Current issue

• 2020 Vol.36 No.24 Published:25 August 2020

  Xindan Maize Hybrids: Genetic Basis Analysis and Change Trends of Quality and Yield Traits Ma Junfeng, Hong Defeng, Wei Feng, Ma Yi, Wei Xiaoyi, Wang Jiamu, Peng Dong, Tang Zhenhai, Zhang Xueshun 2020, 36 (24):  1-6.  DOI: 10.11924/j.issn.1000-6850.casb20200300171 Abstract + ( 364 )   HTML ( 3 )   PDF ( 1135KB )   ( 50 ) To explore the relationship among grain quality traits and the change trend of yield traits of maize varieties of Xindan series, varieties bred by Xinxiang Academy of Agricultural Sciences since 2003 were used as materials, the genetic basis, heterosis model, quality traits, population and individual productivity of these maize varieties were studied. The results showed that there were two heterosis models for 13 maize varieties. The heterosis model of nine varieties was improved Reid×TSPT, and the heterosis model of four varieties was exotic germplasm ×TSPT. The content of crude starch of ‘Xindan 28’, ‘Xindan 38’ and ‘Xindan 66’ were high, the content of crude protein and lysine of ‘Xindan 61’, ‘Xindan 65’ and ‘Xindan 68’ were high. The crude fat content was negatively correlated with the crude starch content, and reached a significant level, with a correlation coefficient of 0.610. The content of crude protein was positively correlated with that of lysine, and the correlation coefficient was 0.491. The productivity per plant of ‘Xindan 22’ was the highest, while that of ‘Xindan 33’ was the lowest. The population productivity of ‘Xindan 58’ was the largest, while that of ‘Xindan 28’ was the lowest. The population productivity was increased with the density increase, among which the population productivity of 75000 plants/hm2 was 62.9% higher than that of 45000 plants/hm2, and the yield gain of an average increase of 7500 plants/hm2 was 12.97%. The population per plant began to decline with the density increase, after the increase reached 60000 plants/hm2, the growth was gradually gentle. The productivity per plant in the low-density group was 5.5% higher than that in the high-density group. The quality of maize varieties of Xindan series bred by the heterosis model of exotic germplasm × TSPT was better than that of the improved Reid×TSPT, their resistance to density increased significantly, and the population productivity also increased constantly.

  Spring Maize Varieties (Strains) in Early-maturing Zone in Northeast China: Analysis of High-yield, Stability and Adaptability Gao Xiang, Zhou Xianlin, Yang Hui, Zhou Xinming, Zhang Xijun, Xiang Fuchao 2020, 36 (24):  7-13.  DOI: 10.11924/j.issn.1000-6850.casb20190700478 Abstract + ( 458 )   HTML ( 7 )   PDF ( 1249KB )   ( 59 ) The objective of the study is to screen excellent spring maize varieties in early-maturing zone in northeast China, and provides references for maize production in this region. Five new varieties were used as the test materials and ‘Jidan 27’ was used as control. The high and stable yield, and adaptability of the tested varieties were compared, and statistical analysis of different experimental sites was carried out. The results showed that the average yield of the tested varieties was 9642.8-12663.2 kg/hm2, the yield of ‘XS60’, ‘XS63’ and ‘XS64’ were significantly higher than that of the control, and increased by 4.4%, 6.4% and 3.6%, respectively. The stability of the test varieties by F test had extremely significant difference, the stability of ‘XS63’ and ‘Jidan 27’ were relatively good, ‘XS61’, ‘XS63’, ‘XS64’ and ‘jidan 27’ had the same growth period, 100 grain weight of ‘XS63’ was the highest, the seed rate of ‘XS62’, ‘XS63’ and ‘Jidan 27’ were more than 80%, the empty stalk rate of ‘XS61’ and ‘XS63’ were less than that of ‘Jidan 27’. In summary, spring maize variety ‘XS63’ has outstanding comprehensive characteristics, high-yield, stability and adaptability, which could be further applied and popularized in early-maturing region in northeast China.

