Current issue

• 2021 Vol.37 No.14 Published:15 May 2021

  Weak Gluten Wheat ‘Ningmai 13’: Effect of Increasing Density and Reducing Nitrogen on Yield and Quality Xu Jun, Yao Yuan, Qian Chencheng, Ding Jinfeng, Li Chunyan, Zhu Xinkai, Guo Wenshan, Zhu Min 2021, 37 (14):  1-8.  DOI: 10.11924/j.issn.1000-6850.casb2020-0573 Abstract + ( 346 )   HTML ( 5 )   PDF ( 1278KB )   ( 160 ) The aims are to achieve the high quality and stable production of weak gluten wheat and solve the problem of its poor quality stability. ‘Ningmai 13’ was used as the material, and variance analysis was adopted to investigate the effects of increasing density and reducing nitrogen on the yield, the population quality index and grain quality of weak-gluten wheat. The results showed that, the LAI and dry matter accumulation both indicated a trend of increasing first and then decreasing with the increase of density at the nitrogen application level of 240 kg/hm2. The density exceeding 240×104/hm2 would lead to the decrease of LAI and dry matter accumulation. Under the density of 240×104/hm2, the nitrogen content exceeding 240 kg/hm2 could cause the decrease of wheat leaf area index, SPAD value, dry matter accumulation after flowering and yield. Appropriately increasing density and reducing nitrogen was conducive to improving the quality and stable yield of weak gluten wheat, while excessively increasing density and reducing nitrogen would result in yield decreasing and unstable quality. Based on these results, the recommendation to achieve high yield and better quality for ‘Ningmai 13’ is: the planting density of 240×104/hm2, the nitrogen application rate of 180 kg/hm2 and the nitrogen application mode of 7:1:2:0.

  Quality Characters of Wheat Varieties in Spring Series: Analysis and Evaluation Lei Jianfeng, Su Lili, He Yunjian, Zhou Guiling, Dai Peihong 2021, 37 (14):  9-14.  DOI: 10.11924/j.issn.1000-6850.casb2020-0380 Abstract + ( 462 )   HTML ( 12 )   PDF ( 1277KB )   ( 52 ) The objectives are to explore the quality characteristics of different spring wheat varieties in Xinjiang, establish a reliable quality evaluation system for wheat, and lay a foundation for the promotion, breeding and large-scale quality evaluation of Xinjiang spring wheat varieties with outstanding comprehensive performance. Nine accessions of spring wheat lines were used as experimental materials, fourteen quality-related indexes were determined, and the wheat qualities were analyzed and comprehensively evaluated by correlation analysis, principal component analysis and cluster analysis. The results showed that there was a large or small correlation between the fourteen single indexes, which led to the partially overlapped information. Fourteen single indexes were further classified into five independent comprehensive indexes by principal component analysis. The cumulative variance contribution rate of the five principal component was 94.46%, which covered most of information carried by the original measurement indexes; According to membership function analysis combined with weight coefficient, the comprehensive evaluation value (D value) of different wheat varieties’ quality were obtained. Finally, the nine wheat varieties were divided into three types according to their quality by cluster analysis. Among them, there was one variety with general quality, four varieties with good quality and four varieties with high quality. The comprehensive quality performance of ‘Xinchun 37’, ‘Xinchun 41’ and ‘Xinchun 38’ is relatively outstanding, which can provide reference for selection and breeding of high-quality spring wheat varieties in Xinjiang.

  Seed Treatment: Effects on Emergence and Physiological Traits of Early-sowing Maize Hou Wen, Du Zhuo, Zhang Fengyun, Wu Ziwen, Wang Li, Lu Yuncai 2021, 37 (14):  15-20.  DOI: 10.11924/j.issn.1000-6850.casb2020-0514 Abstract + ( 319 )   HTML ( 7 )   PDF ( 1349KB )   ( 195 ) To provide new technologies for the resistance to low temperature damage of maize, the hybrid seeds of maize were used as materials, 16 groups of seed treatment were designed, including exogenous plant growth materials, compound solutions, ultrasonic wave, seed coating agents and so on. The low temperature stress was simulated by early sowing in the field. The effects of early sowing on the emergence rate, SPAD value, soluble sugar, soluble protein and peroxidase activity were studied. The results showed that the emergence rate of early-sowing maize significantly increased with seed-coating agent. The SPAD value of plant chlorophyll also significantly increased. For T8 coating treatment, the soluble sugar content significantly increased by 34.24%, compared with CK. For T5, T7, T8 and T10 coating treatment, the soluble protein content increased by 8.60%, 21.72%, 9.70% and 19.16%, respectively. For T1, T2, T3, T10, T14 and T15 treatment, the peroxidase activity increased compared with CK. All treatment groups with seed coating agents had significant effects on alleviating low temperature damage. Totally, the integrated strategies of seed priming, ultrasonic treatment and seed coating technology can improve the cold resistance of early sowing maize.

