia, Zhang Chao, Xu Haiqing, Zhu Qifa 2021, 37 (24):  54-59.  DOI: 10.11924/j.issn.1000-6850.casb2020-0599 Abstract + ( 431 )   HTML ( 7 )   PDF ( 1276KB )   ( 218 ) Tobacco SPAD value was estimated based on hyperspectral fractional differential, and the aim was to improve the accuracy of hyperspectral data estimating tobacco SPAD value. Firstly, the optimal transformation method was determined to estimate the SPAD value of tobacco leaves, and fractional differential processing was carried out. Then, the characteristic wavelengths were selected based on correlation analysis, out-of-bag(OOB) data importance, and random forest (RF). Finally, the SPAD value estimation model of tobacco leaves was constructed. The results showed that: (1) The characteristic wavelengths used to estimate the SPAD value of tobacco leaves mainly included the green band (499 nm, 500 nm), the red edge band (634 nm, 636 nm, 702 nm, 703 nm, 732 nm), the near-infrared band (972 nm, 1286 nm, 1289 nm, 1295 nm, 1298 nm, 1316 nm), short infrared bands (1450 nm, 1453 nm, 1456 nm, 1806 nm). (2) The RF-SPAD model constructed with the characteristic wavelength of order 1.9 had the highest accuracy, R 2= 0.690, which was 22.1%, 42.6%, 87% higher than the 0, 1 and 2 orders respectively; RMSE= 2.799, which was reduced by 13.5%, 20.2% and 27.8% compared with 0, 1, and 2 orders, respectively. Compared with the integer order model, the RF-SPAD model constructed by using the characteristic wavelength of order 1.9 effectively improved the estimation accuracy of tobacco SPAD value, and provided a new idea for the hyperspectral fractional order differential technology to estimate SPAD value.

  Microbial Fertilizers Application in Coastal Saline Wheat Field: The Salt-reducing Effect and the Growth Response of Winter Wheat Wang Qiyao, Zhao Gengxing, Li Tao, Li Jianwei, Pan Deng, Tu Qiang 2021, 37 (24):  60-66.  DOI: 10.11924/j.issn.1000-6850.casb2020-0609 Abstract + ( 376 )   HTML ( 4 )   PDF ( 1355KB )   ( 135 ) This paper aims to explore the effects of microbial fertilizer application in coastal saline wheat field on reducing soil salt content and the growth response of winter wheat. Field experiments with different kinds of biological products and different amounts of microbial fertilizers were conducted in the coastal saline wheat field of the Yellow River Delta area. The data of soil salinity, wheat plant height, SPAD value, canopy NDVI and wheat yield were collected. The effects of microbial fertilizer on salt reduction and growth response of winter wheat were systematically analyzed by comparative analysis and variance analysis methods. The results showed that different kinds of biological product treatments had a certain salt reduction effect, and the salt contents of both the surface and the lower soil layers decreased with the range between 11.66% and 33.89%. The salt reduction effect of the microbial fertilizer was the most obvious. In each treatment, the increase of SPAD value of wheat was from 22.78% to 31.64%, the increase of NDVI value was 27.18%-44.74%, and the increase of wheat yield was 1.85%-20.49%. The effect of microbial fertilizer treatment was the best. When the application rate of microbial fertilizer was less than 7 kg/hm 2, the salt-reducing effect increased with the increase of the application rate, and the growth and yield of winter wheat also increased significantly. While when the application rate exceeded 7 kg/hm2, the effect decreased, so the best application rate was 7 kg/hm2. Our results indicate that the application of microbial fertilizer in coastal saline wheat field has significant salt reduction effect and a positive impact on the growth and yield of winter wheat.

