中国扁蓿豆种质资源遗传多样性的ISSR标记与生态因子相关性分析

Genetic Diversity of ISSR Markers and Environment Factors Correlation Analysis of Medicago ruthenica in China

采用ISSR分子标记技术对来自国内7个省市自治区的49个扁蓿豆居群的遗传多样性及生态因子的相关性进行分析,为扁蓿豆种质资源的保护利用提供理论依据和技术支撑。研究结果表明:采用筛选的15个条带清楚且稳定的引物,共获得127个扩增位点,其中,多态性位点110个,多态性位点的比例为85.61%,平均每个引物的多态扩增位点为7.33个;居群间基因多样性指数、Shannon指数、基因分化系数3个指标均大于地区间,内蒙古地区的遗传多样性较丰富,北京地区的遗传差异较小;聚类和主成分分析将49个扁蓿豆居群分为6大类,供试扁蓿豆种质资源呈现出较好的地域性分布规律;基因多样性指数、Shannon指数及多态位点百分率均与年降水量呈显著负相关。

In order to provide a theoretical basis and technical support for the protection and utilization of M.ruthenica,genetic diversity and environment factors correlation analysis were studied using ISSR molecular markers of 49 M. ruthenica collected from 7 provinces or autonomous regions of China. The results showed that 15 primers were selected which had clear polymorphic bands. A total of 127 bands,including 110 polymorphic bands,were detected by using the 15 selected primers,and the proportion of polymorphic fragment was 85. 61%,averaged 7. 33 bands for each primer pair. Nei＇s gene diversity index,Shanaon diversity and Gst of within pupolutions were greater than those of within regions. The genetic diversity was rich in Inner Mongolia and Tibet,the genetic differences in the Beijing was smaller. Based on cluster and principal component analyses,49 populations could be divided into 6groups. M. ruthenica germplasm resources presented a good regional distribution. Genetic diversity index,Shannon index and the percentage of polymorphic loci were significantly negatively correlated with annual rainfall.