  Calcium Nitrate and Magnesium Sulfate Combination: Effect on Sugarbeet Seed Germination Liu Zhaoyang, Wang Ronghua, Wang Weicheng, Liu Xiaoyue, Liu Na, Liu Xiaohan, Liu Dali, Wu Zedong, Wang Maoqian 2021, 37 (14):  21-26.  DOI: 10.11924/j.issn.1000-6850.casb2020-0529 Abstract + ( 523 )   HTML ( 5 )   PDF ( 1164KB )   ( 57 ) To determine the priming effect of different concentrations of calcium nitrate and magnesium sulfate combination on sugarbeet seeds, and provide a basis for the selection of sugarbeet seed coating agent materials, the seeds of TD802 sugarbeet were used as experimental materials, twelve initiator combinations were set up, and the germination potential, germination rate, germination index and vigor index were determined by soaking and drying the beet seeds. The results showed that the indexes of treatment 1-3 were higher than those of the control, the germination potential (88.33%) and germination index (35.42) of treatment 2 were the highest, and the germination rate (91.33%) and vigor index (206.09) of treatment 3 were the highest. The indexes of treatment 4-6 were higher than those of the control, among which, treatment 6 (germination potential 93.00%, germination rate 91.33%, germination index 47.53, and vigor index 166.88) had the best effect. The indexes of treatment 7-9 were higher than those of the control, among which, treatment 7 had higher germination potential (88%), germination rate (91.33%) and germination index (36.33), treatment 9 had higher vitality index (211.23). The indexes of treatment 10-12 were generally lower than those of control. In general, the effects of different concentrations of calcium nitrate and magnesium sulfate combination on sugarbeet seed priming are different, treatment 1-9 all promote sugarbeet seed priming, among which, treatment 6 has the best priming effect, while treatment 10-12 inhibit sugarbeet seed priming.

  BvM14-RIN4 Gene of Sugar Beet M14 Line: Cloning and Response to Salt Stress Jia Huixu, Li Haiying, Duanmu Huizi 2021, 37 (14):  27-33.  DOI: 10.11924/j.issn.1000-6850.casb2020-0848 Abstract + ( 306 )   HTML ( 5 )   PDF ( 1543KB )   ( 40 ) To study the salt-resistant function of RIN4 gene in sugar beet monosomic additional line M14 line, sugar beet M14 line was used as experimental material, the full-length cDNA sequence of the BvM14-RIN4 gene was obtained by PCR, and the BvM14-RIN4 gene was analyzed by bioinformatics and its tissue specificity and response to salt stress were explored. The results showed that the ORF length of BvM14-RIN4 gene was 264 bp which encoded 87 amino acids, the molecular weight of the protein was 9.67 kDa, the theoretical pI was 9.64, and the protein was preliminarily identified as a hydrophilic protein. The secondary structure of BvM14-RIN4 protein was mainly composed of extension chain and random curl; the tertiary structure of BvM14-RIN4 protein predicted the conserved domain and hydrophobic region of the protein; the phylogenetic tree showed that BvM14-RIN4 protein was closely related to RIN4 protein of Spinacia oleracea L. and Chenopodium quinoa L.. The results of quantitative RT-PCR showed that the expression level of BvM14-RIN4 gene in roots leaves was 2.26 times that of leaves, which indicated that it had tissue specificity; the expression of BvM14-RIN4 gene was up-regulated in roots under 200 mmol/L NaCl, which indicated that it was involved the response of sugar beet M14 line to salt stress. This study is of certain significance in mining high quality genes of sugar beet M14 line and carrying out genetic improvement of sugar beet, the results could provide important references for studying the function of BvM14-RIN4 gene.