  The Effect of NyPa Forage on Soil Improvement of Coastal Saline-alkali Land Qiao Yanhui, Wang Yuehai 2021, 37 (24):  67-72.  DOI: 10.11924/j.issn.1000-6850.casb2020-0607 Abstract + ( 355 )   HTML ( 6 )   PDF ( 1084KB )   ( 126 ) The paper aims to select high efficient ecology and economic plants suitable for planting in the coastal saline-alkali land of the Yellow River Delta, establish their reasonable planting years and provide technological support for biological management of saline-alkali land. NyPa forage was planted in the heavy saline-alkali wasteland of the Yellow River Delta Horse Farm Base in Hekou District of Dongying City, and the saline-alkali wasteland was taken as the control to explore the soil improvement effect of plants with different planting years. The results showed that: (1) compared with the wasteland of the same period, the soil physicochemical properties of NyPa forage planted for three, six and nine years were greatly improved, which were manifested by the obvious decrease of soil density, salinity and pH value, and significant increase of soil total porosity, organic matter content, available nitrogen content and available phosphorus content, and these seven soil factors were significantly different from those of the same period of the wasteland (P<0.05); while the available potassium content was on the contrary, the content of potassium ions in NyPa grassland was always lower than that in wasteland at the same period, which did not increase the content of potassium ions in soil.(2) with the increase of planting years, the soil physicochemical indexes (soil density, salinity, pH value, total porosity, organic matter content, available nitrogen content and available phosphorus content) of NyPa forage showed a continuous improvement trend, the results of variance analysis also showed that the above soil physicochemical indexes were significantly different in the three time periods of three, six and nine years after planting NyPa forage compared with those before planting (P<0.05), and there were also significant differences between three years’ planting and six and nine years’ planting, but there was no significant difference between six years’ planting and nine years’ planting. Therefore, planting NyPa forage could not only accelerate the process of improving the environmental condition of saline-alkali land, but also have obvious effect from the economic and ecological point of view, the suitable planting period is 5-6 years.

  Effects of Different Levels of Organic Fertilizer on Wheat Yield and Soil Fertility Han Bao, Yu Yueyue, Zhu Wen, Xu Kai, Guo Ning 2021, 37 (24):  73-78.  DOI: 10.11924/j.issn.1000-6850.casb2020-0681 Abstract + ( 348 )   HTML ( 4 )   PDF ( 1133KB )   ( 122 ) To study the effects of different levels of organic fertilizer on wheat yield and soil fertility, a field plot experiment was conducted in Fangshan, Beijing. We set up 6 treatments, which were blank control (CK), application of 0.5 times organic fertilizer (0.5 ON), application of organic fertilizer with equal nitrogen amount of conventional fertilization (ON), application of 1.5 times organic fertilizer (1.5 ON), application of 2 times organic fertilizer (2 ON), and application of 3 times organic fertilizer (3 ON). Long-term positioning test results showed that the yield of wheat treated with 3 times organic fertilizer (3 ON) was the highest, and was at a relatively high level in the past 5 years, which had the greatest impact on the number of ears, grains per panicle and 1000-grain weight per hectare. The application of organic fertilizer significantly increased soil organic matter, available nitrogen, phosphorus, potassium and microbial biomass. Among all the treatments, the application of 1.5 ON and 3 ON had the most obvious effects on soil organic matter, total nitrogen and available phosphorus. The application of different levels of organic fertilizer could increase the soil microbial carbon and urease content. The effect of 1.5 ON treatment on urease content was the most significant, the effect of 3 ON treatment on soil microbial carbon was the most significant, and the application of different levels of organic fertilizer could increase the ratio of 0.01-0.05 mm particle size. The study shows that 3 ON treatment is worth popularizing in wheat production.

