目的 探究何首乌Polygonum multiflorum种质的遗传多样性和居群结构，为何首乌种质资源的保护及合理利用提供参考。方法 采用SRAP分子标记方法，利用Structure 2.3.4、NTSYSpc、Popgen 32和MEGA 7软件对数据进行统计，获得何首乌居群的多样性水平、遗传距离、遗传分化程度、聚类结果和群体分析结果。结果 何首乌野生居群遗传多样性大于栽培居群，多样性主要来自居群间。野生居群中，四川和重庆居群的遗传多样性较高，何首乌样品间遗传距离与地理距离无明显相关性；何首乌样品的邻接法（neighbor joining，NJ）聚类结果与地理分布相符，相同采集点样品可聚在一起。结果还显示农户栽培品亲缘关系近，说明品种间存在相互引种情况。居群结构分析表明，大部分何首乌样品的血缘组成较为单一，且K=16时，样品分类效果最佳，而分类结果则与NJ聚类基本一致。结论 SRAP分子标记是何首乌遗传多样性估计和种群关系的有效分析工具，而地形复杂性可能是影响何首乌遗传多样性程度的重要因素，另外，广西所产棱枝何首乌在何首乌种群中表现出特异性，与其他种源遗传距离大，支持将其列为何首乌的变种。

Objective To investigate the genetic diversity and population structure of Polygonum multiflorum germplasm, in order to provide reference for the protection and rational utilization of P. multiflorum germplasm resources. Methods Base on SRAP molecular marker method, the diversity level, genetic distance, genetic differentiation degree, clustering results and population analysis results of P. multiflorum population were obtained by using Structure 2.3.4, NTSYSpc, Popgen 32 and MEGA 7 software to make statistics on the data. Results The genetic diversity of P. multiflorum was mainly from intergroup, and the genetic diversity of wild population was greater than that of cultivated population. In the wild population, the genetic diversity was high in Sichuan and Chongqing population, and the genetic distance between samples of P. multiflorum had no obvious correlation with geographical distance; The NJ clustering results of the samples were consistent with the geographical distribution, and the samples from the same collection point could be clustered together. In addition, the results also showed that the cultivars of peasant households were closely related, indicating the existence of mutual introduction between the cultivars. Population structure analysis showed that most samples had single consanguinity, and the best classification result which was consistent with NJ clustering result could be obtained when K = 16 was used. Conclusion SRAP molecular marker technique is an effective analysis tool for genetic diversity estimation and population relationship studies of P. multiflorum. The complexity of terrain may be an important factor affecting the genetic diversity of P. multiflorum. In addition, P. multiflorum var. angulatum from Guangxi shows specificity in P. multiflorum population and has a large genetic distance from other provenances, therefore, it is suggested to classify it as a variety of P. multiflorum.

R286.12

广东省科技厅项目(2017A020213023)