濒危灌木长叶红砂遗传多样性的RAPD分析

RAPD analysis on genetic diversity of endangered shrub Reaumuria trigyna

应用RAPD分子标记对濒危灌木长叶红砂(Reaumuria trigyna)种群遗传多样性进行了分析。应用18条随机引物对长叶红砂5个种群的95个个体进行扩增,检测到118个位点,其中多态位点105个。结果表明:长叶红砂种群的多态位点比率(P)为88.98%,显示出长叶红砂种群存在较高的遗传多样性。Shannon多样性指数(0.4966)、Nei基因多样性指数(0.3303)和基因分化系数(Gst=0.1425)的分析结果显示,长叶红砂种群遗传变异大多存在于种群内,种群间的遗传分化占14.25%。聚类分析表明,长叶红砂种群遗传距离与地理距离之间无直接相关关系。遗传多样性水平与物种特性和所处不同群落有关,濒危植物并不一定表现为遗传变异水平的降低。

The genetic diversity of Reaumuria trigyna populations at different habitats was assessed by means of random amplified polymorphic DNA （RAPD） markers. A total of 95 individuals from 5 populations were studied, and 118 loci were detected by 18 random primers, among which, 105 were polymorphic. The mean proportion of polymorphic loci was 88.98% , indicating the high genetic diversity of the R. trigyna populations. The Shannon information index （0. 4966）, Nei＇s gene diversity index （0. 3303）, and gene differentiation coefficient among populations （Gst = 0. 1425 ） suggested that there were more genetic variations within population than among populations, and the genetic differentiation among populations were 14. 25%. Cluster analysis showed that there was no direct correlation between genetic distance and geographic distance. The genetic diversity was related to species traits and habitats. Endangered plant was not certainly displayed by lower genetic variation.