  Effects of Straw Buried Deep on Invertase Activity in Soil with Different Nitrogen Fertilizer Levels Xie Hongbao, Yu He, Chen Yimin, Sui Yueyu, Jiao Xiaoguang 2021, 37 (24):  79-83.  DOI: 10.11924/j.issn.1000-6850.casb2021-0166 Abstract + ( 509 )   HTML ( 11 )   PDF ( 1131KB )   ( 213 ) To explore the changing law of soil invertase activity and the response to different nitrogen levels after returning straw to field, the test adopted a split zone test design with two factors of no straw and straw buried deep, and each factor had 4 nitrogen levels (0, 135, 180 and 225 kg/hm2). The results indicated that the soil invertase activity showed a trend of first increasing and then decreasing with the extension of the corn growth period, reached the highest in the jointing stage, gradually decreased in the harvest period, and reached the lowest in the harvesting stage. Compared with the no straw returning treatment, the straw buried deep treatment could significantly increase the soil invertase activity, and with the increase of nitrogen fertilizer level, it could significantly increase the soil invertase activity (P<0.01), when nitrogen application level was 180 kg/hm2, the activity of soil invertase reached the highest value, which was 329.09 mg/(g·24 h), and the increase rate was up to 19.83%. Adding nitrogen fertilizer under the straw buried deep treatment could increase the content of soil organic matter. The amount of soil organic matter reached the highest level of 37.08 g/kg at the fertilizer application level of 180 kg/hm2. Through correlation analysis, it concluded that the interaction between straw buried deep and nitrogen application level had a significantly positive correlation with organic matter content and soil invertase activity, and soil invertase activity had the possibility of reflecting the dynamic changes of soil organic matter content. Therefore, the straw buried deep has beneficial effect on the content of soil invertase, and the activity of soil invertase could be used as one of the nutrient indexes to characterize the content of soil organic matter.

  The Effects of Different Organic Acids on Mobilizing Mineral Elements in Yellow Cinnamon Soil: A Comparative Study Chen Hanying, Zhu Yiwei, Ge Gaofei 2021, 37 (24):  84-90.  DOI: 10.11924/j.issn.1000-6850.casb2020-0691 Abstract + ( 414 )   HTML ( 5 )   PDF ( 1224KB )   ( 72 ) To investigate the effects of different organic acids on mobilizing mineral elements in yellow cinnamon soil, tea polyphenol (TP) and low molecular weight organic acids (LMWOAs) with 10 mmol/L were used to study the difference of mobilization effects among mineral elements by soil extraction test. The results showed that the mobilization order of LMWOAs on Ca and Mg in yellow cinnamon soil was: tartaric acid > citric acid > acetic acid > oxalic acid. Oxalic acid showed strong mobilization ability on Fe, Mn, Cu and Zn, and the mobilization ability of oxalic acid on Fe and Cu were significantly stronger than that of other LMWOAs. The mobilization ability of citric acid on Mn was significantly higher than that of TP and other LMWOAs; the mobilization ability of tartaric acid on Zn was significantly higher than that of TP and other LMWOAs; the mobilization ability of acetic acid on Fe, Mn, Cu and Zn were significantly lower than that of TP and other LMWOAs. TP showed significantly lower mobilization ability on Ca, Mg, Fe, Mn and Zn compared with LMWOAs (except acetic acid), but the mobilization ability of TP on K and Cu were significantly higher than that of LMWOAs. Therefore, planting tea tree could accelerate the mobilization and migration of K and Cu (especially for K) in yellow cinnamon soil, improve the bioavailability of mineral elements while cause soil K deficiency and soil acidification.

  The Function, Structure and Regulation of Microbial Community in Biofloc: A Review Luo Wanyi, Lei Zexiang, Li Yiyong 2021, 37 (24):  91-96.  DOI: 10.11924/j.issn.1000-6850.casb2020-0537 Abstract + ( 393 )   HTML ( 5 )   PDF ( 1088KB )   ( 518 ) To further explore the nature of the biofloc, and promote the development and application of the biofloc technology, this paper analyzes the three aspects of the biofloc: the function, the structure and the artificial regulation. It is concluded that an artificial regulation of the microbial community structure in the aquacultural water can be achieved by the condition adjustment, such as carbon source type, carbon-nitrogen ratio, temperature, pH, dissolved oxygen and etc., so as to attain the purification of the aquacultural water, the biocontrol of the aquacultural species and the improvement of feed utilization rate. And it is pointed out that the interaction among the microflora and the dynamic changes of species and its precise regulation should be studied more deeply.