  Matrix-based Nitrogen Fertilizers with Different Matrix-material Doses: Effects on Ammonia Volatilization and Nitrogen Use Efficiency in Maize Field Yang Yang, Ni Xiaoyu, Liu Binmei, Tao Liangzhi, Yu Lixiang, Yang Ye, Feng Mengxi, Zhong Wenjin, Wu Yuejin 2020, 36 (24):  14-22.  DOI: 10.11924/j.issn.1000-6850.casb20190600354 Abstract + ( 241 )   HTML ( 8 )   PDF ( 1308KB )   ( 46 ) The paper aims to explore the effects of matrix-based nitrogen fertilizers with different matrix-material doses on ammonia volatilization and nitrogen use efficiency in the maize field. We set up 8 treatments including the control test, common nitrogen fertilizer, and 6 matrix-based nitrogen fertilizers (with 1%-6% matrix-materials, at a 1% interval) to measure the ammonia volatilization, soil inorganic nitrogen, maize yield and yield components, plant nitrogen uptake, nitrogen physiological efficiency, nitrogen recovery efficiency, and nitrogen agronomical efficiency and so on in the field. The results showed that: the total ammonia volatilization in matrix-based nitrogen fertilizer treatments in the field was 9.5%-45.9% lower than that in regular nitrogen fertilizer treatment; the ammonia volatilization in the field decreased with the increase of matrix-material dose; compared with regular nitrogen fertilizer treatment, matrix-based nitrogen fertilizer treatments with 2%-6% matrix-materials significantly increased soil inorganic nitrogen at silking stage by 7.1%-17.8%, grain yield by 5.2%-19.4%, nitrogen recovery efficiency by 21.1%-55.0%, and nitrogen agronomical efficiency by 22.5%-38.1%. Overall, the application of matrix-based nitrogen fertilizers with ≥2% matrix-materials could reduce ammonia volatilization in the maize field, increase maize grain yield, and improve the nitrogen use efficiency.

  Maize Optimal Fertilization Technology: Application and Research Based on TRPF System Wang Nannan 2020, 36 (24):  23-27.  DOI: 10.11924/j.issn.1000-6850.casb20200200098 Abstract + ( 155 )   HTML ( 6 )   PDF ( 976KB )   ( 31 ) To verify the application effect of TRPF (Three River Plain Fertilizer Recommendation System) on soil testing and formulated fertilization of maize, using maize variety ‘ZheDan 37’ as the material, through setting up different fertilization treatments, related traits, yield and other items of maize were analyzed by SPSS. The results showed that under the TRPF treatment, the spike length, spike line number, grain line number, spike thickness and grain weight per plant had the best performance. There was no significant difference between TRPF treatment and RF (routine fertilization treatment), but there was significant or extremely significant difference between TRPF treatment and other treatments. There were significant or extremely significant differences in maize yield between different fertilization treatments. TRPF treatment had the highest yield in the five treatments and it had significant differences with LR (lower fertilization treatment) and CK (control treatment). HR (higher fertilization treatment) had the largest amount of fertilizer input of 2564.0 yuan/hm2, and according to the price of maize at 1.2 yuan/kg, the net benefit of TRPF treatment was the highest at 13246.2 yuan/hm2. From the perspective of income per hectare, TRPF treatment increased revenue by 2314.2 yuan compared with CK (control treatment), 1458.2 yuan compared with HF, 771.2 yuan compared with LF (lower fertilization treatment), and 800.2 yuan compared with RF (routine fertilization treatment). This study verifies the good effect of TRPF system from the perspectives of agronomic trait, yield, fertilizer input and so on. In other words, TRPF system could achieve the effect of fertilizer reduction in maize production and good economic benefit.

  Changes of Grain Quality Characters of Sweet Maize at Different Harvesting Periods Lu Baishan, Dong Hui, Xu Li, Shi Yaxing, Zhao Jiuran, Fan Yanli, Yu Ainian 2020, 36 (24):  28-33.  DOI: 10.11924/j.issn.1000-6850.casb20190800514 Abstract + ( 278 )   HTML ( 6 )   PDF ( 1216KB )   ( 55 ) Seven main sweet maize varieties in China were used as research materials, and six harvesting periods were set up at 15, 18, 21, 24, 27 and 30 d after pollination to study the effect of different harvesting periods on the quality traits of sweet maize. The water content, pericarp thickness and sugar composition in sweet corn were monitored dynamically. The results showed that: (1) grain moisture content of the tested sweet maize varieties decreased at 15-30 d after pollination, the change ranging from 80.09% to 68.76%; the grain water content of ‘Jingketian 608’, ‘Jingketian 533’ and ‘Zhongnongdatian 413’ decreased slowly; (2) the pericarp thickness of sweet maize varieties increased first and then decreased with the time after pollination, and the peak appeared about 21 days after pollination; the average pericarp thickness of ‘Zhongnongdatian 413’ was the highest among the tested varieties, 91.63 μm, and that of ‘Jingketian 608’ and ‘Mige’ were the lowest, 78.40 μm; (3) the content of glucose and fructose in the grains decreased at 15-30 d after pollination, the content of glucose and fructose of ‘Jingketian 533’, ‘Jingketian 183’ and ‘Jingketian 608’ were relatively high at 15-24 d after pollination; the sucrose and sorbitol content increased first and then decreased with the time after the pollination, the sucrose content of ‘Jingketian 158’ and ‘Mige’ were relatively high among different varieties at 21-30 d after pollination. At the grain early development stage (before 21 days after pollination), fructose and glucose were the main sugars in grains, and then sucrose gradually increased. Among different varieties, the total sugar content of ‘Jingketian 533’, ‘Jingketian 183’, ‘Zhongnongdatian 413’ and ‘Jingketian 608’ were higher than that of ‘Mige’. The main sugar components were fructose and glucose, while the sucrose content was relatively low.

