基于SCoT标记分析紫花苜蓿遗传多样性的取样数量  

Optimizing Sample Size for Assessing the Genetic Diversity in Alfalfa(Medicago sativa)Based on Start Codon Targeted(SCoT)Markers

作　　者：毛培 申书恒 蒲军 娄可可 周强[1] 王增裕 孙娟[2] 刘志鹏[1] MAO Pei;SHEN Shu-heng;PU Jun;LOU Ke-ke;ZHOU Qiang;WANG Zeng-yu;SUN Juan;LIU Zhi-peng(State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, Gansu Province 730020, China;Grassland Agri-Husbandry Research Center, College of Grassland Science, Qingdao Agricultural University, Qingdao, Shandong Province 266109, China)

机构地区：[1]兰州大学草地农业科技学院,兰州大学草地农业生态系统国家重点实验室,甘肃兰州730020 [2]青岛农业大学草业学院,草地农牧业研究中心,山东青岛266109

出　　处：《草地学报》2022年第5期1110-1121,共12页Acta Agrestia Sinica

基　　金：国家自然科学基金项目(31672476和32071862);甘肃省重大专项(19ZD2 NA002)资助。

摘　　要：本研究采用目标起始密码子多态性(Start codon targeted,SCoT)标记,对600份不同紫花苜蓿(Medicago sativa L.)材料(共6个种质)的基因组DNA进行扩增,分析了不同取样数量下(10,15,20,30,40,50,60,70,80,90和100)紫花苜蓿的遗传多样性,旨在筛选出代表紫花苜蓿种群遗传多样性的最佳取样单株数。结果发现,6条SCoT引物共扩增出80个条带,平均每条引物的扩增条带数为13.3个,多态性条带百分率为100%。在评价不同取样梯度下的紫花苜蓿遗传多样性覆盖度时发现,当取样数量增加至40时,6个供试紫花苜蓿种质的遗传多样性覆盖率均达到95%以上。此外,本试验采用UPGMA与STRUCTURE聚类分析方法,分析了不同取样梯度下紫花苜蓿的遗传结构。结果表明,样本量为40时能够有效反映紫花苜蓿群体间差异。Alfalfa(Medicago sativa L.)is one of the most economically valuable forage crops in the world.Due to its autotetraploidy and cross-pollination with a complex genome structure,genetic and breeding projects for alfalfa improvement have been significantly hindered.In the present study,six different germplasms of alfalfa including 600 individuals were used for sample size determination.The analysis of genetic diversity of alfalfa was performed with start codon targeted(SCoT)markers.From the PCR amplification,we selected 6 out of 56 primers that were used in previous studies.All analyzed markers were polymorphic,and 80 bands were identified,with 13.3 bands per locus detected.The percentage of polymorphic bands values were all 100%,which indicated that the markers were highly informative.The genetic diversity of alfalfa with 11 random sampling levels(10,15,20,30,40,50,60,70,80,90,and 100 genotypes)was compared in this study.When the sample size was increased to 40,there was a coverage of at least 95%genetic variation in the six germplasms.Additionally,based on the unweighted pair-group method with arithmetic averages(UPGMA)and STRUCTURE analysis,each cultivar in this study could be distinguished from others by utilizing a sample size of 40 individuals.The results of the present study showed that these SCoT markers would benefit the alfalfa research community for genetics and breeding.Furthermore,this study also established the foundation for future cultivar identification,resequencing and evolution in the alfalfa.

关 键 词：紫花苜蓿 SCoT标记 遗传多样性 取样数量 

分 类 号：S963.223.3[农业科学—水产养殖]