基于EST-SSR标记的芒果品种遗传多样性与亲缘关系分析

为了研究广西大学芒果种质资源圃保存的43个芒果品种的亲缘关系,利用前期开发的EST-SSR分子标记对其遗传多样性和亲缘关系进行分析。结果显示,26对EST-SSR引物共扩增出140条条带,平均每对引物扩增出5.38条条带,其中多态性条带128条,平均多态性比率达90.79%。Nei’s遗传多样性指数(H),Shannon’s信息指数(I)和多态信息量(PIC)的平均值分别为0.346,0.516.和0.661,说明供试芒果品种存在着丰富的遗传多样性。供试芒果品种间相似性系数范围为0.54~0.91,平均为0.69。UPGMA聚类结果表明,在遗传相似系数为0.68处可以将供试芒果划分为3个小组(Ⅰ,Ⅱ和Ⅲ),其中组Ⅱ又可划分为4个亚组,划分结果与芒果品种的起源密切相关,但与芒果的种胚类型无关。本研究结果为芒果种质资源的收集整理和新品种的选育提供科学依据。

Analysis of Genetic Diversity and Relationship of Mango Varieties Based on EST-SSR Markers

To study the genetic diversity and genetic relationship of 43 mango varieties which were preserved in the mango germplasm nersery of Guangxi University,EST-SSR markers were used in this study.The results showed that,among the 43 varieties,26 pairs of primers marked by EST-SSR amplified 140 bands,with an average of 5.38 bands per each pair of primers,of which 128 were polymorphic bands,with the polymorphism rate of 90.79%.The average of Nei’s genetic diversity(H),Shannon’s information index(I)and Allelic polymorphism information content(PIC)were 0.346,0.516 and 0.661,respectively.This results showed that all the tested varieties were rich in genetic diversity.The genetic similarity coefficient of the tested mango varieties ranged from 0.54 to 0.91 with an average of 0.69.Clustering analysis based on the UPGMA method revealed that these 43 mango varieties could be divided into three groups at genetic similarities coefficient of 0.68.(Ⅰ,ⅡandⅢ),and the groupⅡcan be further divided into four subgroups.The clustering results were closely related to the origin of these mango varieties,but not related to the embryo type.The study would provide scientific basis for the management of mango germplasm resources and breeding of new varieties.