  MYB44 Gene from Solanum Lycopersicum: Bioinformatics Analysis and Subcellular Localization Li Ying, Wang Yingying, Su Xu, Gu Jiantian 2021, 37 (14):  34-40.  DOI: 10.11924/j.issn.1000-6850.casb2020-0807 Abstract + ( 471 )   HTML ( 8 )   PDF ( 1483KB )   ( 47 ) The aims are to analyze the biological function of SlMYB44 gene and provide a scientific basis for exploring its mechanism of resisting chilling injury. In this study, the Russian cultivated tomato bolgogragsky was used as the material, and according to the sequencing results of transcriptome, the differentially expressed gene SlMYB44 was selected as the research object. The conservative functional domain, hydrophilicity or hydrophobicity, signal peptide and promoter cis-acting elements of tomato SlMYB44 gene were analyzed by using various bioinformatics databases. The expression vector pMDC43-MYB44 was constructed for subcellular localization analysis. SlMYB44 gene encoded 372 amino acids with a total length of 1551 bp. SlMYB44 protein had no potential signal peptide site and membrane spaning domain, which belonged to labile protein and hydrophilic protein. The analysis of cis-acting elements of SlMYB44 gene promoter showed that most of them were related to adversity stress and hormone response. Subcellular localization analysis demonstrated that the expression product of SlMYB44 gene was localized in the cell nucleus. In conclusion, the SlMYB44 gene responds to chilling injury, it is further speculated that it might affect the tomato chilling mechanism.

  Anthocyanin Biosynthesis and Regulate Mechanisms in Plants: A Review Liu Kaiyuan, Wang Maoliang, Xin Haibo, Zhang Hua, Cong Richen, Huang Dazhuang 2021, 37 (14):  41-51.  DOI: 10.11924/j.issn.1000-6850.casb2020-0390 Abstract + ( 1224 )   HTML ( 24 )   PDF ( 2103KB )   ( 4831 ) To elaborate the mechanism of anthocyanin biosynthesis in plants and understand the various factors affecting anthocyanin synthesis as well as their interaction, we summarize the internal and external regulatory factors and concluded the environmental factors such as light, temperature, carbohydrate and hormone. Around the anthocyanin biosynthesis pathway, the structural genes in the pathway and its upstream transcription factors are described and analyzed. This study concludes that in plants, all kinds of external and internal factors regulate structural genes through the main transcription factors, affect the biosynthesis and accumulation of anthocyanins in plants, and maintain the dynamic balance of anthocyanins in plants. This regulation includes both positive and negative regulation. In summary, metabolic pathway of anthocyanins is gradually improved, at the same time, novel structural genes and transcription factors will be evaluated and used in genetic engineering improving the characteristics of ornamental plants.

  Different Rooting Powder Concentrations: Effects on Budding and Rooting of Cutting Segments in 5 Woody Plants Jiang Yudong, Xiong Youqing, Zhang Junmin 2021, 37 (14):  52-58.  DOI: 10.11924/j.issn.1000-6850.casb20191100875 Abstract + ( 613 )   HTML ( 9 )   PDF ( 4266KB )   ( 45 ) In recent years, 5 woody plants with elite ornamental traits and broad environmental adaptability, namely Caryopteris mongholica Bunge, Caryopteris×clandonensis. ‘Worcester Gold’, Hippophae rhamnoides Linn., Elaeagnus angustifolia Linn. and Symphoricarpos albus, are introduced into the landscaping of Beijing. To expand their plantation, we investigated the mass propagation by cutting methods, and studied the effects of different concentrations of rooting powder on budding and rooting rate of their cuttings. The results show that certain concentrations of rooting powder could promote the budding rate of Caryopteris mongholica Bunge, Caryopteris×clandonensis. ‘Worcester Gold’ and Hippophae rhamnoides Linn., enhance the rooting rate of Hippophae rhamnoides Linn., Elaeagnus angustifolia Linn. and Symphoricarpos albus, and improve the number of roots of Caryopteris mongholica Bunge, Caryopteris×clandonensis. ‘Worcester Gold’, Hippophae rhamnoides Linn. and Symphoricarpos albus. The regenerated root length of cuttings of these 5 woody plants is significantly improved by rooting powder of medium to low concentrations. Furthermore, rooting powder treatments could also promote the survival rate of cuttings in pot in Elaeagnus angustifolia Linn.. In conclusion, the treatment with 0.15-0.5 g/L rooting powder could significantly increase the budding, rooting, root length or survival rate of cuttings of the 5 woody plants, thus facilitate the mass propagation of these woody plants by cuttings.

