金花茶组物种遗传关系的ISSR分析

利用ISSR分子标记技术对广西南宁金花茶公园29份金花茶组物种进行遗传关系分析。筛选出的14条引物扩增得到133条清晰条带，其中126条为多态性条带，多态性位点百分比为94.74%。29份金花茶种质材料的Nei’s基因多样性指数为0.360 6，Shannon’s 信息指数为0.531 4，遗传相似系数介于0.481 0.835，金花茶组物种的遗传基础较宽。用NTSYS软件对样品进行UPGMA聚类分析，29份金花茶样品聚为3大类群，其中扶绥中东金花茶单独为一类，顶生金花茶和龙州金花茶聚为一类，其它金花茶聚为一类。分析结果表明：夏石金花茶和小花金花茶的遗传相似系数最高，支持将两者归并到柠檬黄金花茶；弄岗金花茶和毛籽金花茶亲缘关系很近，支持合并到同一个种；龙州金花茶和薄叶金花茶分别归为单独的种。

Genetic Relationships among Species from Camellia Sect. Chrysantha Chang Revealed by ISSR Analysis

Inter-simple sequence repeat (ISSR) technique was used to detect the genetic diversity and relationships in 29 samples of yellow camellias from Golden Camellia Park in Nanning, Guangxi Province. 133 discernible loci were obtained from all the samples by using 14 primers and 126 bands were polymorphic. The average percentage of polymorphic bands was 94.74%, Nei's gene diversity and Shannon's information index were 0.360 6 and 0.531 4, respectively. The genetic similarity coefficients among the tested samples ranged from 0.481 to 0.835, indicating a wide gene pool and much high gene diversity among species from Camellia Sect. Chrysantha Chang. A dendrogram showing genetic relationships among these samples was constructed by the unweighted pair-group method with arithmetic averages (UPGMA) based on Nei genetic similarity. According to the dendrogram, 29 materials could be divided into 3 groups. Camellia achrysantha formed the first group, C. pingguoensis var. terminalis and C. lungzhouensis were classified into the third group, and the others were classified into the second group. The results suggested that the similarity coefficient between C. xiashiensis and C. micrantha was the highest, and the two taxa should be merged into C. limonia; C. longgangensis and C. ptilosperma were closely related to each other, and they should be merged into the same species; C. lungzhouensis and C. chrysanthoides might be two distinct species.