基于ISSR数据探讨节茎曲柄藓(Campylopus umbellatus(Arn.) Paris)遗传多样性和居群遗传结构

选用简单序列重复区间扩增多态性(ISSR)分子标记,对分布于浙江清凉峰国家级自然保护区顺溪坞和凉源、浙江台州临海天台山、浙江舟山嵊泗列岛、江苏苏州天平山、广西上思十万大山、台湾宜兰县马告生态公园和云南西双版纳纳板河流域国家自然保护区8个自然居群的40份节茎曲柄藓(Campylopus umbellatus(Arn.) Par.)的遗传多样性进行了研究.应用筛选出的12条引物,共扩增出172条清晰、重复性高的条带.使用POPGENE 3.2分析发现:其中158条条带的多态性位点百分率(PPB)为91.86%,根井正利基因多样性指数(H)为0.292 2,香农-维纳多样性指数(I)为0.445 9,说明节茎曲柄藓居群遗传多样性水平较高.8个居群的遗传分化系数(G_(st))为0.634 6,居群间的基因流(N_m)为0.287 9,63.33%的遗传变异存在于居群间,36.67%的遗传变异存在于居群内,说明节茎曲柄藓居群间的遗传分化明显.基于ISSR数据的聚类分析表明:以遗传距离65为分组阈值,8个居群可被分为6组,节茎曲柄藓居群间的遗传分化主要由地理因素造成,居群内的遗传分化可能与生境的异质性有关.

The genetic diversity and genetic structure of the populations of Campylopus umbellatus (Arn.) Paris based on ISSR

To study the genetic diversity and population genetic structure characteristics of Campylopus umbellatus(Arn.) Paris,inter-simple sequence repeat (ISSR) marker technique method was used in the current study.40 individuals of 8 populations collected from Zhejiang,Jiangsu,Guangxi,Yunnan and Taiwan were detected by 12 ISSR primers.These primers generated 172 clear,repeatable bands.After analyzed by POPGENE 3.2 software,it was found that there were 158 polymorphic loci,of which the percentage of polymorphic bands(PPB) was 91.86%,Nei''s Genetic Diversity Index (H) was 0.2922,Shannon-Wiener Index (I) was 0.4459.The results indicated that the populations of Campylopus umbellatus has high level of genetic diversity.The genetic differentiation index (G_st) of the eight populations was 0.6346,the gene flow (N_m) among populations was 0.2879,and the majority of genetic variation (63.33%) exists among populations,only 36.67% exists in populations,which showed that Campylopus umbellatus has obvious genetic differentiation among populations.Based on ISSR data,the dendrogram with a grouping threshold at a genetic distance of 65 showed that populations could be divided into 6 groups.According to our analyses,the genetic differentiation among the populations of Campylopus umbellatus mainly is caused by geographical factors,which may related to the habitat heterogeneity.