基于表型性状的孔雀草种质遗传多样性分析

Genetic Diversity Analysis of Tagetes patula Germplasm Based on Phenotypic Traits

为了了解孔雀草种质间的亲缘关系,提高孔雀草种质的利用效率,从18个形态特征对40份孔雀草种质进行了遗传变异分析、主成分分析及聚类分析。结果表明,孔雀草表型多样性丰富,种质间表型性状变异程度高,变异系数（CV值）范围3.92%~46.25%,以花朵数最大,其次是冠幅和株高;Shannon-Weaver多样性指数则以叶片性状及花性状较高,平均2.0以上。国内种质比国外种质多样性更丰富。通过主成分分析,筛选出对总体方差累计贡献率达78.949%的4个主成分,并筛选出综合性状表现良好的种质10份。参试的40份种质在欧氏距离阈值为7.29处可分为两大类,一类植株生长势较强包含2份种质（水星黄色和橙色）;其余38份种质为一类,在欧氏距离阈值为6.0处,又以花色差异可进一步划分为2个类群,说明生长势及花色可作为孔雀草种质依据表型性状分类的重要指标。

In order to understand the relationship and improve the use efficiency of Tagetes patula germplasm resources, analysis of genetic diversity and principal component of 40 Tagetes patula germplasms was carried out in terms of 18 traits. The results showed that the phenotypic diversity was abundant the higher ranged fro variation of phenotypes was detected among accessions in phenotypic m 3.92% to 46.25%, with the largest for flower number followed by in Tagete spatula germplasms, and traits. The coefficient of variation crown diameter and plant height. Shannon diversity indices indicated the higher diversity in frond （leaf） and flower traits with the average abpve 2.0. Moreover, the phenotypic diversity was more abundant in domestic germplasm than that in imported varieties. Four principal components with the variance cumulative contribution rate of 78. 949% were obtained and 10 accessions with better comprehensive characters were screened out based on the principal component analysis. When the Eu- clidean distance was about 7.29,40 accessions tested could be classified into two groups. The first group included 2 varieties （Shuixing yellow and orange）with the higher growth potential, and the second one containing 38 accessions that could be further divided into 2 sub-groups with flower color differences at the Euclidean distance about 6.0, suggestting that the growth potential and flower color may be considered as the important indicators for classification of Tagetes patula germplasm based on phenotypic traits.