中国草莓主产区灰霉病菌的多样性研究

发布时间：2018-04-02 02:26

本文选题：草莓灰霉病菌　切入点：鉴定　出处：《中国农业大学》2015年博士论文

【摘要】：草莓灰霉病是草莓上的一种重要病害,危害严重、影响范围广泛,是导致草莓产量和质量降低的主要因素。本研究对引起草莓灰霉病的病原菌种类进行了鉴定,并对优势种灰葡萄孢的菌落特征、转座因子类型、交配型、致病力、对常用杀菌剂的抗性以及种群遗传多样性等方面进行了研究和分析,取得研究结果如下：1.从我国辽宁、河北、北京、安徽、四川和新疆6个省市自治区的草莓种植区采集分离到了255株灰霉病菌,综合形态学、Bc-hch基因的多位点酶切分析以及基于G3PDH, HSP60和RPB2的单基因和多基因系统发育分析的结果,表明我国草莓灰霉病的病原菌包括至少3个系统发育种：B. cinerea、B. sinoviticola和B. pelargoniio其中,B. cinerea是严格意义上的灰葡萄孢并且是绝对的优势种,而B. sinoviticola和B. pelargonii是首次在我国草莓寄主上发现,草莓是其在国内的新记录寄主。这是国内对来自寄主植物草莓上的灰葡萄孢种群组成的首次研究和发现。2.对B. cinerea和B. sinoviticola的代表菌株的菌落培养性状、菌丝生长速率、分生孢子大小、产孢量、致病力和对环酰菌胺的敏感性进行了测定和比较。结果显示,B. sinoviticola的菌株与B. cinerea相比,菌核体积小,数量多,分布密集；分生孢子长；对草莓叶片的致病力弱；两个种的菌株菌丝生长速率和产孢量差异不大,对环酰菌胺均表现敏感。3.对采自我国新疆、辽宁、河北、北京、安徽和四川6个草莓主产区的251株灰葡萄孢(B. cinerea)菌株的转座子类型、交配型、菌落及菌核形态、致病力以及对常见杀菌剂的抗性进行了分析。所有菌株的菌落形态有菌丝型、孢子型和菌核型,以菌核型为主。转座子类型存在transposa、vacuma、boty和flipper四种,transposa类型的菌株最多,占61.7%。存在MAT1-1和MAT1-2两种交配型,总体比例符合1：1。对草莓叶片的致病力分为弱致病力、中等致病力和强致病力,以中等致病力为主。根据菌株对多菌灵(Car)、腐霉利(Pro)和乙霉威(Die)的抗性和敏感性,共出现了8种表型,其中对多菌灵、腐霉利表现敏感但对乙霉威表现抗性的菌株最多,占28.3%。不同灰葡萄孢菌株表型特征差异明显,从而反映了我国草莓灰葡萄孢多样性丰富。4.采用SSR分子标记对灰葡萄孢的群体遗传多样性进行了研究。根据地理来源将所有菌株分为6个群体,基于SSR分析,共检测出165种多位点基因型,6个群体的平均基因多样性指数和平均基因型多样性指数分别为0.662和0.994,每个群体均存在丰富的基因型多样性及高水平的遗传多样性。PCoA分析将所有菌株分为2大遗传类群,其中河北的群体聚为一类,其余群体聚为一类。分子方差分析(AMOVA)发现群体内遗传变异为主,占总变异的97%。根据关联指数IA推测群体内以无性繁殖为主。群体间的遗传固定指数Rst在0.002-0.07之间,群体间存在较低到中等程度的遗传分化。
[Abstract]:Strawberry grey mold is an important disease on strawberry, which is harmful and has a wide range of effects. It is the main factor leading to the decrease of strawberry yield and quality. The colony characteristics, transposable factor type, mating type, pathogenicity, resistance to common fungicides and genetic diversity of population were studied and analyzed. The results are as follows: 1. 255 strains of Botrytis cinerea were isolated from strawberry growing areas in Hebei, Beijing, Anhui, Sichuan and Xinjiang provinces and autonomous regions. The results of multilocus digestion of Bc-hch gene and single gene and polygenic phylogenetic analysis based on G3PDH, HSP60 and RPB2 were summarized. The results showed that the pathogens of strawberry grey mold in China included at least three phylogenetic species: B. cinereaB. sinoviticola and B. pelargoniio. B. cinerea was a strictly dominant species of Grapevine, and B. sinoviticola and B. pelargonii were first found on strawberry hosts in China. Strawberry is a new record host in China. This is the first study on the population composition of Grapevine from the host plant strawberry in China. 2.The colony culture characters and mycelium growth rate of the representative strains of B. cinerea and B. sinoviticola were studied and discovered. The conidial size, sporulation, pathogenicity and sensitivity to cyclosporine were determined and compared. The results showed that the sclerotia of B. sinoviticola was smaller, more abundant and more dense than that of B. cinerea, and the conidia were long. The mycelium growth rate and sporulation quantity of the two strains were not different, and they were sensitive to cyanoamides. They were collected from Xinjiang, Liaoning, Hebei, Beijing, China. The transposon type, mating type, colony and sclerotia morphology, pathogenicity and resistance to common fungicides of 251 strains from 6 strawberry producing areas of Anhui and Sichuan were analyzed. The transpospore type and sclerotia type, the transposavacumaboty type and the flipper transposa type were the most common, accounting for 61.7%. There were two mating types, MAT1-1 and MAT1-2, and the overall ratio was 1: 1.The pathogenicity of strawberry leaves was divided into weak pathogenicity. According to the resistance and sensitivity of the strains to carbendazim Caranum, Propion and Diedil), there were 8 phenotypes, including carbendazim, carbendazim, carbendazim, carbendazim. The phenotypic characteristics of different Grapevine strains were significantly different from those of Pythium spp, but resistant to ethidium ethylpyrrolidis was the most, accounting for 28.3%. The results showed that the diversity of Chinese strawberry grapevine spores was rich. 4. The genetic diversity of the species was studied by SSR molecular marker. All the strains were divided into 6 populations according to their geographical sources, and the results were based on SSR analysis. A total of 165 multiloci genotypes were detected. The average genetic diversity index and average genotype diversity index of 6 populations were 0.662 and 0.994, respectively. Each population had abundant genotypic diversity and high genetic diversity. PCoA. All the strains were divided into two major genetic groups. Among them, the population of Hebei was clustered into one group, and the other populations were clustered into one class. The analysis of molecular variance (AMOVA) found that genetic variation was dominant in the population. According to the correlation index IA, asexual reproduction was the main factor in the population. The genetic fixed index (Rst) of the populations was between 0.002-0.07, and there was low to moderate genetic differentiation among the populations.
【学位授予单位】：中国农业大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：S436.68

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