Abstract: Three hundred and twenty four Magnaporthe grisea isolates from rice in China were analyzed by rep-PCR for genetic diversity. DNA fingerprint patterns of the isolates showed that there were many differences among the isolates from different areas. In 20 genetic lineages of M. grisea, CL20 is dominant one in China. All isolates could be classfied into two groups by DNA fingerprint patterns. CN stands for M. grisea from Jiangsu, Zhejiang and North China; CS stands for isolates from Guangdong, Sichuan, etc. Result showed that variation of M. grisea from rice in China is related with variety distribution and climate conditions.

Key words: Magnaporthe grisea, population structure, DNA fingerprint pattern, polymorphism

摘要： 利用Pot2-rep-PCR技术对收集自我国14个省水稻产区的324个稻瘟病菌株进行了DNA指纹分析。稻瘟病菌在DNA水平上的变异比较高，具有很丰富的多态性；在20%的遗传距离水平上，170个单型被划分成20个遗传系谱，其中CL20是绝对优势系谱；对病菌系谱的地区分布分析发现，不同地区之间稻瘟菌的群体结构差异是明显的，但是也有部分菌株属于相同的系谱甚至是同一单型；14个省稻区的菌株指纹图谱可以分为明显的两类，江浙、北方等省稻区菌株的DNA指纹相似程度比较高，南方9省稻区菌株DNA指纹相似程度比较高，这可能与两类地区的主栽品种类型不同有关。

关键词: 稻瘟病菌, 群体结构, DNA指纹图谱, 多态性