中国红、绿茶适制品种(系)遗传多样性与亲缘关系的SSR分析

Analysis of Genetic Diversity and Relationship of Tea Cultivars and Lines Suitable for Making Green and Black Tea Using SSR Markers

【目的】探讨中国红、绿茶适制品种(系)的遗传多样性和亲缘关系,了解遗传背景对于品种适制性差异的影响与作用,为茶树育种研究提供分子生物学方面的参考。【方法】利用自主开发的具有多态性的39对SSR引物对中国157份红、绿茶适制品种(系)进行遗传多样性评价和亲缘关系分析。【结果】引物在供试材料中平均可检测4.90个等位基因,11.28个基因型,平均多态性信息量(PIC)0.53,基因多样性指数(H)0.57,遗传分化系数GST 0.19,说明81%的遗传多样性来自品种之间的遗传差异。各省份供试材料的遗传多样性以广东最高,江西最低。按照适制性分组分析,结果表明适制红茶品种(系)的遗传多样性水平最高,红绿茶兼制型品种次之,适制绿茶品种(系)最低。根据育种方式分组分析表明,系统选育法得到的品种(系)其遗传多样性水平高于杂交选育品种(系),高于地方品种(系)。聚类分析显示,供试材料聚为了三大类,大部分品种(系)都按照其地理来源和遗传背景进行聚类,并未按照适制性相互聚类。【结论】中国红、绿茶适制品种(系)具有较高水平的遗传多样性。其中,适制红茶品种(系)的遗传多样性水平最高,红绿茶兼制型品种次之,适制绿茶品种(系)最低。同时,主要依据地理来源和遗传背景进行亲缘关系聚类。

[Objective] The genetic diversity and relationship of tea cultivars and strains suitable for manufacturing green and black tea were studied in order to learn the genetic effect on the manufacture suitability of tea plant and to provide some molecular information to support the effective tea breeding. [ Method ] The genetic diversity and cluster analysis of 157 cultivars and strains of tea plant were analyzed using 39 pairs of SSR markers. [Result] Totally 191 alleles and 440 genotypes were amplified by 39 SSR markers, with the average of 4.90 and 11.28. The average polymorphism information content （PIC） , genetic diversity （H） and genetic distance were 0.57, 0.53 and 0.65, respectively. Genetic diversity of tested tea cultivars and stains from Guangdong was higher than that from other provinces. Evaluated samples were classified by their manufacture suitability and the genetic diversity of black tea cultivars was higher than that of double-edged cultivars for both black tea and green tea and that of green tea cultivars. The level of genetic diversity among cultivars bred by individual selection was higher than that of cultivars bred by other methods. Almost all the tested cultivars and swains were clustered according to their geographic source and breeding source using UPGMA method rather than manufacture suitability. [Conclusion] The genetic diversity of 157 tested tea cultivars was relatively abundant and the most abundant genetic diversity was identified among cultivars suitable for making black tea. In addition, the samples were clustered based on geographic and breeding source.