  Effects of Fertilization Methods on Fruit Yield and Appearance Quality of Citrus ‘Orah’ Yang Shoushan, Zhu Zhijun, Guo Yingyun, Chen Xinquan, Yang Zezhong, Yang Meiqiong, Chen Guoxi, Zhou Mingde, Li Xuewen, Li Xia, Huang Bangchi, Huang Shaowei 2020, 36 (24):  34-41.  DOI: 10.11924/j.issn.1000-6850.casb20200300230 Abstract + ( 279 )   HTML ( 4 )   PDF ( 1255KB )   ( 50 ) To verify the effect of soil testing and formula fertilization, promote the reduction and efficiency of chemical fertilizer, and explore the effect of organic fertilizer, medium and trace element fertilizer combined with chemical fertilizer on the fruit production and the appearance quality of Citrus ‘Orah’, a precision experiment of random block plot was set up. The experimental treatments included local conventional fertilization, recommended fertilization for soil test formula, optimized fertilization, optimized fertilization and foliar spraying with 0.2% boric acid, optimized fertilization and foliar spraying with 0.05% ammonium molybdate, optimized fertilization and foliar spraying with 4% magnesium sulfate. The results showed that the recommended fertilization of soil testing formula was more effective than that of conventional fertilization. There was no significant difference in yield between the treatment of organic fertilizer instead of partial chemical fertilizer and the treatment of total chemical fertilizer under the same nutrient application, but the fertilizer efficiency of the former was increased by 4.03% compared with that of the latter. Under the lacking of soil exchangeable magnesium, the magnesium application on the leaf of Citrus ‘Orah’ could obtain a significant and stable increase effect on the yield. Without lacking of soil boron, the application of boron on leaf might be ineffective. When the available molybdenum in the soil was insufficient, the foliar application of molybdenum could increase the yield of Citrus ‘Orah’, but the effect of continuous application was not stable. It can be seen that with the improvement of fruit appearance quality, it is feasible to reduce the amount of chemical fertilizer and increase the efficiency in the production of Citrus ‘Orah’; the yield increase potential under fertilization is large, and appropriate fertilization formula can bring more benefits.

  Effects of Chemical Fertilizer Reduction Combined with Organic Fertilizer Application on Growth, Fruit Yield and Quality of Lemon Trees Liu Hongming, Long Chunrui, Pan Yanhua, Fu Xiaomeng, Mao Jiamei, Du Yuxia, Yue Jianqiang, Li Jinxue 2020, 36 (24):  42-46.  DOI: 10.11924/j.issn.1000-6850.casb20190800541 Abstract + ( 292 )   HTML ( 4 )   PDF ( 1182KB )   ( 36 ) The research aims to improve the soil quality, reduce the use of chemical fertilizer, and improve the yield and quality of lemon fruit by chemical fertilizer reduction combined with organic fertilizer application, thus to provide a technical basis for soil environment improvement and fertilizer reduction and efficiency increase in lemon plantations in Yunnan. We used ‘Yunning No.1’ as the test material and carried out a field plot experiment, four different fertilization treatments were set up, namely 100% chemical fertilizer(conventional fertilization), 70% chemical fertilizer (30% reduction)+15 kg/tree organic fertilizer, 50% chemical fertilizer (50% reduction)+15 kg/tree organic fertilizer and no chemical fertilizer+15 kg/tree organic fertilizer (control group), to measure relative indexes of lemon growth, bloom and fruit-setting, fruit quality, yield and chlorophyll content. The results showed that there were significant differences between 100% chemical fertilizer and 70% chemical fertilizer with organic fertilizer in plant height, stem diameter, yield and fruit quality. The treatment of 70% chemical fertilizer with organic fertilizer significantly promoted the plant growth, and achieved higher yield and quality. Compared with 100% chemical fertilizer, the plant height increased by 6.37%, stem diameter(up and down of the graft union 5 cm) increased by 13.05% and 9.61%, fruit weight and yield per plant increased by 15.19% and 28.60%, juice yield, vitamin C and total sugar content of lemon fruit increased by 6.68%, 27.85% and 6.20%, respectively. Comprehensively considering the yield and quality, the treatment has the best effect of yield increase, quality improvement and efficiency enhancement.

  Interannual Dynamic Changes of Groundwater in Takyric Solonetz Land: Characteristics Study Yang Jun, Sun Zhaojun 2020, 36 (24):  47-53.  DOI: 10.11924/j.issn.1000-6850.casb20190700489 Abstract + ( 144 )   HTML ( 3 )   PDF ( 1234KB )   ( 32 ) In order to provide a theoretical basis for salt-water management of the takyric solonetz farmlands, in this study, the depth of groundwater was measured by rope method, mineralization was detected by conductivity meter, pH was determined by multi-parameter meter and salt ions were measured by titration method. The variation of the depth, mineralization and salt ion of groundwater of takyric solonetz farmlands were compared and analyzed. The results showed that the horizontal changes of the depth of groundwater and mineralization were great, and the variation coefficients were 22.2% and 38.9%, respectively. The horizontal variations of salt ion Na+, Cl-, and HCO3- were relatively great, while Ca2+ and K+ had less variation. Groundwater salt ions were mainly Na+, Cl–, SO42- and HCO3-. Groundwater depth became shallow year by year, pH and mineralization became smaller year by year. These results provide a technical support for salt-water management of the takyric solonetz farmlands, and have important scientific value for environmental protection and agricultural irrigation in arid areas.

