72份紫橙色大白菜种质资源多样性分析

Diversity Analysis of 72 Purple-orange Chinese Cabbage Germplasm Resources

为了培育紫橙色大白菜新品种,丰富大白菜品种类型,利用表型性状和SSR分子标记对72份紫橙色大白菜自交系进行遗传多样性分析和类群划分。结果表明,表型性状聚类将72份紫橙色大白菜自交系分为4个类群,各类群分别包含13~24份种质,表明供试紫橙色大白菜自交系的形态类型比较丰富,各类群分布较均匀。SSR分子标记多样性分析平均Nei's基因多样性指数为0.274 5,Shannon's多样性信息指数为0.419 5,反映出供试紫橙色大白菜自交系遗传背景较为单一。SSR标记聚类将72份紫橙色大白菜自交系划分为5个类群和2份独立的种质,各类群分别包含2~40份种质,类群间种质分布不均匀。SSR标记可以将多数系谱来源相同的种质聚在同一类群。Kappa一致性检验表明,表型性状聚类结果与SSR标记聚类结果一致性较差,其原因是表型性状与SSR标记的代表性、覆盖性及对应性方面不一致。

In order to breed new varieties of purple-orange Chinese cabbage and enrich the variety types of Chinese cabbage,the genetic diversity and group division of 72 purple-orange Chinese cabbage inbred lines were analyzed based on phenotypic characters and SSR molecular markers.The results showed that 72 purple-orange Chinese cabbage inbred lines were divided into 4 groups by phenotypic clustering,and each group separately contained 13-24 germplasm,indicating that the morphological types of purple-orange Chinese cabbage inbred lines were rich and evenly distributed in each group.The average Nei’s gene diversity index and Shannon’s diversity information index by SSR molecular marker were 0.274 5 and 0.419 5,respectively,which indicated that the genetic background of purple-orange Chinese cabbage inbred lines was relatively simple.SSR marker clustering divided 72 purple-orange Chinese cabbage inbred lines into 5 groups and 2 independent germplasm,with each group containing 2-40 germplasm,and the germplasm distribution among groups was uneven.The results of SSR marker could cluster most germplasm with the same pedigree sources into the same group.Kappa consistency test showed that the clustering results of phenotypic traits were not consistent with those of SSR markers,which was a result of phenotypic traits were inconsistent with SSR markers in representativeness,coverage and correspondence.