基于RAPD的群体标记法分析苜蓿种质遗传多样性

Genetic Diversity of Alfalfa(Medicago sativa) Germplasm using Bulked DNA Based on RAPD Markers

苜蓿种质资源的分子遗传多样性分析对于种质资源保存和育种利用具有重要指导意义。本研究选用群体标记法对来自甘肃省的16个苜蓿品种的DNA进行RAPD扩增,旨在研究其遗传多样性,并在此基础上筛选品种特异性引物用于进一步的品种鉴定。依据16个苜蓿品种间的Roger’s遗传距离进行UPGMA聚类分析结果显示,品种间亲缘关系与其选育背景紧密相关,供试的16个品种被划为4个类群,其中,匍匐型品种Jindera与其他直立型品种差异显著,自成1个类群,引进品种和甘肃省内具有国外种质来源的育成品种被划为同1类群,而甘肃地方品种聚为2个类群。10个RAPD引物中有4个引物OPE4、OPE5、OPE6和OPE7分别检测到5个品种甘农3号、甘杂27、Jindera、陇东和Algonuin的特异性条带,可进一步用于开发设计特异性引物进行品种鉴定工作。以上结果进一步证实,利用RAPD标记研究苜蓿系谱发育关系和选择杂交亲本应采用群体标记法。

Analysis of molecular genetic diversity in Alfalfa（Medicago sativa L.）germplasm is of great importance for conserving and breeding programs.The objective of this study was to evaluate the genetic diversity of alfalfa varieties,and to identify them through screening the variety-specific primers.This report analyzed the genetic diversity of 16 alfalfa varieties from Gansu Province based on RAPD markers using bulking equal quantities of DNA from 20 individuals of a cultivar.Based on the Roger＇s distances between the sixteen cultivars,the dendrogram by UPGMA cluster analysis showed that the relationships among these cultivars were tightly related to breeding programs.There was a clear difference between creeping variety Jindera and other erect varieties.Within the erect accessions,3 distinct groups including one introduced varieties and synthetic varieties originated from alien germplasm,one east-central group and one west group,were detected.Four of 10 primers,OPE4,OPE5,OPE6 and OPE7,amplified the specific bands belong to 5 cultivars,Gannong 3,Ganza 27,Jindera,Longdong and Algoniun,were detected,respectively,which could be used to identify alfalfa varieties through exploring the variety-specific primers.