辽宁省白头翁叶斑病菌的遗传多样性

Genetic diversity of Ascochyta anemones isolates in Liaoning Province of Northeast China

白头翁叶斑病是近年来我国新报道发生的一种白头翁叶部病害,在辽宁省保护地白头翁生产中病害尤为严重.对采自辽宁省5个白头翁主产区的25株白头翁叶斑病菌(Ascochyta anemones)菌株及中国农业科学院惠赠的5个壳二孢属(Ascochyta spp.)菌株进行RAPD分析.结果表明:11条随机引物共扩增得到条带清晰并呈多态性的108条谱带,单个引物扩增DNA片段集中分布在200～2000bp.采用NTSYS软件进行病原菌的聚类分析,发现供试的30株壳二孢菌的遗传相似系数为0.56～0.98,当相似系数为0.62时,30个菌株被划分为4个类群,说明辽宁省白头翁叶斑病菌具有丰富的遗传多样性.RAPD遗传聚类组群与白头翁叶斑病菌菌株的地理来源有一定的相关性,不同寄主来源的菌株之间存在明显的遗传差异.

Windflower leaf spot is a newly reported leaf disease in China, and becomes very serious in the protected field of windflower （Pulsitilla chinensis） in Liaoning Province. In this study, a ran- dom amplified polymorphic DNA （RAPD） analysis was made on the 25 Ascochyta anemones isolates from 5 main P. chinensis production areas in the Province and 5 Ascochyta spp. isolates presented by the Chinese Academy of Agricultural Sciences. A total of 108 polymorphic DNA bands sized 200-2000 bp were obtained by using 11 random primers. The NTSYS cluster analysis showed that the genetic similarity coefficient of the 30 Ascochyta isolates was 0.56-0.98, and these isolates could be divided into 4 genetic groups when the similarity coefficient was 0.62, suggesting that the pathogens of windflower leaf spot in the Province had rich genetic diversity. There existed definite correlations between the RAPD clustering groups and their geographic distribution, and an obvious genetic difference among the isolates from different host sources.