4个滇牡丹天然居群遗传多样性的ISSR分析

ISSR Analysis of Genetic Diversity among 4 Natural Populations of Paeonia delavayi

以云南省香格里拉县4个滇牡丹天然居群为研究对象,采用ISSR分子标记技术,对98份材料进行遗传多样性分析,用多态性高、稳定性强的10条引物进行扩增,共获得96条扩增产物,其中多态性条带有82条,多态性百分比为85.42%;滇牡丹总体基因多样性为0.343 8,Shannon指数为0.500 9;通过Nei’s和聚类分析,居群间的遗传分化系数为0.797 3,居群间的遗传变异占总遗传变异的79.73%,而居群内的遗传变异只有20.27%,表明滇牡丹居群间的遗传分化较大,遗传变异主要存在于居群间。因此,滇牡丹虽然为分布区狭窄的特有种,但是与一些典型稀有和濒危的物种相比,遗传多样性并不低,滇牡丹的分布区域和种群数量呈现狭窄化、缩小化的趋势,主要原因是受人为过度采挖,生境受到破坏所致。

ISSR molecular marker technology was used to analyze genetic diversity of 4 natural populations of 98 Paeonia delavayi individuals from shangrila in Yunnan .10 primers with high polymorphism and steady expansion were selected and 96 bands were identified , of which 82 bands were polymorphic , the polymorphism percentage was 85.42 %.The total genetic diversity of 98 Paeonia delavayi was 0.343 8, and the Shannon index was 0.500 9 .Through the Nei ’ s and Cluster analysis , the gene differentiation coefficient among populations was 0.797 3, the genetic variation among populations was 79.73%, the genetic variation within populations was only 20.27 %.All of these indicates that the different populations of Paeonia delavayi had a larger genetic differentiation, and the main genetic variation was existed among populations .The study also showed that although Paeonia delavayi was an endemic species , compared with some typical rare and endangered species , its genetic diversity was not low .The reason of its narrowing distribution tendency was mainly caused by over collection and habitat dis turbance from human activities .