基于表型性状和EST-SSR分子标记的参薯种质资源遗传多样性分析

Genetic Diversity Analysis of the Germplasm Resources of Greater Yam Based on Phenotypic Traits and EST-SSR Markers

为明确中国南方8个省份收集的42份参薯栽培种的遗传背景,本研究利用表型性状和EST-SSR标记分析该种质资源群体的遗传多样性。结果表明,11个表型性状的变异系数区间为9.52%~80.95%。根据11个表型性状,对42份参薯种质资源进行聚类分析,发现这些种质资源可被分为两个主要类群。此外,利用83对EST-SSR引物共筛出56对具有多态性,共扩增到117个条带,其中102个为等位变异位点,每对引物检测出的多态性位点为1~4个,每个引物平均多态性位点为1.82个。采用NTSYS-pc 2.10对EST-SSR标记扩增位点获得的基因型数据进行分析,发现42份样品遗传相似性系数介于0.367 3~0.935 1之间,平均值为0.651 2,当遗传相似性系数为0.674 0时,可将42份样品划分为三大类。本研究结果说明中国南方参薯具有较丰富的遗传多样性,为进一步的特异种质资源的筛选提供理论依据。

In order to elucidate the genetic background of 42 Dioscorea alata(greater yam)collected from 8 provinces in southern China,this study utilized both phenotypic traits and EST-SSR markers to analyze the genetic diversity of this germplasm population.The results showed that the coefficient of variation for 11 phenotypic traits ranged from 9.52%to 80.95%.Based on these 11 phenotypic traits,a cluster analysis was conducted on the 42 greater yam germplasm resources,which led to the identification of two main groups within this population.Furthermore,83 pairs of EST-SSR primers were employed to screen for polymorphisms,resulting in a total of 56 polymorphic primer pairs and 117 amplified bands.Among them,102 were identified as allelic variations,with each primer detecting 1 to 4 polymorphic loci,and an average of 1.82 polymorphic loci per primer.The genotype data obtained from the amplified bands of the EST-SSR markers were analyzed using NTSYS-pc 2.10,and the genetic similarity coefficients of the 42 samples ranged from 0.3673 to 0.9351,with a mean value of 0.6512,when the genetic similarity coefficient was set at 0.6740,the samples could be classified into three major groups.These research findings indicate that greater yam in southern China possess considerable genetic diversity,providing a theoretical basis for further screening of unique germplasm resources.