  Agronomic Character Analysis of Stropharia rugoso-annulata Cultivated in Solar Greenhouse with Different Formulas and Preparation Techniques Yang Qizhi, Zhao Qingqing, Chen Qingjun, Zhang Guoqing, Liu Guiping 2021, 37 (14):  59-65.  DOI: 10.11924/j.issn.1000-6850.casb2020-0639 Abstract + ( 375 )   HTML ( 6 )   PDF ( 1396KB )   ( 56 ) In this research, we studied the most suitable formula and preparation techniques of Stropharia rugoso-annulata cultivation in the sunlight greenhouse by using peach sawdust and corn agricultural waste from Pinggu in Beijing. This article set up 3 preparation and 6 formulas, and comprehensively compared the agronomic traits such as physical and chemical traits, fruiting traits, average yield and biological efficiency. We find that raw materials are significantly superior to fermentation materials in agronomic characters and yield. Fermentation material + short time high temperature is slightly better than fermentation material in yield and agronomic characters. In raw materials, the maximum yield of S-1 (peach sawdust and corn cob) formula is 11.97 kg/m2, its biological efficiency is 99.75%, and its fruit body traits are excellent. The formula of S-2 (peach sawdust and corn straw) is the best in fruiting body characters, such as mushroom shape index and weight of single mushroom, the time from sowing to fruiting is short, and the yield and biological efficiency are also high. The multi-material mixing of S-3 (peach sawdust, corn stalk and corn cob) is conducive to the formation of early yield. The raw material cultivation techniques of these three formulas are all suitable for the cultivation of Stropharia rugoso-annulata in Beijing. This paper could provide technical support for popularizing and cultivating Stropharia rugoso-annulata and using peach sawdust resources in Pinggu of Beijing.

  Regional Distribution Characteristics and Influencing Factors of Soil Cation Exchange Capacity in Jiangxi Kang Ting, Zhou Chunhuo, Wei Zongqiang, Miao Yulin, Lu Zhihong 2021, 37 (14):  66-71.  DOI: 10.11924/j.issn.1000-6850.casb2020-0486 Abstract + ( 404 )   HTML ( 6 )   PDF ( 1448KB )   ( 106 ) To improve soil fertility in Jiangxi Province, the regional distribution characteristics of soil cation exchange capacity and the influencing factors were studied. The ammonium acetate exchange method was used to determine the cation exchange capacity of 367 soil samples in surface soil and analyzed their regional distribution characteristics. The results showed that: (1) the content of soil cation exchange capacity in dry soil and paddy soil had a large variation, and the proportion of soil CEC content less than 10.5 cmol (+)/kg was as high as 82.02%, the paddy soil with low capability of conserving fertilizer was 2.46% higher than that of dry soil; (2) according to the proportion of soil with medium capability of conserving fertilizer, the distribution of CEC content in dry soil and paddy soil in Jiangxi was highly consistent, with the order of west Jiangxi >central Jiangxi > north Jiangxi > northeast Jiangxi > south Jiangxi; (3) the soil cation exchange capacity in Jiangxi was mainly affected by organic matter and total N (P<0.05), followed by soil pH, available N, available K, total P and total K, while available P had the least influence. In Jiangxi Province, the capability of conserving fertilizer of cultivated land is weak, and the capability of conserving fertilizer of dry soil is slightly stronger than that of paddy soil.

