新疆额尔齐斯河流域白杨派植物居群遗传多样性分析

Genetic Diversity of Section Leuce in Populus Along the Erqis River

应用SSR标记技术,对新疆齐斯河流域河谷分布的白杨派树种银白杨、银灰杨和欧洲山杨天然居群的克隆结构、克隆多样性和遗传多样性进行研究。结果表明:欧洲山杨、银白杨和银灰杨均有很强的克隆繁殖特性。欧洲山杨、银白杨居群的克隆多样性均比较高,Simpson指数分别为0.987和0.983。与欧洲山杨相比较,银白杨居群具有较低的遗传多样性,Shannon信息指数分别为1.068 9和0.324 9,Nei多样性指数平均为0.505 6和0.211 2。欧洲山杨和银白杨居群间的遗传一致度均较高,变幅分别为0.778 1 0.954 4和0.975 1 0.994 6,反映出其超长距离的基因流特性,超强的基因流阻止了银白杨和欧洲山杨居群的遗传分化。研究发现,银白杨和欧洲山杨分别有95%和89.98%的遗传变异存在于居群内。

Along the Erqis River, there are various natural Popultts forests, which lus, such as Populus alba , Populus canescens and Populus tremula. Clonal diversity include Section Leuce in Popu- and structure were studied using nuclear microsatellite markers. The results showed that clonal reproduction was the primary reproduction strategy of these Populus populations. The populations of P. alba and P. tremula had an abundant clonal diversity and the mean Simpson＇ s index were 0. 983 and 0.987, respectively. Compared with the P. tremula, Populus alba had low- er genetic diversity and their Shannon＇ index were 1. 068 9 and 0.324 9, Nei＇ index were 0.505 6 and 0.211 2, respectively. The genetic consistency was high among populations, and variation range were 0.778 1 - 0.954 4 in P. tremula, O. 975 1 - 0.994 6 in Populus alba. It suggested they had long-distance gene flow and prevented ge- netic differentiation among P. alba and P. tremula population. In addition, genetic diversity indicated that the genetic variation occurred within natural populations, which were 95% in P. alba, and 89.98% in P. tremula.