四川省不同地域的核盘菌遗传多样性分析

 核盘菌(Sclerotinia sclerotiorum)属于世界性分布的植物病原真菌,可以危害油菜等多种经济作物。研究不同地域核盘菌的遗传多样性对了解核盘菌的遗传演化过程和指导病害防控具有重要意义。实验采用序列相关扩增多态性(sequence-related amplified polymorphism,SRAP)标记对四川省17个不同地理来源的66株核盘菌菌株的遗传多样性进行了分析。10对检测引物共获得129个位点,其中123个为多态位点,占95.35%。UPGMA聚类结果显示,在相似性系数为0.7时,66个核盘菌菌株分为5类(Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ),分别包含60、2、2、1和1个菌株。在相似性系数为0.74时,第Ⅰ类又可分为3个亚类(Ⅰ-1、Ⅰ-2、Ⅰ-3),分别包含21、37和2个菌株。聚类及组成分分析结果显示,四川省各地区的核盘菌菌株具有较高的遗传多样性,但其遗传变异与菌株地理来源无明显相关性。

Genetic diversity of Sclerotinia sclerotiorum isolates from different regions in Sichuan province by SRAP markers

Sclerotinia sclerotiorum is a worldwide pathogenic fungus causing serious diseases on many economically important crops. Studying on the genetic diversity of S. sclerotiorum isolates from different eco-geographical regions is crucially important for understanding the evolution of this fungal pathogen and disease control. In this study, DNA polymorphism of 66 S. sclerotiorum isolates derived from 17 different regions in Sichuan pro-vince were detected using sequence-related amplified polymorphism (SRAP) markers. A total of 129 scorable fragments were identified with 10 SRAP primer combinations, among which 123 were polymorphic loci (95.35%). UPMGA (Unweighted Pair Group Method with Arithmetic Mean) indicated that the dendrogram consisted of five groups (Ⅰ, Ⅱ, Ⅲ, Ⅳ and Ⅴ) at the genetic similarity coefficient of 0.70, which included 60, 2, 2, 1 and 1 isolates, respectively. Moreover, the group Ⅰ contained three sub-groups (I-1, I-2, I-3) at the genetic similarity coefficient of 0.74, which included 21, 37 and 2 isolates, respectively. This study showed a rich SRAP polymorphism among the populations of S. sclerotiorum in Sichuan province, but genetic diversity had no significant correlation with geographical location.