  Micro-fertilizers: Effects on the Properties of Super Absorbent Polymer Synthesized by Nuclear Technology Wei Min, Luo Longxin, Yang Pinghua, Yan Qinghai, Liu Ying 2020, 36 (24):  54-58.  DOI: 10.11924/j.issn.1000-6850.casb20190700434 Abstract + ( 152 )   HTML ( 2 )   PDF ( 1133KB )   ( 31 ) To explore the effect of micro-fertilizers on the properties of super absorbent polymer (SAP) developed by the Institute of Biotechnology and Nuclear Technology, Sichuan Academy of Agricultural Sciences, the SAP was tested by six kinds of micro-fertilizer solutions with agricultural concentration and saturated concentration, the change of properties and morphological structure of SAP were observed through repeated water absorption tests. The results showed that borax and ammonium molybdate solution had little effect on the morphological structure of SAP. The other four kinds of bivalent metal micro-fertilizer solutions could destroy the structure of SAP in varying degrees, and the shape of SAP was changing from granular to schistose. The water absorbency of SAP for inhaled micro-fertilizers were decreased and showed the color of the micro-fertilizers, but most of the water absorbency could be gradually increased under the treatment of deionized water. The water absorbency of SAP with borax and manganese sulfate saturated solution treatments were 78.2 g/g and 4.83 g/g, then through deionized water treatments, the water absorbency reached 347 g/g, 277 g/g. During the 0.2% zinc sulfate and copper sulfate solution treatments, the water absorbency was 74.4 g/g and 60.0 g/g, respectively. After deionized water treatments, they reached 367 g/g and 232 g/g. Therefore, micro-fertilizers can reduce the water absorbency and accelerate the degradation rate of SAP, but it can still play the role of water and fertilizer retaining. In order to improve the utilization ratio of soil water and fertilizer, suitable concentrations of micro-fertilizers are better applied together with this SAP.

  Land Carrying Capacity of Livestock and Poultry Manure in Nan’an Based on Nitrogen Balance Chen Zejin 2020, 36 (24):  59-62.  DOI: 10.11924/j.issn.1000-6850.casb2020-0270 Abstract + ( 211 )   HTML ( 3 )   PDF ( 1113KB )   ( 40 ) In order to study the feasibility of constructing the national level "Whole County-wide Promotion Project" for the resource utilization of livestock and poultry manure in Nan'an, the land carrying capacity of livestock and poultry manure was studied by analyzing the supply of manure nitrogen nutrients and the demand for nitrogen nutrients of crops based on the statistics of various crop yields and livestock storage in 2018. The results showed that the land carrying capacity of livestock and poultry manure was 659361 pig equivalent, which was 153758 pig equivalent more than the actual stock of livestock. Therefore, using the whole manure fertilizer in local area is feasible.

  Forage Planting Patterns: Effects on Soil Nutrients in Degraded Farmland Wei Qing, Saijirihu , Wang Jing, Cheng Yucheng, Lu Zhanyuan, Zhang Xiangqian, Li Yahua, Sun Feng, Zhang Dejian 2020, 36 (24):  63-71.  DOI: 10.11924/j.issn.1000-6850.casb20190700372 Abstract + ( 256 )   HTML ( 5 )   PDF ( 1225KB )   ( 34 ) To screen out the optimal forage planting pattern and provide theoretical and technical support for the improvement of degraded farmland and sustainable land use, taking Medicago sativa CV. Aohan and Elymus sibiricus L. as materials, we set 3 different planting patterns: single-seeding Medicago sativa CV. Aohan (Ms), single-seeding Elymus sibiricus L. (Es) and intercropping of these two forage (In), with fallow treatment as the control (CK). The results showed that: with the increase of planting years, the soil available phosphorus content first decreased and then increased; organic matter, available potassium, total nitrogen, total potassium content increased; compared with CK, in the first year, the contents of soil organic matter, available potassium, alkali-hydrolyzed nitrogen and total nitrogen increased under different planting patterns; and the contents of soil total phosphorus and total potassium increased under Ms and In groups; in the second year, the alkali-hydrolyzed nitrogen content of Ms, Es and In decreased by 20.91%-40.05% in 10-20 cm soil layer, and the available phosphorus content decreased by 32.19%-39.65% in 20-40 cm soil layer; the contents of soil organic matter and total potassium increased overall, while the contents of available phosphorus and available potassium decreased; the total phosphorus content decreased significantly in the 20-40 cm soil layer.

