Analysis of the genetic diversity of Medicago ruthenica by phenotype and SSR marker in China | 中国扁蓿豆遗传多样性的表型和SSR标记分析

Chinese. 揭示中国扁蓿豆种质资源的遗传多样性，为扁蓿豆种质资源的收集、保护及更好地利用提供参考。利用15个表型性状(株高、叶长、叶宽、荚果长、荚果宽、种子长、种子宽、千粒质量、花序花朵数、单枝花序数、花序种子数、叶型、花色、叶色和生长习性)和16对SSR标记，检测来自中国7个省（市）的44个扁蓿豆种质资源的遗传多样性。表型性状分析结果表明，15个扁蓿豆表型性状表现出较大差异；花序种子数、种子长、种子宽和单枝花序数等性状是居群间和居群内差异较大的性状，是造成表型差异的主要因素；表型聚类将44个扁蓿豆划分为8个类群，大部分材料聚在第Ⅱ类群内，但仍有部分材料独立成群。SSR标记分析结果表明，筛选出16对苜蓿SSR引物，每对引物可以稳定检测到3~10个等位基因，共扩增119条谱带，平均每个位点6个等位基因，多态性比率为80.7%，每对引物产生有效基因 96个，平均多态信息含量(PIC)为0.26；16对引物将44个扁蓿豆划分为8个类群，大部分材料主要集中在第Ⅲ类群内。Mantal测验表明，表型性状欧式遗传距离矩阵与SSR标记遗传距离矩阵之间存在极显著正相关，相关系数r=0.013 8，t=0.188 7，表明重要的表型性状能够较准确地反映亲缘相近材料的遗传变异。中国扁蓿豆种质资源的遗传多样性水平较高。

English. The study was done to reveal the on genetic diversity of Chinese Medicago ruthenica. Phenotype, SSR marker were used to analyze the genetic diversity of 44 M. ruthenica germplasms from 7 provinces in China. 15 phenotypic characters displayed significant difference. Principal component analysis indicated that number of seeds/raceme, seed length, seed width, and number of inflorescence/branch were varied significantly in various populations and populations and these 4 characters above were mainly factors which produced morphological variation. Phenotype cluster analysis showed 44 M. ruthenica germplasms were divided into eight groups, most of them were clustered into the second group, and a few of them were clustered into other groups. SSR marker showed that 16 pairs of primers were obtained. 3-10 alleles were detected in every primer, 119 bands amplified, per locus on average had 6 alleles, of which 80.7% were polymorphism. Every primer produced 96 effective genes, and the average polymorphic information content (PIC）was 0.26. Cluster analysis showed 44 M. ruthenica germplasms were divided into eight groups, and most of them still focused on the third group. Compared to morphological and SSR marker, the genetic distance matrix was significantly positive correlated, correlation coefficient r=0.013 8, t=0.188 7. There is a higher genetic diversity in M. ruthenica germplasm in China.