  Regional Soil and Water Conservation and Soil Erosion: Prediction Analysis and Example Study Wang Meiyu, Dai Changlei, Zhang Kaiwen, Han Xinyu 2021, 37 (14):  72-77.  DOI: 10.11924/j.issn.1000-6850.casb2021-0102 Abstract + ( 469 )   HTML ( 7 )   PDF ( 1699KB )   ( 54 ) In the context that the Ministry of Water Resources has proposed the implementation of regional soil and water conservation assessment for various types of development zones, we analyzed the methods and technical points of soil erosion volume prediction. Taking Qing’an Development Zone as an example, the analysis of soil erosion prediction and soil balance estimation of China’s northeastern black soil area could provide reference for soil erosion calculation and soil and water conservation assessment in similar areas. Through the calculation and analysis, two conclusions are obtained: (1) considering the most unfavorable conditions, the largest amount of new soil loss is from industrial land in the prediction area; (2) for the planning and construction areas and the areas under construction, the plan of soil and water conservation for completed typical project could be used for analogous calculation of the regional soil excavation and filling methods.

  Multi-component Content Analysis and Water Quality Evaluation of Groundwater in Anxin Jia Liangliang, Tian Xiaohua, Liu Huajie 2021, 37 (14):  78-83.  DOI: 10.11924/j.issn.1000-6850.casb2021-0134 Abstract + ( 409 )   HTML ( 8 )   PDF ( 1539KB )   ( 31 ) To find out the chemical characteristics of groundwater and the present situation of water quality in Anxin, 45 groups of groundwater samples were selected and determined by the method of instrument analysis and volumetric method. The main ionic characteristics of groundwater in Anxin were analyzed by using comprehensive descriptive mathematical statistics and ternary phase diagrams. Groundwater quality was evaluated by comprehensive evaluation method. The results show that: (1) in this area the groundwater is slightly alkaline, hydro-chemical type is mainly HCO3-Na; (2) pH and metasilicate acid have the lowest spatial variation (CV<30%); the spatial variability of potassium and nitrate are the highest (CV>100%); the spatial variation of other indexes are moderate (CV: 30%-100%); (3) the main indexes that affecting the quality of groundwater environment are TDS, SO42-, F- and total hardness; (4) the results of water quality evaluation show that the groundwater quality is well, mostly are III water. The results are important for understanding the present situation of groundwater quality in Anxin.

  Screening of Glyphosate Degrading Bacteria in Wastewater Treatment Plant and Study on Their Degradation Characteristics Xu Bin, Han Ping, Xue Yufen 2021, 37 (14):  84-89.  DOI: 10.11924/j.issn.1000-6850.casb20200300287 Abstract + ( 419 )   HTML ( 6 )   PDF ( 1262KB )   ( 32 ) To solve the problem of glyphosate pollution of water body in agricultural production, this paper reported a strain with strong degradation ability of glyphosate, Bacillus megaterium, which was isolated from sewage plant activated sludge, and studied its growth curve and glyphosate degradation ability. Results showed that the glyphosate degradation rate within 48 h was up to 54.67% by Bacillus megaterium grown in 500 mmol/L glyphosate medium. Bacillus megaterium could grow in a broad range of pH with the most suitable growth pH value of 6.0. In heavy metal toxicity test, Cu2+ concentration of 50 mg/kg in the environment was disadvantageous to the degradation of glyphosate by Bacillus megaterium, and the degradation rate was 65.6%, while the Cu2+ concentration of 250mg/kg could reduce the degradation rate to 37.9%; Cd2+ concentration of 0.25 mg/kg and 2.5 mg/kg could inhibit the degradation rate of Bacillus megaterium to 50.4% and 28.8%, respectively.

  Preparation and Environmental Protection Performance of Gelatin/PVA Coating Materials of Fertilizers Liu Ying, Wei Min, Yang Pinghua, Geng Dandan 2021, 37 (14):  90-96.  DOI: 10.11924/j.issn.1000-6850.casb2021-0095 Abstract + ( 431 )   HTML ( 8 )   PDF ( 1493KB )   ( 56 ) Environmentally friendly resin has been used as coating materials in manufacturing controlled/slow release fertilizers to prevent the potential damage of resin to soil. The coating materials with various mass ration of gelatin/PVA were obtained by solution blending. The chemical structures of the materials were investigated by FTIR and SEM, the tensile strength, breaking extension and nutrient release rate were measured. Moreover, the biodegradation behaviors of the materials under controlled composting conditions and the acute oral toxicity in mice were studied. The results showed that an optimal compatibility could be achieved when the mass ratio of PVA to gelatin was 4 to 1. The coating materials had good mechanical properties, biodegradability and sustained release properties. The materials were actually non-toxic to mice and had relatively good safety. In general, gelatin/PVA coating materials of fertilizers have good environmental protection performance and application prospect.

