基于SSR标记的紫花风铃木群体遗传多样性分析

为揭示紫花风铃木(Handroanthus impetiginosus)的群体遗传变异特征，对广东省6市12个群体72份种质材料进行遗传多样性和群体遗传结构分析。结果表明，9对引物共扩增出123个等位基因位点，引物的平均多态信息量为0.754，具有较高的多态性。12个群体均具有较高的遗传多样性，群体间平均有效等位基因数为3.272个，平均Shannon指数为1.159。AMOVA分析表明群体间遗传分化程度相对较低，群体内遗传分化程度较高。群体的总体遗传分化系数为0.077，处于中等程度。基于Structure分析、主坐标分析和NJ聚类分析均可将12个群体分为2大类群，分组结果具有一定相似性，表明供试紫花风铃木群体遗传结构较为简单。这为紫花风铃木优良种质资源的利用、遗传变异和科学育种提供了理论参考。

Genetic Diversity Analysis of Handroanthus impetiginosus Populations by SSR Markers

Handroanthus impetiginosus, introduced from South America and Central America, had widely used as ornamental tree in southern China, which had rich germplasm resources. However, the resources of introduction is complex while the work of improved variety breeding is lagging. In order to reveal genetic variation of H. impetiginosus populations, the genetic diversity and population genetic structure of 72 samples from 12 populations collected from 6 cities in Guangdong Province were analyzed. The results showed that a total of 123 alleles were amplified by 9 pairs of SSR primers with average PIC of 0.754, indicating that the H. impetiginosus germplasm had high genetic diversity. All 12 populations of H. impetiginosus also had high genetic diversity, the average effective alleles between populations was 3.272, and the average Shannon information index was 1.159. AMOVA analysis showed that genetic differentiation among populations was relatively low, while that within populations was high. The overall genetic differentiation coefficient of populations was 0.077, which was in the medium degree. Based on the Structure analysis, PCoA analysis and NJ clustering analysis, 12 populations of H. impetiginosus could be divided into 2 groups, and the grouping results had certain similarity, indicating that the genetic structure of tested populations was not complex. These would provide a theoretical basis for the utilization of germplasm resources, genetic variation and scientific breeding for H. impetiginosus.