  Soil Ecoenzymatic Stoichiometry Characteristics: Natural Influencing Factors and Their Responses to Nitrogen Deposition Wang Lei, Wang Qinggui 2020, 36 (24):  72-77.  DOI: 10.11924/j.issn.1000-6850.casb20190700387 Abstract + ( 637 )   HTML ( 10 )   PDF ( 1109KB )   ( 163 ) Soil enzyme is an important factor affecting the material and energy cycle of soil ecosystem, and it is mainly from microorganisms; microbial extracellular enzyme activity can be used to characterize the soil fertility, and the ratio of C-, N-, P-acquisition enzyme activity (soil ecological enzyme stoichiometric ratio) is the index of nutrient acquisition and energy distribution of soil microorganisms. However, there is less discussion on eco-enzyme stoichiometry. This paper discussed the response of soil ecological enzymes to nitrogen deposition from the perspective of nitrogen deposition, and fully explored the changes of soil ecological enzymes (GLU, NAG, LAP, AP) and Phenol oxidase (PHO) activities under the background of nitrogen deposition; meanwhile, the paper studied the effects of temperature, water content, pH and ecosystem types on the activities of C, N, P-aquisition enzymes in order to provide data support for further study on soil ecological enzymes.

  Climate Suitability of Crops in China: Research Progress Lv Zihe, Ding Songshuang, Lu Ruilin 2020, 36 (24):  78-84.  DOI: 10.11924/j.issn.1000-6850.casb20190700470 Abstract + ( 514 )   HTML ( 6 )   PDF ( 1116KB )   ( 124 ) To discuss the status of climate suitability of crops in China, make better use of climate resources, and provide a theoretical basis for planting plans and protection measures for crops, we summarized the common methods used in the study of climate suitability of crops, and discussed the principles, advantages and disadvantages of each method and the scope of their application; on the basis of this, we reviewed the research progress on the climate suitability of 5 crops, including rice, wheat, corn, cotton and tobacco in China. The results show that: the research on the climate suitability of crops in China has been gradually deepened, and played an important role in making full use of climate resources and rational production measures. MAXENT model, geographic information system, integral regression method, analytic hierarchy process and other technologies have their own advantages and disadvantages. The comprehensive application of these methods and the continuous improvement of new technologies will provide new ideas for the study of climate suitability of crops.

  Exogenous Regulator Substances Regulate Plant Growth Under Salt Stress: A Review Geng Gui, Li Renren, Lv Chunhua, Yu Lihua, Wang Yuguang 2020, 36 (24):  85-90.  DOI: 10.11924/j.issn.1000-6850.casb20200200090 Abstract + ( 371 )   HTML ( 7 )   PDF ( 1110KB )   ( 135 ) To explore the regulation mechanism of exogenous substances on plant salt tolerance and to further utilize exogenous regulatory substances to improve plant salt tolerance, we summarized the five categories of traditional plant hormones (auxin, gibberellin, ethylene, abscisic acid, and cytokinin), and exogenous growth regulators such as melatonin, salicylic acid, polyamine, brassinosteroid, jasmonic acid on plant growth regulation under salt stress. At the same time, we reviewed the regulation effect of silicon and calcium on plant growth under salt stress, indicated that various exogenous regulatory substances could reduce salt damage by enhancing photosynthesis, increasing osmotic potential, improving protecting enzyme activity and reducing ion toxicity. This study provides a theoretical basis for using the single or compound exogenous regulatory substances to alleviate crop salt damage in the future.

  Pyruvate Decarboxylase Gene (pdc1) of Haploid Saccharomyces Cerevisiae: Knockout and Identification Kang Jie, Wang Changli, Ge Jingping 2020, 36 (24):  91-98.  DOI: 10.11924/j.issn.1000-6850.casb20190600332 Abstract + ( 267 )   HTML ( 3 )   PDF ( 1678KB )   ( 45 ) The aim is to inhibit the synthesis of ethanol, a by-product of haploid Saccharomyces cerevisiae H14, and increase the yield of 2,3-butanediol. The vector pWCL-pdc1 was constructed by genetic engineering to obtain the homologous recombinant fragment loxP-kanMX-loxP containing 40 bp pdc1 at both ends. The pdc1 deleted strain S. cerevisiae H14-01 (Δpdc1) was obtained by Cre/loxP technique. The shaking flask fermentation experiment was carried out with the wild type strain S. cerevisiae H14 as the control. The growth of S. cerevisiae H14-01 was significantly lower than that of the original strain. During the whole fermentation period, the maximum yield and conversion rate of 2,3-butanediol were 0.373 ±0.016 g/L and 0.005 g/g, respectively, which were 37.30% and 4.66% higher than that of the original strain, respectively. However, acetoin and 2,3-BD production was not detect in the original strain. In addition, the ethanol conversion of S. cerevisiae H14-01 decreased by 33.24%, but the glycerol production increased by 15.76%. It showed that after the carbon flow to ethanol was blocked, the production of 2, 3-butanediol could be increased, and part of the carbon flow will flow to glycerol. Therefore, the study lays a good foundation for further obtaining an engineering microbial population with high yield of 2,3-butanediol.

