中文摘要：

本研究对来自黑龙江、辽宁、河北、山东、江苏5个省12个黄瓜主产区的77个黄瓜霜霉菌菌株,采用SRAP分子标记进行了遗传多样性分析。从35对SRAP引物中筛选出10对引物,共产生9 554条扩增条带,其中9 132条表现多态性,占95.6%。基于SRAP分子标记,77个黄瓜霜霉菌菌株的遗传距离为0.60~1.00,表明黄瓜霜霉菌具有丰富的遗传多样性。通过聚类分析,77个黄瓜霜霉菌菌株聚类为8个类群,并且来自相同地区的菌株大多数聚集于同一类群中,表明黄瓜霜霉菌群体的遗传多样性与其地理来源密切相关。

英文摘要：

The genetic diversity of Pseudoperonospora cubensis isolates sampled from diseased cucumber plants in12 major cucumber-producing regions of 5 provinces,including Heilongjiang,Liaoning,Hebei,Shandong,and Jiangsu in China,was analyzed by sequence-related amplified polymorphism（SRAP）.Ten out of 35 SRAP primers used in the present study produced genomic DNA polymorphism in 77 P.cubensis isolates,amplifying a total of 9 554 bands,9 132 of which were polymorphic,accounting for 95.6%.The genetic distance of the 77 P.cubensis isolates ranged from0.60 to 1.00 based on analyses of the SRAP markers.The results showed that the P.cubensis populations presented a high genetic diversity and 77 isolates could be classified into 8 groups.Most of the isolates from the same area were clustered in the same group by using the UPGMA method,suggesting that the genetic diversity of P.cubensis isolates was related to their geographical origins.