基于反转录转座子及简单重复序列标记的裸大麦遗传多样性研究

Genetic diversity in hulless barley by retrotransposons-based markers and simple sequence repeat (SSR) markers

为揭示裸大麦育成品种与种质资源材料的遗传结构,利用反转录转座子标记(反转录转座子-微卫星扩增多态性,REMAP;反向反转录转座子扩增多态性,IRAP)与简单重复序列(SSR)标记,分析63份裸大麦的遗传多样性。IRAP、REMAP、SSR标记分别检测到315、143、38个等位变化,变异范围分别为9~58、7~25、2~4个,平均每对引物检测24.23、14.30、2.38个等位变化。REMAP和IRAP单一标记多态性位点贡献率高于SSR标记。反转录转座子标记揭示材料间遗传相似性系数(GS)为0.452~0.937,平均为0.674,在GS值0.620水平上将63份材料分为2大类,分别包含20份和43份材料。SSR标记结果显示材料间GS为0.351~0.973,平均为0.716,在GS值0.620水平上将63份材料区分为2大类,分别包含2份和61份材料。反转录转座子标记聚类结果在GS值0.740水平上能区分西藏野生资源和栽培资源,但SSR标记不能有效区分这2类材料。反转录转座子标记的主坐标及群体结构分析结果与GS聚类分析结果一致性较高;SSR标记群体结构与主坐标分析、GS聚类分析结果存在明显差异。本研究表明,裸大麦材料遗传背景简单,亚类间缺少基因交流,反转录转座子标记在裸大麦品种亲缘关系鉴定中有一定的优势。反转录转座子标记与SSR标记的协同使用可为裸大麦遗传多样性分析、种质鉴定及亲本选配揭示更多有用信息。

To evaluate the genetic structure of hulless barley,retrotransposons-based markers(retrotransposon-microsatellite amplified polymorphism,REMAP;inter-retrotransposon amplified polymorphism,IRAP)and simple sequence repeat(SSR)markers were used to obtain the genetic data of 63 hulless barley materials.The IRAP,REMAP and SSR markers detected 315,143 and 38 alleles,ranged from 9-58,7-25,and 2-4,with an average of 24.23,14.30,2.38 alleles per marker,respectively.The contribution rate of single retrotransposons-based marker polymorphic site was higher than that of SSR marker.As revealed by retrotransposons-based markers,the genetic similarity(GS)among these 63 accessions was from 0.452 to 0.937,with the average of 0.674.The accessions were divided into two subgroups at the GS level of 0.620,which contained 20 and 43 materials,respectively.As revealed by SSR markers,GS among these 63 accessions was from 0.351 to 0.973,with the average of 0.716.The accessions were divided into two subgroups at the GS level of 0.620,which contained 2 and 61 materials,respectively.The wild hulless barley accessions was clustered into a small category by the retrotransposons-based markers at the GS level of 0.740.However,it was unable to distinguish the wild hulless barley from the cultured by SSR markers in the present study.The population structure revealed by retrotransposons-based markers was consistent with the principal coordinate analysis and genetic similarity analysis.However,the population structure revealed by SSR markers showed difference.It was shown that most of the accessions were with single genetic components.The retrotransposons-based markers had advantage in the identification of the relationship of hulless barleys.And more genetic information could be explored by combining the retrotransposons-based markers and SSR markers.