  Identification of Different Armillaria spp. Strains and Extracellular Enzyme Activity Liu Xiaomin, Chen Xiangdong, Zhang Weiwei, Wang Zhongqiao, Song Minghai, Lan Jin, Ma Lin 2020, 36 (24):  99-106.  DOI: 10.11924/j.issn.1000-6850.casb20191000716 Abstract + ( 236 )   HTML ( 4 )   PDF ( 1342KB )   ( 41 ) The aim is to identify different Armillaria spp. strains associated with cultivated Gastrodia elata, and to provide a basis for screening the excellent strains by comparing the changes of extracellular enzyme activity and polysaccharide content. In this study, M1, M2, F2, and F3 strains were used as test materials, and the phylogenetic tree was constructed by the combined sequences of ITS, β-tubulin and Tef1-α gene fragments. The extracellular enzyme activity was determined by the ABTS and DNS method. The mycelial polysaccharide content was determined by the phenol-sulfuric acid method. According to phylogenetic analysis, the M1 and M2 strains isolated from the Yunnan G. elata base were Armillaria gallica Marxm. & Romagn. The F2 and F3 strains isolated from the Jilin G. elata base were Armillaria cepistipes Velen. The growth rate comparison showed that the growth rates of M1, M2, and F2 were relatively fast and that of F3 was the slowest. The results showed that the extracellular enzyme activity and polysaccharides content of the four Armillaria spp. strains increased at the beginning and then decreased. The M1 and M2 strains of Armillaria gallica had relatively high enzyme activities and polysaccharides content. Based on the comprehensive analysis, the four strains were identified as Armillaria gallica and Armillaria cepistipes, respectively. Combining with the previous G. elata production results, it could be preliminarily confirmed that M1 and M2 strains are excellent strains for cultivating G. elata.

  Potential Saccharomyces cerevisiae Strains of Producing 2,3-butanediol: Screening Ding Hao, Liu Wenjuan, Sun Jian, Liu Lei, Ping Wenxiang, Ge Jingping 2020, 36 (24):  107-115.  DOI: 10.11924/j.issn.1000-6850.casb20190700383 Abstract + ( 201 )   HTML ( 5 )   PDF ( 2925KB )   ( 39 ) The aims are to obtain the potentially high-production 2,3-butanediol Saccharomyces cerevisiae, and study the 2,3-butanediol producing potential of different strains. The most promising Saccharomyces cerevisiae strain W141 for producing 2,3-butanediol was screened by morphological observation, product tolerance detection, key enzyme activity assay, acetoin yield and fermentation test. The results showed that the W141 grew rapidly, could withstand 13% (w/v) ethanol and 0.8% (w/v) acetic acid, respectively, and had the high ethanol production (0.593 g/g) and carbon source utilization rate (the glucose consumption rate was 100% after fermentation for 24 h). The enzyme activities of key enzymes α-ALS and BDH were higher, 0.046 U/mg and 0.040 U/mg, respectively. The key intermediate of the 2,3-butanediol pathway, acetoin, had a high content, which reached 0.246 g/L. The study indicates that Saccharomyces cerevisiae W141 has certain transformation space and application prospect in the fermentation industry.

  The Production of Bacteriocin Paracin1.7 by High-density Culture of Lactobacillus paracasei HD1.7: Condition Optimization Zhang Yan, Fang Baozhu, Ping Wenxiang, Ge Jingping 2020, 36 (24):  116-124.  DOI: 10.11924/j.issn.1000-6850.casb20190700440 Abstract + ( 601 )   HTML ( 3 )   PDF ( 1309KB )   ( 39 ) The fermentation broth of Lactobacillus paracasei HD1.7 found in the Chinese sauerkraut contains bacteriocin Paracin 1.7, it has the potential to become a new type of food preservative depending on its broad spectrum of inhibition. This study aims to increase the yield of bacteriocin Paracin1.7. Using L. paracasei HD1.7 as the starting strain, high-density culture of fermenter was used to optimize single-factor fermentation conditions and conduct orthogonal design to increase the yield of bacteriocin Paracin1.7. The results showed that during the fermentation process, the optimal inoculum was 3%, the optimal inoculum age was 18 h, the optimal liquid volume was 2 L/3.7 L, the optimal initial pH value was pH 5.5, and the optimal aeration was 0 L/min, the optimal rotational speed was 400 r/min, the optimal culture temperature was 35℃, and the optimal culture time was 24 h. Under the above optimized conditions, the titer of bacteriocin Paracin 1.7 in the fermentation broth was increased from 863.01±39.77 AU/mL before optimization to 978.46±7.16 AU/mL, which was 1.13 times of the original, and the density of the bacteria reached 1010 CFU/mL. By optimizing the fermentation conditions, the biomass and bacteriocin production of L. paracasei HD1.7 can be significantly improved, and the experimental basis for designing and improving high-density cultured cells is laid.

