基于SSR标记的大麦种质资源遗传多样性分析

Assessment of the Genetic Diversity of Barley Germplasm Resources Based on SSR Markers

了解现有大麦种质资源的遗传多样性,将为大麦杂种优势利用及新品种选育工作提供理论依据。在对416对SSR引物进行筛选的基础上,挑选出54对条带清晰且多态性稳定的引物,对157份国内外大麦种质资源(以长江中下游麦区育成品种为主)进行了遗传多样性分析。聚类分析结果表明,参试品种的遗传相似系数(GS)分布在0.5428~0.9304。在GS为0.6657水平时,可将参试品种分为5个亚群。进一步分析表明,来自湖北省的鄂大麦品种(系),除鄂大麦10号、鄂大麦7号、鄂大麦9号、鄂大麦6号外,都聚在第五大类第二亚类,而河南省驻大麦品种(系)大多聚在第四大类。材料的来源与聚类分析的结果基本一致,说明长期以来,各育种单位在品种选育中,普遍存在资源利用范围较为狭窄,遗传基础较为单一的情况。因此,在未来的育种过程中,注意充分利用遗传关系比较远的材料进行杂交选育,将更有助于在后代中选择出综合性状优异的新种质。

Assessment of the genetic diversity of barley germplasm resources will provide a theoretical basis for the effective utilization of barley heterosis and the breeding of superior barley varieties.In the current study,157 barley accessions were evaluated for their genetic diversity based on 54 SSR primer pairs which were selected from 416 SSR primer pairs.The clustering analysis showed that the genetic similarity coefficients(GS)of the tested varieties were in the range of 0.5428~0.9304,and the 157 barley accessions were divided into five groups at the GS reaching 0.6657.The further analysis showed that all accessions from Hubei Province except for the accessions Edamai 6,Edamai 7,Edamai 9,and Edamai 10 were clustered into the second subgroup of Group 5,while the accessions from Henan Province were clustered into Group 4.This indicated that the sources of the barley accessions were consistent with the results of the clustering analysis,revealing the problem that in barley breeding,the materials used by most barley breeders had a narrow genetic basis,which could bring the risk of yield decrease under an adverse environment.Thus,it is necessary to choose barley germplasm resources with a wide genetic basis for barley breeding in the future.