  Land Use and Spatial and Temporal Change of Normalized Difference Vegetation Index (NDVI) in Shenfu Mining Area and Their Driving Factors Analysis Xia Zhengqing, Xie Yanling, Wang Tao 2021, 37 (14):  97-105.  DOI: 10.11924/j.issn.1000-6850.casb2020-0196 Abstract + ( 317 )   HTML ( 6 )   PDF ( 1899KB )   ( 37 ) The aim is to study land use changes caused by human activities in mining areas and their impact on vegetation index changes. Taking Shenfu mining area in Shaanxi Province as the research scope, combing with the comprehensive land use and MODIS NDVI data, the temporal and spatial variation process and driving factors of land use and NDVI were analyzed with linear trend method and correlation coefficients. The results showed that the characteristics of land use change from 2000 to 2010 were the conversion of large areas of farmland to grassland and rapid increase of construction land. From 2000 to 2015, NDVI showed a linear increase trend and the linear increase rate was 0.105/10a (P<0.001). The NDVI significantly increased area accounted for 95.95% of the total area, while only the river valley and the area near the town showed a decreasing trend. The decline area of farmland and the expansion area of construction land led to the decrease of NDVI, but the increase area in grassland and woodland resulted in the increase of NDVI. NDVI from 2000 to 2015 was mainly negatively correlated with temperature, and was significantly and positively correlated with precipitation, accounting for 97.79% of the total area. The negative correlation was concentrated in the vicinity of towns and river valleys by plaques and lines. The study indicates that urban expansion caused by social and economic development and the grain for green project implementation are the main driving factors for land use change in Shenfu mining area, and climate change, especially the increase of precipitation and the increase of grassland and forest land area, has promoted the increase of NDVI.

  The Effects of Extreme Weather Events on Crops in Guangxi from 1978 to 2017 Wang Aofeng, Chen Shiheng, Tang Xiangling 2021, 37 (14):  106-115.  DOI: 10.11924/j.issn.1000-6850.casb2020-0461 Abstract + ( 368 )   HTML ( 6 )   PDF ( 2387KB )   ( 40 ) Based on the disaster theory, this study is designed to research the effects of four extreme weather events (drought, flood, wind & hail and low temperature) on crops in Guangxi from 1978 to 2017 through the trend analysis method of mathematical statistics, so as to reduce the loss of crop yield and economy caused by extreme weather events. In this study, the response frequency of climate factors of extreme weather events was used to approximate the probability of extreme weather occurrence in a certain region. Then, through the damage assessment of the extreme weather events from 1978 to 2017, the temporal and spatial analysis of drought, flood, wind & hail and low temperature disasters in Guangxi was carried out to reveal their temporal and spatial variation trend. The results showed that: (1) in terms of the damage degree to crops, the four disasters were in the order of drought > floods > low temperature > wind & hail; (2) the affected areas and disaster areas of crops caused by drought in Guangxi showed a downward trend, and the severely damaged areas gradually shifted from the central and western regions to the southwest and northeast regions; (3) the affected areas and disaster areas of crops caused by floods showed an increasing trend, and the severely damaged areas gradually shifted from the south to the central and western regions; (4) the damage areas and disaster areas of crops caused by wind & hail disaster showed a downward trend, and the damage areas gradually shifted from the north and south to the central and more south regions; (5) the affected areas and disaster areas of crops caused by low temperature disaster showed an increasing trend, and the damage areas were mainly in the north of Guangxi.