  Brassin-A Natural Plant Growth Regulator: Biological Activity and Application Song Weifeng, Wei Qinghui, Liu Kai, Lai Yongcai 2021, 37 (24):  97-101.  DOI: 10.11924/j.issn.1000-6850.casb2020-0619 Abstract + ( 826 )   HTML ( 11 )   PDF ( 1133KB )   ( 1084 ) Natural brassin belongs to the endogenous bioactive substances of steroidal plant, with sterols as the backbone. Brassinolide has the strongest biological activity in natural brassin, which is known as the sixth group of plant hormones, and it is highly effective, broad-spectrum and non-toxic plant growth regulators (PGR). In order to promote the application of brassinolide in agricultural production, this paper reviewed the biological activity and the application of brassinolide in crops, such as grain, fruits and vegetables. The research situation and progress of brassinolide were concluded, including improving seed vigor, promoting crop growth, increasing the yield and quality, improving crops resistance, and mitigating the impact of pesticides on crops. The study points out that the application of brassinolide is the key way to increase crop production and income. At the same time, it could reduce the usage amount of fertilizers and pesticides, decrease crop planting cost and environmental pollution, and will bring significant economic benefits.

  Response of Sugarcane Leaves to the Infection of Puccinia melanocephala: Transcriptomic Analysis Gao Xiaoning, Wu Zilin, Huang Yonghong, Liu Rui, Qi Yongwen 2021, 37 (24):  102-109.  DOI: 10.11924/j.issn.1000-6850.casb2020-0622 Abstract + ( 352 )   HTML ( 7 )   PDF ( 1939KB )   ( 74 ) The aim is to analyze the gene expression patterns of sugarcane leaves in response to the infection of P. melanocephala, and to provide data for further research on the molecular mechanism of sugarcane resistance to brown rust. The healthy and infected sugarcane leaves by P. melanocephala were sequenced at transcriptomic level using high-throughput sequencing platform, Illumina Hiseq 2500. The functional annotation and analysis for the differentially expressed genes (DEGs) was carried out with bioinformatics methods. The relative expression levels of five DEGs were further verified by real-time fluorescence quantitative PCR (qRT-PCR). The transcriptome data showed that 4716 DEGs were obtained, including 2979 up-regulated and 1737 down-regulated DEGs. GO annotation results showed that DEGs mainly gathered in the physiological and biochemical processes of cell process, biological process, and catalytic activity, etc. KEGG enrichment analysis revealed that 1919 DEGs were annotated into 114 pathways. The relative genes in the metabolic pathways related to plants’ resistance to biotic stress were significantly up-regulated, and these metabolic pathways included phenylpropane biosynthesis, flavonoids biosynthesis, and glutathione metabolism and so on. In addition, the qRT-PCR results confirmed that the expression profiles of five up-regulated genes were consistent with that of transcriptome sequencing.

  Ion Changes and Transcriptome Analysis of Maize Under Salt Stress Zhu Yongxing, Guan Yajing, Li Xin, Zhang Chunyi 2021, 37 (24):  110-115.  DOI: 10.11924/j.issn.1000-6850.casb2020-0452 Abstract + ( 425 )   HTML ( 4 )   PDF ( 1430KB )   ( 85 ) The aims are to study the ion changes and the response of functional genes in maize under salt stress, and lay a foundation for the cultivation of salt-tolerant maize varieties in the future. Four maize inbred lines were used as materials and were treated with 200 mmol/L NaCl solution for 14 days. The contents of Na+, K+, Ca2+ in underground and aboveground parts were determined and analyzed. Meanwhile, the transcriptome analysis was carried out to study the expression of functional genes in maize under salt stress. The results showed that among the four inbred lines, S388 had the lowest Na+ content and Na+ accumulation in leaves and roots. At the same time, the Na+:Ca2+ ratio of S388 was the highest among the four materials. The transcriptome analysis showed that S388 was involved in ion transport pathway, stress signal and ion transmembrane transport. The results indicated that the salt tolerance of S388 was the highest among the four maize inbred lines, and there was less Na+ content in leaves and roots, which provided a material basis for breeding salt-tolerant varieties in the future.

