新疆不同地区葡萄霜霉病菌致病性分化及遗传多样性的分析

为了解新疆不同地区葡萄霜霉病菌Plasmopara viticola的遗传特征,分别采用叶盘接菌法及SSR分子标记技术对采自新疆吐鲁番、阿克苏、石河子等11个不同产区的葡萄霜霉病菌菌株的致病性进行测定,并分析各菌株的遗传多样性。结果显示,来自新疆不同地区的菌株种内存在着致病性分化现象,依据其在鉴别寄主上致病性的差异,将供试菌株划分为强、中、弱3类,其中强致病性菌株为优势菌株,且种间致病性分化与菌株的地理来源无关;SSR标记结果表明,供试菌株之间存在遗传变异现象,并且菌株之间亲缘关系都较近,在相似系数为0.93时,48株菌株聚为4大类,且遗传分化与地理分布具有一定的相关性。研究表明新疆不同地区的葡萄霜霉病菌菌株之间存在致病性分化与遗传变异现象。

Genetic diversity and pathogenicity differentiation of grapevine downy mildew causal agent Plasmopara viticola in different regions of Xinjiang

In order to find out the genetic characteristics of grape downy mildew pathogen Plasmopara viticola from different regions in Xinjiang, pathogenicity differentiation of strains was studied by leaf disc inoculation method, and genetic variation among different stains was analyzed with SSR molecular markers. The results showed that pathogenic differentiation was found among the strains from different regions of Xinjiang. According to its different pathogenicity in the differential host, the strains were divided into strong, medium and weak pathogenic strains. The strong pathogenic strains were dominant strains, and interspecific pathogenic differentiation had no correlation with the geographical source. The genetic variation was found between strains, and the genetic relationships between strains were close. At the similarity coefficient of 0.93, the 48 strains could be divided into four types. There was a certain correlation between genetic differentiation and geographical distribution. The results indicated that there were pathogenic differentiation and genetic variation among the grape downy mildew strains in different regions of Xinjiang.