陕西7个毛樱桃自然居群遗传多样性的SSR评价

SSR evaluation of genetic diversity of seven wild Prunustomentosa populations in Shaanxi

【目的】研究陕西野生毛樱桃自然居群的遗传多样性，为科学保存和利用陕西野生毛樱桃资源提供理论依据。【方法】以陕西野生毛樱桃的7个自然居群140份样本为材料，用SSR分子标记技术研究其遗传多样性和遗传结构。【结果】用10对SSR引物从7个毛樱桃自然居群中共检测出92个等位基因，各引物扩增的条带数在6～14个。居群多态位点比率(PPL)为100%,Shannon’s 信息指数（I）平均值为1.280，Nei’s 基因多样性指数（H）平均值为0.655，可观察杂合度（Ho）平均值为0.584，期望杂合度（He）平均值为0.672，表明陕西7个毛樱桃自然居群具有较高的遗传多样性水平。居群的基因分化系数Fst=0.181，表明陕西野生毛樱桃的遗传变异主要存在于居群（81.9%）内，遗传分化居群内高于居群间，基于Fst测得基因流Nm为1.128。利用UPGMA对7个毛樱桃自然野生居群进行聚类，可以分为3类：麟游（LY）、绣房(XF)、华阴（HY）、哭泉（KQ）归为第1类，小峪（XY）为第2类，鹦鸽（YG）和青化（QH）归为第3类。【结论】李属植物SSR引物在毛樱桃上能够有效的转移利用，陕西毛樱桃自然居群具有较高的遗传多样性水平，其中华阴居群遗传多样性水平最高，遗传分化居群内高于居群间，7个居群可聚为3大类。

【Objective】This study investigated the genetic diversity of wild Prunus tomentosa populations to provide theoretic reference for utilization and conservation of thus resources in Shaanxi.【Method】A total of 140 samples from seven wild Prunus tomentosa populations in Shaanxi were collected to study genetic diversity and genetic structure using SSR markers.【Result】A total of 92 alleles of 10 loci were detected from seven wild Prunus tomentosa populations and the number of alleles per locus ranged from 6to14.The percentage of polymorphic loci(PPL)was 100%in populations.The mean Shannon's information index(I),Nei's gene diversity(H),observed heterozygosity(Ho),and expected heterozygosity(He)were1.280,0.655,0.584 and 0.672,respectively.The results revealed that the genetic diversity in the wild Prunus tomentosa of the 7populations in Shaanxi was rich.About 81.9%of(Fst=0.181)gene differentiation was observed within the populations,higher than among populations.According to gene differentiation coefficient,the gene flow(Nm)was 1.128.Based on un-weighted pair-group method,the seven wild Prunus tomentosa populations in Shaanxi were divided into three groups:group one included LY,XF,HY,and KQ,group two included XY,and group three contained YG and QH.【Conclusion】Genetic diversity inthe wild Prunus tomentosain Shaanxi was rich,and that of HY population was the richest.The genetic differentiation within each population was higher than among populations.And the 7populations were divided into 3groups.