基于SSR标记的80份烟草种质指纹图谱的构建及遗传多样性分析

Construction of Molecular Fingerprinting and Analysis of Genetic Diversity for 80 Tobacco(Nicotiana tabacum) Germplasms Based on SSR Markers

利用均匀分布于烟草24个连锁群上的48个SSR标记对80份烟草材料进行分析。结果显示,48个SSR标记共扩增出211个等位基因,平均每个标记4.396个,Shannon′s信息指数I为1.034,多态信息含量值为0.229～0.905,观测杂合度(Ho)、期望杂合度(He)和Nei′s多样性指数(H)平均值分别为0.320、0.572、0.431。聚类结果表明,在遗传距离为0.68时可以将80份烟草种质分为2个类群。5个烟草居群间的遗传一致度在0.643～0.765范围内,遗传距离分布在0.268～0.442。筛选4对核心引物构建了不同烟草种质资源的数字指纹图谱,可将这80份烟草种质资源全部区分开。本研究在分子水平上为筛选优质烟草种质资源、挖掘重要基因以及拓宽烟草育种遗传基础等工作提供科学依据。

80 tobacco germplasm resources were studied using 48 simple sequence repeat(SSR) markers distributeduniformly over 24 linkage groups of tobacco. Results showed that a total of 211 alleles among these germplasm wereidentified at all of 48 SSR markers loci, and an average of 4.396 alleles was observed for each primer pair with averageheterozygosity(Ho) 0.320, average expected heterozygosity(He) 0.572. Shannon′s index was 1.034, Nei′s index was0.431, and the PIC ranged from 0.229 to 0.905. These germplasm were divided into two groups at a genetic similaritycoefficient of 0.68 by UPGMA cluster analysis. The genetic identity among the five tobacco populations ranged from0.643 to 0.765, and the genetic distance ranged from 0.268 to 0.442. Four optimal pairs of core primers were used forthe DNA fingerprint construction. The study can provide reference for further tobacco germplasm resources searchwhich is important for genes discovery and exploitation.