应用ISSR技术分析不同分离方法获得的冬虫夏草菌株的遗传多样性

从60个引物中筛选出7个扩增条带清晰且多态性好的ISSR引物,并摸索合适的PCR反应条件,用于40株冬虫夏草的无性型——中国被毛孢菌株的PCR反应,共得到62条带,其中多态性条带38条,多态性百分率仅为61.29%,遗传相似系数范围在0.78¹.00之间。非加权配对算术平均法(UPGMA)聚类分析的结果表明:40株中冬虫夏草无性型菌株并没有完全按照不同的分离方法聚为3个类型;单子囊孢子分离法获得的菌株,明显区别于其他菌株而单独聚为一类,其他菌株则混合聚类。

Study on Genetic Diversity of Anamorphic Isolates from Different Sources of Ophiocordyceps sinensis by ISSR

Hirsutella sinensis is the anamorph of Ophiocordyceps sinensis. The PCR reaction condition for 40 isolates of Hirsutella sinensis was optimized. A total of 62 amplified fragments were obtained using 7 ISSR primers,38 of them（ 61. 29%） showed polymorphism. The 40 isolates had a Jaccard similarity with coefficient at 0. 78-1. 00. The cluster analysis was applied by unweighted pair-group method with arithmetic means（ UPGMA） that 40 isolates did not cluster into 3 groups according to different isolation methods. The strains,isolated by the method of the single ascospore isolation,were clustered into one group only and other isolates were mixed together. The findings suggest that the isolates from same place had certain genetic differentiation and ISSR fingerprinting of the single ascospore isolate was significantly different from other isolates.