安徽省水稻纹枯病菌致病力分化与遗传多样性

摘要

Thirty two rice sheath blight pathogen strains (Rhizoctonia solani) were isolated from the infected rice samples from seven distinctive areas of Anhui Province, and their pathogenicity and genetic diversity were analyzed.Pathogenic differentiation analysis indicated that the pathogenicity among the strains was significantly different.The pathogenicity of the majority isolates was moderate in Anhni province.The genetic diversity of 32 Rhizoctonia solani strains was analyzed by RAPD.The results showed that the pathogenic and genetic diversity among the tested isolates were high, the polymorphic rate was 98.2％, and the genetic similarity coefficients of the isolates were 0.62 - 0.84.All the strains could be classified into 4 groups at the similarity coefficient of 0.653, and most of the isolates from the same area were consistent, but the pathogenicity showed no significant correlation within the RAPD groups.%对分离自安徽省7个县(市)的32株水稻纹枯病立枯丝核菌在5个鉴别寄主上进行了致病力测定,分析了其遗传多样性.结果表明,水稻纹枯病菌各菌株间的致病力存在显著差异,安徽省水稻纹枯病菌中大多数为中等致病力.对这些菌株进行RAPD分析,结果显示,DNA多态率达98.2%,遗传相似性系数在0.62～0.84之间,表明水稻纹枯病菌遗传分化较大,群体结构多样性较丰富.在相似系数为0.653时,所有菌株可聚合为4类,聚合类型与菌株的地理来源相一致,菌株的致病力与RAPD聚类分析结果无相关性.