13个居群唐松草内部简单重复序列遗传多样性分析

Genetic diversity assessment in 13 populations of Thalictrum aquilegifolium detected by ISSR

目的:对13个居群唐松草进行遗传多样性分析。方法:通过改良的CTAB法提取DNA,并通过ISSRPCR扩增目的产物。结果:220条引物筛选出9条多态性较高的引物,共扩增125个位点,多态性比率100%。Popgene 1.32分析得出13个居群的Nei’s基因多样性指数(H)=(0.2523±0.1555),Shannon信息指数(I)=(0.3981±0.2033),遗传分化系数(Gst)=0.4282,基因流(Nm)=0.6676,可知群体间、群体内的遗传变异占总遗传变异的42.84%、57.16%,居群内的遗传变异高于居群间。与AMOVA分析相一致。Mantel检验表明种群间的遗传距离与地理距离较弱性正相关。表明13个居群唐松草有着较为丰富的遗传多样性且群体之间存在着一定的遗传分化。进行聚类分析和主坐标分析,表明每个居群的个体基本上会聚在一起,居群间基本不按地理位置的远近进行聚类。结论:13个居群唐松草的遗传距离和地理位置相关性不高。

Objective:To investigate the genetic diversity of 13 populations of Thalictrum aquilegifolium.Methods:DNA was extracted and amplified by improved CTAB protocol and ISSR-PCR.Results:A total of 9 primers with high polymorphism were screened from 220 primers.The 9 ISSR primers produced 125 amplified DNA fragments,and 125(100%)fragments were polymorphic.Its genetic structure was analyzed by Popgene 1.32 software,the result shown that the Nei’s gene diversity(H)and Shannon’s information index(I)were(0.2523±0.1555),(0.3981±0.2033),respectively,the genetic differentiation coefficient(Gst)was 0.4282 and the inter-population gene flow(Nm)was 0.6676,the genetic variation between and within populations accounted for 42.84%and 57.16%,and the genetic variation within populations was higher than that between populations.The results of AMOVA analysis were similar.Mantel showed that the positive correlation between genetic distance and geographical distance was weak.It could be concluded that 13 populations had abundant genetic diversity and certain genetic differentiation.Cluster analysis and(PCoA)analysis showed that the individuals of each population basically got together and the clustering could not be carried out basically according to the distance of geographical location.Conclusion:The genetic distance of the 13 populations of Thalictrum aquilegifolium have a weak relationship with the geographical location.