基于SCoT分子标记的金花茶组植物种质资源遗传多样性分析

目的利用SCoT分子标记技术分析27份金花茶组植物种质资源的遗传多样性和亲缘关系,为金花茶组植物种质资源鉴定保护和开发利用提供理论依据。方法从100条SCoT引物中筛选出条带重复性好、多态性高的引物对供试材料进行PCR扩增,用NTsys 2.10e计算种质间的遗传相似系数,用非加权平均距离法(UPGMA)进行聚类分析,构建系统发育进化树。结果从100条SCoT引物中筛选出13条引物共扩增出566条条带,其中多态性条带549条,多态性比率为97%,平均每条SCoT引物扩增的总条带数和多态性条带数分别为43.54、42.23条,多态性比率为89.74%～100.00%,平均为96.82%;27份金花茶组植物种质间的遗传相似系数为0.367～0.754。聚类分析结果显示,遗传相似系数在0.480处可将27份金花茶种质划分为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ 5组,遗传相似系数在0.511处第Ⅰ组被划分为a、b亚组,在0.517处第Ⅱ组被划分为c、d亚组,在0.508处第Ⅳ组被划分为e、f亚组。结论不同金花茶组植物种质间的遗传多样性丰富,SCoT分子标记多态性高,重复性好,可有效用于金花茶组植物种质资源遗传多样性分析,为金花茶组植物种质资源的鉴定保护、分子辅助育种和开发利用提供理论依据。

Genetic diversity analysis of Camellia sect. chrysantha Chang germplasm resources based on SCoT molecular markers

Objective The genetic diversity and the genetic relationship was analyzed by using a molecule marker technique of SCoT in order to provide theoretical support and reference for the identification, protection, development and utilization of the 27 Camellia nitidssima sect. chrysantha chang germplasm resources. Methods SCoT primers with good repeatability and high polymorphism were screened out from 100 primers, the materials tested were amplified by PCR.Then the genetic similarity coefficient between different germplasms were calculated by using NTsys 2.10e. The cluster analysis of different germplasm resources was analyzed by using an unweighted pair-group method with arithmetic means (UPGMA) to construct phylogenetic evolution tree. Results A total of 566 bands were amplified from 13 primers which screened out from 100 SCoT primers, including 549 polymorphic bands, and the polymorphism was 97%. The average number of the total number of bands and polymorphic bands amplified from all primers were 43.54 and 42.23, respectively. The percentage of polymorphism bands (PPB) was between 89.74% and 100.00%, with an average of 96.82%. The genetic similarity coefficient between different camellia sect. chrysantha chang germplasm resources was between 0.367 and 0.754.The cluster analysis results show that 27 camellia sect. chrysantha chang germplasm resources could be divided into five groups at the genetic similarity of 0.480. They were group I, group II, group III, group IV and group V. The group I could be divided into a and b two subunit groups at the genetic similarity of 0.511. The group II could be divided into c and d two subunit groups at the genetic similarity of 0.517. The group IV could be divided into e and f two subunit groups at the genetic similarity of 0.508. Conclusion In a word, the different camellia sect. chrysantha germplasm resources present very rich genetic diversity. The SCoT molecular markers present high polymorphism and good repeatability, it can be effectively used for genetic diversity analysis of camellia sect. chrysantha chang germplasm resources and provide theoretical support and reference for the identification, protection, molecular assisted breeding, development and utilization of camellia sect. chrysantha Chang germplasm resources.