RAPD标记研究新疆胡杨五个地理种群的遗传分化

目标：对新疆地区塔里木盆地、准噶尔盆地和吐鲁番盆地的天然胡杨5个地理种群进行研究,科学评价地理隔离和遗传多样性的关系。方法：CTAB法提取DNA,RAPD分子标记分析5个天然胡杨种群的遗传结构。结果：筛选出的10个随机引物总共扩增出133个条带,其中84.96%为多态性,5个地理种群的种间遗传多样性0.0601～0.3081,Shannon’s指数0.2087～0.3332之间,Gst数据表明60.51%的遗传变异存在于种群内。结论：基于Nei’s遗传距离的UPGMA聚类分析显示：塔里木和吐鲁番盆地的胡杨种群相比准噶尔盆地种群有更近的遗传关系,胡杨通过两个途径传入新疆,造成遗传分化的因素主要与胡杨在新疆特殊地理环境下的发展历史及生态适应有关。

Study on Geographical Isolation and Genetic Diversity of Populus euphratica in Three Basins of Xinjiang by RAPD Analysis

Objective:Populus euphratica plays an important role in the maintenance of the structure and function of ecosystems in arid or semiarid area.The aim was to investigate the genetic diversity and structure of natural P.euphratica populations in three geographically isolated basins (Tarim,Junggar and Turpan Basin) all over the Xinjiang.Method:Eighty-five individuals were analyzed using the technique of RAPD,and the genetic diversity and structure were analyzed by NTSYSpc and POPGENE software.Result:Ten primers amplified 133 bands,with 113 (84.96 % ) being polymorphic.The inter-population genetic variability was 0.0601-0.3081,and the range of the mean intra-population genetic distances was 0.2087-0.3332.P.euphratica populations held more genetic variation (60.51% ) within populations.The result of cluster analysis showed that the populations of Tarim Basin and Turpan Basin form groups were genetically distant from Junggar Basin.Conclusion:The dendrogram inferred that the distribution and expand of P.euphratica into Xinjiang have been processed through two different pathways,and Tian Shah Range has affected gene exchange or diffusion.The results will have practical applications for breeding,conservation and the clarification of the mechanisms of species differentiation.