中文摘要：

采用RAPD技术对分离自我国的13株Epichlo（e） spp.和9株Neotyphodium spp.的禾本科植物内生真菌进行了遗传多样性分析,同时对其中的4株进行了rDNA-ITS序列分析及系统发育研究.RAPD分析结果显示：原产自我国的菌株与原产自欧洲的菌株N.uncinatum之间亲缘关系较远;我国的21个菌株之间也存在一定的遗传多样性.rDNA-ITS序列分析表明：原产自我国的菌株聚为一枝,表明我国的Neotyphodium属真菌很有可能直接由我国的Epichlo（e）属真菌演化而来的新的类群;我国的Epichlo（e）属真菌有可能和国外推测的一个未确定的Neotyphodium属真菌的杂交进化起源（LAC）有关.

英文摘要：

Random amplified polymorphic DNA （RAPD） analysis was used to characterize the genetic diversity of 13 isolates ofEpichlo~ spp. and 9 isolates ofNeotyphodium spp., the endophytic fungi of gramineous plants, obtained from grasses grown in China. According to the RAPD analysis, the isolates indigenous from China were distinctly different from those ofN. uncinatum native to Europe. The result showed that the abundant genetic diversity existed in Chinese isolates. Three Chinese isolates of Neotyphodium （N2, N6 and N12） and 1 Chinese isolates ofEpichloe （E3） were selected and subjected for the rDNA-ITS sequence analysis. All of these 4 isolates were clustered a distinct clade, which indicated that these isolates maybe a new taxonomical group, and Chinese Neotyphodium was possibly derived from Chinese Epichloe. The results also indicated that a Chinese Epichloe isolate （E3） was possibly phylogenetically related with Lolium-associated clade （LAC）, an ambiguous evolutionary source predicted in other studies.