对产自不同省区的何首乌[Fallopia multiflora ( Thunb.) Harald.]17 个野生居群 85 个单株的 psbA-trnH 序列进行了扩增和分析,在此基础上分析了居群间的遗传多样性,并采用 NJ 法对 85 个单株进行了聚类分析。 结果表明:供试 85 个单株的 psbA-trnH 序列长度为 384 bp;其中,变异位点为 167 bp,简约信息位点为 53 bp,分别占序列总长度的 43. 5% 和 13. 8% 。 变异类型主要为碱基缺失和替换;变异位点主要集中在 235 ~ 281 bp 区域,根据位点变异情况可将17 个居群大体分为3 类。 各居群间的遗传距离为0. 000 ~ 0. 172,其中,贵州居群与其他16 个居群间的遗传距离为 0. 167 ~ 0. 172,而其他 16 个居群间的遗传距离为 0. 000 ~ 0. 017。 17 个居群间的核苷酸多样性指数(Pi)、遗传分化系数(Nst)和基因流(Nm)分别为 0. 028 56、0. 918 68 和 0. 04;除贵州居群外其他 16 个居群的 Pi、Nst 和 Nm 分别为 0. 015 68、0. 837 19 和 0. 10;贵州居群与其周边省区(四川、云南、广西、湖南和湖北)居群的 Pi、Nst 和 Nm 分别为 0. 047 99、0. 937 62 和 0. 03。 在 NJ 系统树上,17 个居群可聚为 4 支,且大部分居群的供试单株聚在同一分支中;仅贵州居群单独聚为一支,与序列分析的划分结果基本一致。 由研究结果可见:野生何首乌居群总遗传变异的 91. 868% 来自居群间,8. 132% 来自居群内,居群间的基因交流较少;除贵州居群外其余 16 个居群的整体遗传多样性水平偏低,说明何首乌居群整体多样性水平在很大程度上受贵州居群的影响。

Sequence of psbA-trnH of 85 individuals in 17 wild populations of Fallopia multiflora (Thunb.)Harald. from different provinces and regions in China was amplified and analyzed, and on the basis,genetic diversity among populations was analyzed and cluster analysis of 85 individuals was also carried out by NJ method. The results show that the length of psbA-trnH sequence of 85 individuals is 384 bp, in which, there are 167 bp variable sites and 53 bp parsimony informative sites, accounting for 43. 5% and 13. 8% of the total length of sequence, respectively. Variable types are mainly base deletion and substitution. Variable sites mainly concentrate in the region of 235-281 bp. 17 populations are almostly divided into three types according to site variation status. The genetic distances among 17 populations are 0. 000-0. 172, in which, genetic distances between Guizhou population and other 16 populations are 0. 167- 0. 172, and those among other 16 populations are 0. 000 - 0. 017. Nucleotide diversity index (Pi), coefficient of gene differentiation (Nst) and gene flow (Nm) among 17 populations are 0. 028 56, 0. 918 68 and 0. 04, respectively. Pi, Nst and Nm among other 16 populations except Guizhou population are 0. 015 68, 0. 837 19 and 0. 10, respectively. And Pi, Nst and Nm between Guizhou population and its neighboring populations ( Sichuan, Yunnan, Guangxi, Hu’nan and Hubei) are 0. 047 99, 0. 937 62 and 0. 03, respectively. On NJ phylogenetic tree, 17 populations are clustered into four branches and individuals tested in most populations are clustered in a same branch and only Guizhou population is clustered alone in a branch, which is basically same with the deviation result by sequence analysis. It is suggested that 91. 868% of overall genetic variation of 17 wild populations exists among populations and 8. 132% within populations, and gene exchange among populations is less. Except Guizhou population, overall genetic diversity level among other 16 populations is low, indicating that the overall diversity level of F. multiflora populations is affected by Guizhou population at a large extent.