基于SSR标记的苜蓿种质资源遗传多样性与群体结构分析

摘要

种质资源遗传多样性和群体结构的分析是进行复杂性状关联分析的前提条件.从140对SSR引物中筛选到16对多态性引物,对82份苜蓿(Medicago spp.)材料进行遗传多样性与群体结构分析.结果表明；16对SSR引物共检测出190个等位变异,平均11.88个；多态性比率66.67％～100％,平均为83.05％；基因多样性为0.1447～0.3637,平均为0.2577;PIC为0.0079～0.9432,平均为0.5501.群体结构分析表明,当K=5时△K最大,即82份苜蓿材料可划分为5个类群,其中75.61％的种质遗传组分相对比较单一,24.39％的种质遗传背景比较复杂.苜蓿种质资源遗传多样性丰富,群体结构的划分与种质的来源不完全相关.%Understanding the genetic diversity and population structure is a prerequisite for the association mapping of complex traits in a target population.Genetic diversity and population structure of 82 alfalfa materials were evaluated using 16 polymorphic SSR markers screened from a total of 140 SSR primer pairs.Results showed that a total of 190 alleles were amplified using 16 SSR primer pairs,with an average of 11.88 alleles per primer pair,the polymorphic rate averaged 83.05％,ranging from 66.67％～100％.The genetic diversity averaged 0.2577,ranging from 0.1477～0.3637,and the PIC averaged 0.5501,ranging from 0.0079～0.9432.Results indicated that △K had a maximum value when K=5,namely,these 82 alfalfa materials could be divided into 5 groups.75.61％Medicago germplasm were with single genetic components,the rest 24.39 ％ were with mixed genetic components.The genetic diversities of Medicago germplasm were abundant and the division of population structure was not completely related to germplasm source.