  Climate Change Characteristics of Soil Moisture in Forage Growing Season in Hezuo of Gannan Plateau Ning Heping, Liu li, Luan Zhenbin, Luo Wangjun 2021, 37 (14):  116-122.  DOI: 10.11924/j.issn.1000-6850.casb2020-0584 Abstract + ( 360 )   HTML ( 8 )   PDF ( 1341KB )   ( 70 ) Based on the soil moisture data which were observed in forage growing season (April to September) in Hezuo of Gannan, Gansu Province from 1994-2013, we analyzed the depth variation characteristics of soil moisture in the area. The results show that the soil moisture in Hezuo exhibits an increasing trend during forage growing season, especially in the surface layer of 10 cm. And the trend weakens as the depth increases. In terms of seasonal change, the soil moisture of the whole layers is low in mid-June and mid-August, and high in mid-July, late July and September. The mutation detection analysis indicates that the moisture of both 20cm and 40cm soil layer in Hezuo present a jump increase. Soil moisture during summer is positively correlated with summer air temperature and precipitation in Hezuo, and the correlation with precipitation is more significant, showing a good consistency in the variation trend. The biomass of forage in each month in the growing season is closely related to previous soil moisture, which means that the soil moisture has positive contribution to forage yield.

  The Characteristics of Temporal and Spatial Changes of Land Use at County Level Based on Geographical Atlas—Take Youyang Tujia and Miao Autonomous County as an Example Liu Yueyang, Du Chong, Gong Wenfeng, Liu Tiedong, Nie Tangzhe, Liu Tao, Cao Kaihua, Xu Chenglong 2021, 37 (14):  123-135.  DOI: 10.11924/j.issn.1000-6850.casb2020-0241 Abstract + ( 343 )   HTML ( 9 )   PDF ( 3670KB )   ( 37 ) The study aims to explore the characteristics of land use evolution and geographic ecological process in Youyang County from 2000 to 2015, and provide a scientific basis for the sustainable use of regional land resources. We used map theory informatics to study the spatial distribution characteristics and temporal and spatial evolution of regional land use. The results showed that different land types in the study areas had different development trends during the 15 years. The land use structure was mainly forestland and grassland with the area ratio of 86.79%, 88.54%, 86.13%and 85.86%, respectively, and the forestland had a dominant position. There are certain differences in the types and areas of the main graph units of the three sequential units. In the map of land use rise and fall, forestland had the largest rise area, accounting for 38.67% of newly increased area, and grassland had the largest fall area, accounting for 38.03% of the shrink area. The research could provide certain scientific support for the sustainable development of land use and ecological construction in Youyang County in the future.

  Antagonistic Bacteria of Phytophthora infestans in Potato: A Review Gao Mengying, Fu Haiyan, Sun Cong, Wang Yanbo, Liu Chunguang, Ma Yukun, Yang Fengshan 2021, 37 (14):  136-140.  DOI: 10.11924/j.issn.1000-6850.casb2020-0546 Abstract + ( 323 )   HTML ( 6 )   PDF ( 1034KB )   ( 96 ) The aim is to solve the problem of death caused by Phytophthora infestans and low yield per unit in potato planting. In this paper, we started with antagonistic bacteria, summarized and analyzed the inhibitory effects of Bacillus, Pseudomonas and myxobacteria on Phytophthora infestans in potato. At the same time, based on the previous studies, in the application of antagonistic bacteria, we used the new many-to-one plate confrontation sieve model to simulate the antagonistic action of antagonistic bacteria, in order to get stable antagonistic bacteria. We pointed out that the feasibility of practical application of antagonistic bacteria should be studied from colonization ability and influence of rhizospheric microorganisms. In addition, we proposed that the future exploration of antagonistic antibacterial inhibition of potato Phytophthora infestans should go from the phenotypic level to the molecular level, in order to successfully find the answer from the source to inhibit Phytophthora infestans in potato.

  PGPR: The Biological Control Mechanism and Potential as Biological Control Agent Ji Yanfei, Dong Xinxin, Tian Ye, Zhang Jie, Yang Hongyi 2021, 37 (14):  141-149.  DOI: 10.11924/j.issn.1000-6850.casb2020-0295 Abstract + ( 728 )   HTML ( 24 )   PDF ( 1750KB )   ( 164 ) Plant growth promoting rhizobacteria (PGPR) is a type of soil bacteria that can enhance plant growth and disease resisting ability. Besides improving nutrients’ absorption, plant substance accumulation, and promoting various growth parameters of physiological and biochemical indexes of plants, PGPR can also protect plants from diseases in various ways. The biological control activity of PGPR relies on the colonization of plant rhizosphere, which is realized by the secretion of specific biological control active substances and the inducing of systemic resistance of plants. The rhizosphere colonization of PGPR can inhibit pathogens, which is crucial to the control of some plant diseases that are difficult to be realized by chemical agents. This paper discusses the biological control mechanism of PGPR, and the possibility of using PGPR as biological control agent for plant diseases, which might provide new views for the ecological agriculture development.

