Abstract:

In order to analyze the genetic diversity of Atractylodes chinensis （DC.） Koidz.， 158 A. chinensis germplasm resources from 16 populations were used as materials. The variation coefficient and diversity index of 13 phenotypic traits were analyzed， and the correlation analysis， principal component analysis and cluster analysis were performed. The genetic diversity was analyzed by SSR molecular markers. and the population structure was analyzed using Structure 2.3.4 software. The results showed that the coefficient of variation of 13 phenotypic traits of 158 A. chinensis germplasms ranged from 0.63% to 89.54%， and the variation coefficient of stem number was the largest. The Shannon-Wiener diversity index （H） ranged from 0.58 to 2.95， and main stem diameter was the highest diversity index. Correlation analysis showed that 13 phenotypic traits were correlated， among which plant height was significantly positively correlated with main stem diameter， leaf length， leaf width， stem number and crown width （P<0.05）. Principal component analysis showed that leaf width， crown width， stem number， lodging condition，flowering period and leaf color were the key factors affecting phenotypic traits of A. chinensis. Based on 13 phenotypic characters， 158 A. chinensis germplasms were divided into 3 groups. A total of 128 polymorphic bands were amplified by 17 SSR core primers， and the polymorphism rate was 88.56%. The variation ranges of Nei’s gene diversity index （h）， Shannon’s information index （I） and polymorphic information content were 0.03~0.41， 0.29~0.60 and 0.30~0.86， respectively. Based on 17 pairs of SSR markers， 158 A. chinensis germplasms were divided into 3 groups by UPGMA （unweighted pair group method with arithmetic mean） method. The analysis of population structure showed that 158 germplasms were divided into 3 groups， which 10 germplasms were mixed populations with complex genetic background. Comprehensive analysis showed that 60 germplasms of 158 A. chinensis germplasms were classified according to phenotype and SSR markers， and 20 germplasms were closely related， which indicated that geographical origin had a certain influence on the classification， but it was not a decisive factor. Above results provided theoretical reference for germplasm resources identification and selection of excellent germplasms for A. chinensis.

Key words: Atractylodes chinensis （DC.） Koidz., phenotypic character, genetic diversity, cluster analysis, population structure analysis

摘要：

为分析北苍术种质资源的遗传多样性，以16个居群158份北苍术种质为研究对象，分析13个表型性状的变异系数、多样性指数，并对其进行相关性分析、主成分分析和聚类分析；利用SSR分子标记进行遗传多样性分析，用Structure 2.3.4软件解析群体遗传结构。结果表明，158份北苍术种质的13个表型性状的变异系数为0.63%~89.54%，其中茎数的变异系数最大；Shannon-Wiener多样性指数（H）为0.58~2.95，其中主茎粗的多样性指数最高。相关性分析发现，13个表型性状间存在一定相关性，其中株高与主茎粗、叶长、叶宽、茎数、冠幅呈显著正相关（P<0.05）。主成分分析发现，叶宽、冠幅、茎数、倒伏情况、开花时期和叶色是影响北苍术表型性状差异的关键指标。基于13个表型性状聚类分析将158份北苍术种质划分为3个类群。17对SSR核心引物共扩增出128条多态性条带，多态率达88.56%；Nei’s基因多样性指数（h）、Shannon’s信息指数（I）和多态信息量分别为0.03~0.41、0.29~0.60和0.30~0.86；基于17对SSR分子标记，利用UPGMA（unweighted pair group method with arithmetic mean）法将158份北苍术种质划分为3个类群。Structure群体结构分析表明，158份种质划分为3个类群，其中10份种质为混合群体，遗传背景较为复杂。综合分析发现，158份北苍术种质基于表型和SSR标记聚类划分一致的有60份种质，其中20份种质亲缘关系较近，表明地理来源对北苍术种质资源类群划分有一定影响，但不是决定性因素。以上研究结果为北苍术种质资源鉴定与优良种质筛选提供了理论参考。

关键词: 北苍术, 表型性状, 遗传多样性, 聚类分析, 群体结构分析