中国豌豆地方品种SSR标记遗传多样性分析

利用21对豌豆多态性SSR引物, 对来自全国春、秋播区19省区市的1 221份豌豆地方品种进行遗传多样性分析, 共扩增出104条多态性带, 每对引物平均扩增出4.95个等位变异, 其中有效等位变异占62.52%。省份间SSR等位变异分布均匀, 但是省份间有效等位变异数、Shannon’s信息指数(I)差异明显, 省籍资源群间遗传多样性差异显著。遗传多样性以内蒙古资源群最高, 甘肃、四川、云南和西藏等资源群其次, 辽宁资源群最低。PCA三维空间聚类图揭示, 我国豌豆地方品种资源分化成3个基因库, 基因库I主要由春播区的内蒙古、陕西资源构成, 基因库II主要由秋播区最北端的河南资源构成, 基因库III主要由除上述省份之外的其他省区市的资源构成。UPGMA聚类分析表明, 不同省份资源群间的遗传距离变化范围为5.159~27.586, 中国豌豆地方资源据此聚类成2个组群8个亚组群, 与3个基因库的聚类结果相呼应。聚类结果显示, 我国豌豆地方品种资源群间遗传距离与其来源地生态环境相关联。

Genetic Diversity among Chinese Pea (Pisum sativum L.) Landraces Revealed by SSR Markers

A total of 1 221 pea (Pisum sativum L.) landraces from 19 provinces in spring sowing and winter sowing areas in China were employed for SSR analysis. One hundred and four polymorphic bands were detected by using 21 SSR primer pairs. 4.95 alleles were detected by each SSR primer pair on average, of which, 62.52% were effective alleles for diversity. SSR alleles were uniformly distributed in the landraces among provinces, while the number of effective alleles and Shannon’s information index (I) varied much among provincial based groups of genetic resources. Significant difference appeared in the majority of pairwise comparisons for genetic diversity between provincial based groups of genetic resources. Inner Mongolia possessed the highest level of genetic diversity (I = 1.066), followed by Gansu (I = 1.041), Sichuan (I = 1.026), Yunnan (I = 1.017) and Tibet (I = 0.996); Liaoning was the lowest (I = 0.515) in genetic diversity. Three gene pools were detected in Chinese pea landraces, which were polarized during its adaptation and cultivation in thousands years. Gene Pool I mainly consisted of the pea landraces from Inner Mongolia and Shaanxi provinces, Gene Pool II mainly consisted of the pea landraces from Henan province, and Gene Pool III mainly consisted of the pea landraces from other provinces except Shaanxi, Inner Mongolia and Henan. Pairwise Nei78 genetic distance among provincial based groups of pea landraces ranged from 5.159 to 27.586, 2 large cluster groups and 8 cluster sub-groups were identified based on the dendrogram interacting with the three gene pools. The clustering results of Chinese land-races reveal ecologically and geographically close correlation to their genetic diversity.