  Synergistic Antifungal Activity of Natural Phenolic Compounds and Two Chemical Fungicides Li Jiajun, Tao Lihong, Ye Min, Wang Kaibo, Wu Wenwei, He Chengxing, Fan Liming, Su Fawu 2021, 37 (14):  150-157.  DOI: 10.11924/j.issn.1000-6850.casb2020-0656 Abstract + ( 453 )   HTML ( 3 )   PDF ( 1266KB )   ( 166 ) In order to explore the synergistic effect of the mixtures of natural phenolic compounds (thymol and honokiol) with synthetic fungicides (chlorothalonil and boscalid) and screen out the novel fungicide mixtures which could control gray mold, in this study, thymol and honokiol were mixed with chlorothalonil and boscalid in different proportions, respectively, and the antifungal activity of the mixtures against Botrytis cinerea was determined by mycelium growth rate method. The Bliss’s method, Mansour’s method and Sun’s method were combined to optimized screening program, and the combined toxicity of the fungicide mixtures was evaluated. The results showed that the combination of Bliss’s method, Mansour’s method and Sun’s method could effectively reduce the screening workload and achieve high accuracy. The mixtures of thymol and chlorothalonil in mass ratios of 5:1, 2:3, 1:5, 1:10, and the mixtures of honokiol and chlorothalonil in mass ratios of 10:1, 5:1, 3:2, 2:3 and 1:10 showed a good synergistic effect. Among the mixtures of honokiol and chlorothalonil, the mass ratio of 10:1 showed the highest synergistic effect, with CTC value of 309.15. The mixture of honokiol and chlorothalonil in the mass ratio of 1:10 showed the highest antifungal activity, with EC50 value of 0.29 mg/L against B. cinerea, which was higher than that of chlorothalonil. Therefore, the combined use of the qualitative analysis methods and quantitative analysis methods is a proper scheme to screen the fungicide mixtures. The mixtures of natural phenolic compounds (thymol and honokiol) and chlorothalonil at reasonable ratios has the potential to control gray mold.

  Prothioconazole and Imazalil Mixtures: Co-toxicity and Field Control Efficacy on Fungus of Rice Bakanae Disease Chen Hongzhou, Yang Zhixiang, Zhang Xinjian, Yang Hongfu, Xu Chao, Miao Kang, Chen Yuan, Yao Kebing 2021, 37 (14):  158-164.  DOI: 10.11924/j.issn.1000-6850.casb2021-0008 Abstract + ( 605 )   HTML ( 3 )   PDF ( 1319KB )   ( 34 ) To explore the co-toxicity and field control efficacy of the mixtures of prothioconazole and imazalil on rice bakanae disease, and develop a new reagent for controlling rice bakanae disease, Fusarium fujikuroi was used as material in this study. The toxicity of prothioconazole, imazalil and their seven mixtures on F. fujikuroi was detected by using mycelium growth rate method, and field control tests with the optimum formulation were conducted. The results showed that the synergistic coefficient was 1.9778 when the mixture ratio of prothioconazole and imazalil was 1:1, the synergistic effect was the most significant. In the field control efficacy test, the control efficacy of 500 dilution of 5% prothioconazole·imazalil WS at seedling stage, tillering stage and heading stage were 91.08%, 92.85%, and 89.52%, respectively, which were higher than that of 1000 dilution of 4.23% metalaxyl·ipconazole ME or 1000 dilution of 12% fluazinam·tebuconazole·cartap WS, and all treatments were safe to the seed germination and seedling formation of rice. In conclusion, 5% prothioconazole·imazalil WS could provide excellent control efficacy on rice bakanae disease and is safe for rice growth, which can be developed as a rice bakanae disease control agent.