  Analysis of Bacterial Community in Ganoderma lingzhi Continuous Cropping Soil Based on 16S rDNA Amplicon Sequencing Yuan Yuan, Li Lin, Huang Haichen, Liu Guohui, Xie Fuquan, Fu Junsheng, Wu Xiaoping 2021, 37 (24):  116-123.  DOI: 10.11924/j.issn.1000-6850.casb2020-0474 Abstract + ( 443 )   HTML ( 4 )   PDF ( 1887KB )   ( 1173 ) This study aims at revealing the changes of bacterial community in the covering soil of Ganoderma lingzhi with different continuous cropping years, and providing a theoretical basis for the study of continuous cropping obstacle mechanism of Ganoderma lingzhi. Taking the adjacent sandy soil (GL0) as the control, Illumina MiSeq platform was used for the amplicon sequencing of the covering soil of Ganoderma lingzhi cultivated for 1 year (GL1), and continuous cropped for 1 year (GL2), 2 years (GL3), and 3 years (GL4). The diversity analysis showed that continuous cropping increased the difference in species composition of bacterial communities in the covering soil of Ganoderma lingzhi, and the abundance and diversity of bacterial communities showed a tendency of increasing first and then decreasing. At the level of phylum, the relative abundance of Proteobacteria and Actinomycetes increased significantly with the increase of continuous cropping years, while that of Chloroflex decreased. At the genus level, the relative abundance of Sphingomonas, Anaeromyxobacter, Bradyrhizobium, Dehalococcoides and Ktedonobacter in the covering soil of Ganoderma lingzhi reduced year by year; while that of Lysobacter, Gp6 and Gp16 dramatically increased. Continuous cropping obstacle of Ganoderma lingzhi may be related to the year-by-year decrease of the relative abundance of beneficial bacteria such as Sphingomonas, Anaeromyxobacter, Bradyrhizobium and Dehalococcoides and so on in covering soil.

  Interspecific Relationship of Lactobacillus paracasei Co-cultured with Bacillus sp. Affects Bacteriocin Production Jiang Xueyong, Yue Yuanchun, Sun Yangcun, Gao Dongni, Ping Wenxiang, Ge Jingping 2021, 37 (24):  124-132.  DOI: 10.11924/j.issn.1000-6850.casb2020-0724 Abstract + ( 513 )   HTML ( 7 )   PDF ( 1778KB )   ( 697 ) To form a stable ecological environment through interspecific information exchange between Lactobacillus paracasei HD1.7 and Bacillus sp., the initial inoculation amount of Bacillus sp. was increased to study the ecological relationship of Lactobacillus paracasei co-cultured with Bacillus sp.. When Bacillus subtilis was co-cultured with L. paracasei HD1.7 at the initial inoculation ratio of 5%:1%, the bacteriocin produced by L. paracasei HD1.7 was 1.21 times that of monoculture. L. paracasei HD1.7 quorum sensing-related genes luxS, prcK, and prcR were upregulated (up to 3.14, 4.98 and 5.41 folds, respectively) while B. subtilis formed more spores to avoid the attack of bacteriocins. Expression levels of spo0A, sigE, sigF, and sigG, genes related to B. subtilis endospore formation, were correspondingly upregulated (up to 2.37, 2.71, 3.15 and 2.56 folds, respectively). At this time, a cooperative ecological relationship was formed between L. paracasei HD1.7 and Bacillus sp.. The redundancy analysis revealed that the number of spores, incubation time and B. subtilis viable counts were the most closely related to the production of bacteriocin. Different ecological relationships were found between L. paracasei HD1.7 and Bacillus sp., and some Bacillus are beneficial to L. paracasei HD1.7 and some are harmful to it.