  The Interaction Between Magnaporthe oryzae and Rice: Research Progress Li Shan, Du Chunmei 2020, 36 (24):  125-131.  DOI: 10.11924/j.issn.1000-6850.casb20190800517 Abstract + ( 385 )   HTML ( 6 )   PDF ( 1228KB )   ( 115 ) To better prevent and control the occurrence of rice blast and provide the scientific basis for rice breeding and drug discovery, it is very necessary to explore the mechanism of interaction between Magnaporthe oryzae and rice. In this paper, the mechanism of M. oryzae infecting rice, the signal recognition and downstream response of rice to M. oryzae infection and the defense response mechanism induced by the fungi were summarized, and the expression and regulation of defense-related genes in rice and the molecular breeding strategies for improving rice disease resistance were analyzed. After M. oryzae infection, rice plant could resist the infection by self-defensive systemic response, such as thickening cell wall, expression of pathogenesis-related proteins and programmed cell death at the invasion site of M. oryzae, etc. It is pointed out that using genetic engineering means to induce plant immune response to resist the harm of M. oryzae has important practical significance, and it is also the most effective and cost-optimal method to control rice blast. Moreover, as a model system to study the pathogen-plant interaction, deeply understand the interaction mechanism between M. oryzae and rice can provide a scientific basis for the prevention and control of other important fungal diseases by inducing the expression of rice defense genes.

  Bacillus thuringiensis Sublethal Concentration: Effects on Population Reproduction of Callosobruchus chinensis (Linnaeus) Yang Jiale, Ma Xin, Cao Min, Yu Huiping, Yang Qian, Zhang Lixiang 2020, 36 (24):  132-135.  DOI: 10.11924/j.issn.1000-6850.casb20200100001 Abstract + ( 267 )   HTML ( 5 )   PDF ( 1203KB )   ( 30 ) In order to determine the effect of Bacillus thuringiensis on the population reproduction of Callosobruchus chinensis, a laboratory bioassay was conducted on the adults of Callosobruchus chinensis by macerating method. The results showed that the fatality rates of adults were 95.56%, 70.00%, 36.67%, 21.11%, 7.78%, respectively, when the doses of Bacillus thuringiensis were 80.0 IU/mg, 53.3 IU/mg, 32.0 IU/mg, 26.7 IU/mg, 20.0 IU/mg, respectively. Its virulence regression equation was y=0.38x+2.91. LC10, LC30 and LC50 significantly shortened the lifespan of the adults of Callosobruchus chinensis and inhibited the oviposition of female adults. After being treated by LC10, LC30 or LC50, the net reproduction rate, intrinsic growth rate and finite rate of increase were lower than that of the control, while the population doubling time was prolonged obviously. It indicates that Bacillus thuringiensis has a good insecticidal effect, and the sublethal dose has a significant inhibiting effect on the population development of Callosobruchus chinensis.

  Whitebacked Planthopper (Nilaparvata lugens Stål) in Xiang-Gui Corridor: Origin and Catastrophic Atmospheric Background Zou Lixia, Tang Guangtian 2020, 36 (24):  136-145.  DOI: 10.11924/j.issn.1000-6850.casb20190700360 Abstract + ( 309 )   HTML ( 2 )   PDF ( 2941KB )   ( 32 ) To clarify the influence of the early origin and atmospheric background of whitebacked planthopper (Nilaparvata lugens St?l) in Xiang-Gui corridor in the process of its northward immigration, the software HYSPLIT was applied to simulate the catastrophic immigration peak and backward trajectory of WBPH at the beginning occurrence stage, to analyze the main insect source and its catastrophic atmospheric background in terms of individuality and commonness, respectively. The results indicated that: (1) from 1991 to 2014, the beginning occurrence stage of immigration and the immigration peak for the first time of WBPH in Xiang-Gui corridor was 0.9 d/10 a and 1.6 d/10 a, respectively; (2) the southwestern path was the main path for the initial insect source of WBPH in Xiang-Gui corridor, and the southwest path of insect source accounted for 54%, 50%, 72% in Yongfu, Xing’an and Quanzhou station, respectively; (3) WBPH in the Indo-China Peninsula took off with a weak updraft, and the strong southwesterly flow at 850 hPa altitude with abundant water vapor conditions were conducive to its northward immigration; and precipitation was an important atmospheric dynamic mechanism for the landing of WBPH. The results provide a scientific basis for the off-site monitoring and scientific prevention and control of WBPH.

