大蒜种质遗传多样性的SSR分析

为了探索中国大蒜种质个体的SSR位点的分布情况,为品种鉴定、保存及遗传改良提供分子生物学依据,利用6对SSR引物对40个大蒜(Allium sativumL.)品种进行聚类分析、主成分分析及遗传多样性评价。共检测到21个多态性位点,平均每对引物可扩增出约3.5条多态性片段,多态性百分率为56.76%;SSR引物组合平均有效等位基因数、Nei基因多样度和Shannon信息指数分别为1.5551、0.3414和0.5188。聚类分析显示,6对SSR引物可把40份大蒜种质资源从0.59相似系数水平上3个类群。第一类群包含28份种质,在相似系数为0.73的水平上进一步又被分成了3个亚类;第二亚类仅包含2份种质;第三亚类包含10份种质,在0.68的相似系数水平上分成了2个亚类。主成分分析和UPGMA的结果基本一致。不同地理来源的大蒜种质的Shannon-Weaver多样性指数的变幅为0.0576~0.4179,说明大蒜种质遗传多样性丰富。本研究利用SSR分子标记技术较准确地解析大蒜不同材料间的亲缘关系及遗传多样性,为中国大蒜SSR分子标记提供基础资料。

Genetic Diversity of Garlic (Allium sativum L.) Germplasm by Simple Sequence Repeats

In order to investigate the distribution of simple sequence repeats(SSR) loci of Chinese garlic germplasm and provide the basis for the cultivars identification, germplasm conservation, and genetic improvement, the cluster analysis, principal componet analysis and genetic diversity of 40 garlic(Allium sativum L.) cultivars were analyzed using six pairs of SSR primers. A total of 21 polymorphic loci among these materials and average 3.5 polymorphic loci per SSR primer were detected. The percentage of polymorphic loci was 56.76%; the mean effective number of alleles, the mean Nei’s gene diversity and the mean Shannon’s information index were 1.5551, 0.3414 and 0.5188, respectively. Results showed that 40 materials could be divided into 3 groups at the similarity coefficient level of 0.59, in which the first group consisted of 28 cultivars which included 3 subgroups at the similarity coefficient level of 0.73, and the second group consisted of 2 cultivars and the third group consisted of 10 cultivars which could be classified into 2 subgroups at the similarity coefficient level of 0.68. The result of principal components analysis was almost consistent with that of UPGMA clustering analysis. The change range of Shannon-Weaver information index was 0.0576~0.4179, which showed the garlic had abundant genetic diversity. The genetic relationship and genetic diversity of garlic germplasm can be assessed efficiently by SSR markers. This study provides basic information of SSR markers for Chinese garlic germplasm