  Formula of Tomato Seedling Substrate Based on Pleurotus ostreatus Mushroom Bran as the Main Raw Material Wang Qinli, Yan Fang, Han Yuqi, Shan Huajia, Song Liru, Feng Yueqin, Wang Zhiwei, Wei Shenglong 2021, 37 (24):  133-138.  DOI: 10.11924/j.issn.1000-6850.casb2020-0702 Abstract + ( 338 )   HTML ( 4 )   PDF ( 1221KB )   ( 45 ) To screen the suitable substrate formula for tomato seedling, Hypsizygus marmoreus mushroom bran, peat, perlite, and vermiculite were made into 4 different seedling substrates with different proportions. Taking tomato variety ‘6629’ as the indicator variety and the peat seedling matrix of Rexwang Company of the Netherlands as the control (CK), the randomized block design was used to carry out the plug seedling test. The results showed that the bulk density of the seedling matrix of T4 (mushroom residue: peat: perlite: vermiculite = 5:3:1:1) formula was 0.2045 g/cm 3, the total porosity was 68.17%, and the water holding porosity was 61.51%, in line with national industry nursery matrix standards. The aeration porosity was 6.66%, and the gas-water ratio was 0.1083, which was lower than the industry standard. The pH was 7.61, available nitrogen was 821.80 mg/kg, available phosphorus was 353.00 mg/kg, available potassium was 16.11 mg/kg, organic matter was 477.9 mg/kg, all were higher than the industry standard. The plant height was 2.96 cm, the stem diameter was 0.24 cm, the root length was 14.61 cm, the ground fresh weight was 22.8913 g, the underground fresh weight was 3.8272 g, the ground dry weight was 3.3364 g, the underground dry weight was 0.9124 g, the strong seedling index was 2.9368, the root-shoot ratio was 0.2735, and the bulk lump rate was 0 of tomato seedlings bred by T4 formula. The average value of membership function was 0.5961, second only to the control. All indicators of T4 (mushroom residue: peat: perlite: vermiculite = 5:3:1:1) formula were close to those of the control (CK), which could be the substrate for tomato seedling.

  Methomyl: Pollution Status and Its Toxic Effect on Aquatic Organisms Lu Yan, Meng Shunlong, Chen Jiazhang 2021, 37 (24):  139-145.  DOI: 10.11924/j.issn.1000-6850.casb2020-0006 Abstract + ( 400 )   HTML ( 6 )   PDF ( 1122KB )   ( 912 ) Methomyl is a kind of carbamate pesticide, which can be used as insecticide, fungicide and herbicide. It has the characteristics of strong selectivity, high efficiency, easy decomposition and degradation, and is widely used in agriculture and forestry. In order to explore the pollution status and severity of methomyl, the authors review the current research status of methomyl, and systematically summarize the domestic and foreign study cases of toxic effects of methomyl, mainly focus on the application and pollution status of methomyl, its reproductive toxicity effect on aquatic organisms, tissues and organs, and DNA damage, etc. At last, the authors discuss the future research directions of methomyl, aiming to provide referential data for further understanding its present pollution situation and toxic effect on aquatic organisms.

  Citrus Bacterial Canker Disease: Pathogen Identification and Bactericides Screening Li Ya, Cai Yongjun, Yu Qinhan, Kong Shaolian, Zhou Xiaoqing, Zhang Yinghe 2021, 37 (24):  146-153.  DOI: 10.11924/j.issn.1000-6850.casb2020-0628 Abstract + ( 531 )   HTML ( 11 )   PDF ( 1951KB )   ( 338 ) The purpose of this study is to identify the pathogen types of citrus bacterial canker disease in Zhanjiang area and screen effective bactericides. Lemon leaves were used as materials, and the strains were isolated and identified by tissue separation. The indoor toxicity of five bactericides to this pathogen was determined by inhibition zone test. The colony morphology of classic strain zlm1908 on nutrient agar medium (NA) was wax yellow, circular, entire, glistening, convex and mucoid. Citrus canker disease symptoms appeared obviously after reinoculating healthy lemon leaves. The strain zlm1908 was identified as Xanthomonas citri subsp. citri (Xcc) by physiological and biochemical reaction, specific primer amplification and sequence analysis. The EC50 of five bactericides was 18.45 g/L, 14.99 g/L, 5.28 g/L, 14.60 g/L and 32.81 g/L, respectively. According to the analysis of EC50 value, the inhibiting effect of Bacillus subtilis is the strongest among the five bactericides, followed by zhongshengmycin, copper dihydroxosulphate, copper hydroxide, while chlorobromoisocyanurate has the least inhibiting effect.

