利用13对SSR引物对2010年从湖南19个县(市)种植的44个水稻感病品种上分离到的169个稻瘟病单孢菌株进行了遗传多样性分析,结果在0.8的相似水平上将供试菌株划分为8个宗谱,其中L01宗谱为优势宗谱,占总菌株数的66.86%。病菌宗谱与菌株来源地及寄主品种之间关系复杂,来源于相同地区或来源于同一寄主品种的菌株亲缘关系相对较近,但不同地区稻瘟病菌生理小种分化程度不一,小种的分化程度与当地的地形地势以及该地区种植的水稻品种数量有一定关系。高海拔山区比丘陵区稻瘟病菌遗传多样性更丰富;在某一地区栽培品种组成多样化程度越高,该地区的稻瘟病菌遗传多样性越丰富。 Thirteen SSR primers were used to analyze the genetic diversity of 169 M. grisea isolates from 44 susceptible rice cultivars grown in 19 counties in Hunan province in 2010, The test strains were divided into 8 genealogies, of which the genealogical L01 was the dominant genealogy, accounting for 66.86% of the total number of strains. The relationship between the germline of the bacteria and the origin and host of the strains is complex. The strains from the same region or from the same host species have a relatively close genetic relationship, but different races of Magnaporthe grisea have different degrees of differentiation. The degree of differentiation is related to the local topography and the number of rice varieties planted in the area. The genetic diversity of Magnaporthe grisea in the hilly area of ​​high altitude is more abundant. The higher diversity of cultivated cultivars in a certain area, the more genetic diversity of Magnaporthe grisea in the area.