  Plant Growth Promoting Rhinoacteria: Effect of Growth Promotion and Disease Resistance on Garlic (Allium sativum L.) Lv Jun, Fu Chun, Xiao Ximeng, Yang Yaojun 2020, 36 (24):  146-153.  DOI: 10.11924/j.issn.1000-6850.casb20190800501 Abstract + ( 270 )   HTML ( 4 )   PDF ( 1442KB )   ( 38 ) To study the effect of different doses of plant growth promoting rhinoacteria (PGPR) on the growth promotion and disease resistance of garlic (Allium sativum L.) during the growth period, garlic seeds planted in pot were used as test materials, the germination rate of potted garlic seeds was calculated by counting method and the plant height was measured by conventional measurement method, nutrient content of planting soils was measured using soil temperature and humidity detector. Compared with the control group (CK), the ammonium nitrogen content of experimental group B (administered 4 g bacterial fertilizer) was increased by 117.60%, the effective potassium content was increased by 593.15%, and the available phosphorus content of the experimental group C (administrated 6 g bacterial fertilizer) was increased by 238.77%, the germination rate of garlic was increased by 15.17%, the plant height of seedlings was increased by 20%, and the chlorophyll was increased by 11.04% (P<0.05), indicating that PGPR had a promoting effect on garlic growth. The results of antagonistic test between garlic root rot pathogen and plant rhizosphere growth promoting bacteria showed that the harmful microbial index was decreased by 25% when bacterial fertilizer concentration was 10-2 under dark culture at 30℃, indicating that the antibacterial effect was significant. The results of this study indicate that PGPR has a significant effect on promoting the growth of garlic, and also has certain disease-resistant effect, which has potential economic value in agricultural development.

  Adding Lucid Ganoderma: Effect on Performance, Egg Quality, and NH3 and H2S Released from Feces of Laying Hens Li Shangmin, Jiang Yixiu, Fan Jianhua, Qu liang, Lu Jian, Dou Xinhong 2020, 36 (24):  154-158.  DOI: 10.11924/j.issn.1000-6850.casb20200300190 Abstract + ( 322 )   HTML ( 2 )   PDF ( 1132KB )   ( 48 ) This article aims to study the effect of lucid Ganoderma on the performance, egg quality, and NH3 and H2S released from feces of laying hens. Three hundred 35-week-old laying hens with good health condition and similar performance were divided into three groups randomly. There were five repetitions per group and twenty hens per repetition. The control group was fed with basic diet, and experimental groups were fed with lucid Ganoderma of a certain ratio as 0.3% and 0.6% into the basic diet. The experiment went on for 8 weeks. The results showed that: (1) the egg production rate in the 0.3% experimental group and the 0.6% experimental group was significantly higher than that in the control group (P<0.05), and the ratio of feed to egg was significantly lower than that in the control group (P<0.05), and there was no significant difference between the experimental groups (P>0.05); (2) the Haugh units in the 0.6% experimental group were significantly higher than those in the control group (P<0.05), but not significantly different from those in the 0.3% experimental group (P>0.05); the relative weight of eggshells in the 0.3% experimental group and the 0.6% experimental group were significantly higher than that in the control group (P<0.05), and the thickness of eggshells in the 0.6% experimental group was significantly higher than that in the control group and the 0.3% experimental group (P<0.05); (3) the release of NH3 from feces of the 0.3% experimental group and the 0.6% experimental group was significantly lower than that of the control group (P<0.05), which respectively decreased by 23.69% and 26.50%; the release of H2S from feces of the 0.6% experimental group was significantly lower than that of the control group (P<0.05) by 27.51%. Adding Ganoderma lucidum powder into the diet can significantly enhance the production performance of laying hens, reduce the ratio of feed to egg, improve the quality of eggs, and reduce the release of NH3 and H2S from feces.

  Flavonoids of Toona sinensis Leaves: Separating and Purifying with D-101 Macroporous Adsorptive Resin and the Antioxidant Activity Zou Hongfei, Shu Xiaoyan, Zhang Yueqin, Liu Yuan, Yang Wenyu, Zhao Guiying 2020, 36 (24):  159-164.  DOI: 10.11924/j.issn.1000-6850.casb20190800516 Abstract + ( 231 )   HTML ( 2 )   PDF ( 1222KB )   ( 25 ) The flavonoids in leaves of Toona sinensis were separated and purified with D-101 macroporous resin to get the utmost out of the leaves. The adsorptive capacity and stability of D-101 macroporous resin for flavonoids from T. sinensis leaves were studied with the adsorption rate, elution rate and purity of total flavonoids as indexes. At the same time, the antioxidant activity of T. sinensis flavonoids was evaluated by scavenging 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radicals. The results showed that the optimum sampling condition of D-101 macroporous resin was: the sample size of T. sinensis extract was 5 BV, the flavonoids concentration was 0.69 mg/mL, and the sampling flow rate was 3 BV/h. The optimum elution condition was: 70% ethanol was used as eluent, the dosage of eluent was 5 BV, and the flow rate was 3 BV/h. When the resin was used once, the purity of flavonoids of T. sinensis could be increased from 6.0% to 45.14%, and the resin was stable and could be reused for 6 times before regeneration. The flavonoids isolated and purified by macroporous resin had strong antioxidant activity, which was 1.33 times as much as ascorbic acid.