滇西北地区冬虫夏草和阔孢虫草的遗传分化研究*

应用随机扩增多态性DNA（RAPD）技术对来自云南西北部高黎贡山和丽江玉龙雪山的6个冬虫夏草Cordycepssinensis（Berk．）Sacc．，来自德钦地区三个地方的8个阔孢虫草C.crassisporaZang，YangetLi以及来自云南昆明的一个蛹虫草C.militaris（Vuill）Fr．进行分析。18个随机引物获得的RAPD谱带清晰并呈现多态。遗传距离分析表明，冬虫夏草／阔孢虫草与蛹虫草之间存在显著的遗传差异。冬虫夏草与阔孢虫草之间的遗传差异较为明显。在同种虫草个体中，来自同一地方的样本间遗传差异较小，不同地方的样本间遗传差异较大。说明云南虫草的不同地理群体间存在遗传分化。应用UPGMA和NJ法构建的分子系统树将来自不同地方的冬虫夏草及阔孢虫草分别聚在一起，提示RAPD标记在虫草群体中有显著的地区特异性。RAPD作为有效的遗传标记，可在分子水平上研究虫草属的遗传分化、起源和系统演化等。

STUDY OF GENETIC DIVERGENCE IN CORDYCEPS SINENSIS AND C. CRASSISPORA FROM NORTHWESt OF YUNNAN BY USING RAPD

Random amplified polymorphic DNA (RAPD) was used in analyzing Cordyceps sinensis (Berk.) Sacc. and C crassispora from northwest of Yunnan Province (with a sample of C militaris (Vinll) Fr. used as outgroup). Using 18 arbitrary primers, each sample was distinguished from the others. Genehc distances of these samples were related tO their geographic distribution. Molecular phylogenetic trees constructed by UPGMA and NJ method clustered C sinensis and C crassispora,respectively. Samples from the same areas were clustered, and genehc divergences exist among different branches. Furthermore, our resultS implied that the RAPD markers indicate geographic specificity. Being a good genehc marker, RAPD is useful in studying genehc diversity and phylogeny of the genus Cordyceps.