红景天Rhodiola rosea不同地理居群遗传多样性分析

Genetic diversity of different geographical populations of Rhodiola rosea based on AFLP markers

目的：研究分布于中国新疆天山地区红景天属植物定名种红景天Rhodiola rosea不同居群的遗传多样性。方法：野外采集18个不同居群红景天样本,进行AFLP分析,用POPGENE v1.31（32-bit）及SPSS软件分析处理数据。结果：从2套AFLP酶切系统（EcoRI/MseI）中筛选9对引物组合中共扩增出238条谱带,其中228条呈现多态性。等位基因平均数（Na）为1.488 3,有效等位基因数（Ne）1.390 7,Neis基因多样性指数（H）0.217 0,Shannons信息指数（I）0.310 8,多态性比率（P）为52.71%,居群间遗传分化系数（Gst）0.364;用UPGMA聚类分析,可将18个居群分为2个大类群。第Ⅱ大类群由6个居群组成,且均分布于海拔3 175 m以上;结论：海拔高度3 150～3 250 m分布的红景天居群遗传变异最为丰富,无论就地还是迁地保护该区域,对于拯救红景天种质资源都是非常重要的。

Objective： To research the genetic diversity of different Rhodiola rosea geographical populations in Tianshan Mountain, China; Method： The genetic diversity of eighteen R. rosea geological populations from six niches was estimated using amplified fragment length polymorphism （AFLP） markers. The data of amplified bands were analyzed by the software POPGENE vl. 31 （32-bit） and SPSS. Result： The nine primers employed produced a total of 238 discernable and reproducible amplified fragments. There were 228 polymorphic bands. The percentage of polymorphic bands with in different populations was 95.6%. Genetic diversity analysis showed that average number of alleles per loci was Na = 1. 488 3, effective number of alleles per loci Ne = 1. 390 7, Nei＇s gene diversity index H = 0. 217 0, Shannon＇s information index I = 0. 310 8, the percentage of polymorphic loci P = 52.71, genetic differentiation among populations Gst = 0. 364 ; UPGMA cluster analysis based on genetic distance data divided eighteen populations into two clusters ： Cluster Ⅰ composed of twelve populations and Cluster Ⅱ 6 populations which distributed in attitude upper 3 175 m; Conclusion： Our researches suggest that the best niche of R. rosea was at attitude between 3 150-3 250 m; this region is important for the conservation of R. rosea germplasm resource.