滇杨遗传多样性的SRAP分析

Genetic Diversity Analysis of Populus yunnanensis by SRAP Markers

采用SRAP标记分析滇杨的遗传多样性和遗传结构。用筛选出的7对引物组合分析来自7个居群共208个样本,共扩增得到条带146条,多态性条带73条,多态带百分率为50%。滇杨物种水平上的观测等位基因数(Na)为1.500 0,有效等位基因数(Ne)为1.230 9,Nei’s基因多样性指数(H)与Shannon’s信息指数(I)分别为0.136 6与0.210 0。遗传分化系数(Gst)为0.529 4,基因流(Nm)为0.444 4,表明居群间的遗传变异大于居群内,其基因交流处于中等水平。AMOVA分析也表明居群间的变异占总变异的55.61%。UPGMA、PCo A和Bayesian聚类分析结果一致,均显示丽江与曲靖居群、楚雄与昭通居群的亲缘关系较近。Mantel test结果表明滇杨居群间的遗传距离与地理距离不相关。

To figure out the genetic diversity and genetic structure of Populus yunnanensis,208 samples from 7 populations were analyzed by sequence-related amplified polymorphism（SRAP）markers. With selected 7 pairs of primers,146 bands were obtained,in which 73 fragments（50%）were polymorphic. The values at the species level were 1.500 0 for observed alleles number（Na）,1.230 9 for effective alleles number（Ne）,0.136 6 for Nei＇s genetic diversity index（H）,and 0.210 0 for Shannon＇s information index（I）. The genetic differentiation coefficient（Gst）was 0.529 4 and gene flow（Nm）was 0.444 4 and on intermediate stage,indicating that genetic variability of P. yunnanensis mainly took place among populations. Similarly,AMOVA showed that the genetic diversity among populations accounted for 55.61% of total. Clustering analysis by UPGMA,PCo A and Bayesian constantly revealed that population Lijiang and Qujing were in close relationship,and the same for population Chuxiong and Zhaotong. In addition,no correlation between the genetic distance and geographical distance was found by Mantel Test.