  Antifungal Activity of 21 Natural Products Against Wheat Root Rot Fungus Zhang Bo, Zhang Yueli, Ma Liguo, Qi Kai, Liu Ping, Li Changsong, Qi Junshan 2021, 37 (24):  154-158.  DOI: 10.11924/j.issn.1000-6850.casb2020-0601 Abstract + ( 606 )   HTML ( 8 )   PDF ( 1677KB )   ( 570 ) This study aims at exploring biological control of wheat root rot, screening effective natural antifungal substances, and achieving the purpose of fungicide reduction. Using Fusarium graminearum, Pythium spinosum and Bipolaris sorokiniana as materials, the antifungal activities of 21 natural products were determined by mycelial growth method. The results showed that the trans-asarone and cis-asarone had significant effects on Fusarium graminearum, the EC50 was 69.99 mg/L and 130.23 mg/L, respectively. Resveratrol, cis-asarone and lemon essential oil had obvious antifungal activity against Pythium spinosum, the EC50 was 24.4683 mg/L, 71.02 mg/L and 79.83 mg/L, respectively. Eugenol and resveratrol had significant effects on Bipolaris sorokiniana, the EC50 was 14.06 mg/L and 22.09 mg/L, respectively. Therefore, eugenol, trans-asarone, cis-asarone, lemon essential oil and resveratrol could effectively inhibit the pathogenic growth of wheat root rot, which have great potentials in biological control of wheat root rot.

  The Evaluation of Growth Performance of Three Largemouth Bass Strains Based on Indoor Recirculating Aquaculture System Zhou Fan, Peng Jian, Chen Liupu, Zhu Ningyu, Yao Gaohua, Bei Yijiang, Ma Wenjun, Ding Xueyan 2021, 37 (24):  159-164.  DOI: 10.11924/j.issn.1000-6850.casb2020-0444 Abstract + ( 425 )   HTML ( 4 )   PDF ( 1190KB )   ( 85 ) The present trial was conducted to evaluate the growth performance of three largemouth bass Micropterus salmoides strains based on indoor recirculating aquaculture system. M. salmoides juveniles of the three stains, including ‘Youlu No.1’, ‘Youlu No.3’ and ‘Zhelu No.2’ were assigned randomly into 9 tanks with triplicate tanks for each stain respectively. Each tank had 30 fish (initial body weight 6.08±0.12g) and the feeding trial lasted 8 weeks. The results showed that the survival rate was all above 98.89% (P>0.05); the body weight gain ranked as ‘Youlu No.3’>‘Youlu No.1’>‘Zhelu No.2’ without significant differences (P>0.05); while the lowest variable coefficients of body length and weight were both observed in ‘Zhelu No.2’(P>0.05). The morphological indices among the three strains showed no significant differences (P>0.05). The higher feed coefficient rate and protein efficiency ratio were found in ‘Zhelu No.2’ and ‘Youlu No.3’, respectively (P<0.05). There was no significant difference of dorsal muscle composition and amino acids’ content among the three stains (P>0.05). The activities of trypsin in gut and liver were significantly lower in ‘Zhelu No.2’ than those in other stains (P<0.05). Ten parameters contents in serum maintained stability and no statistic difference existed among the three stains (P>0.05). The data generated from the current trial suggest that M. salmoides is an appropriate fish species for indoor recirculating aquaculture, and ‘Youlu No.3’ shows relative better growth performance in the present system. ‘Zhelu No.2’ also shows very considerable body weight gain, nutrient composition as well as resistance when compared with ‘Youlu’ stains, providing good potential as a breeding population.