苜蓿遗传多样性和亲缘关系的SSR和ISSR分析

Estimates of Genetic Diversity of Alfalfa by SSR and ISSR

在苜蓿(Medicago sativa L.)基因组SSR和ISSR分析的基础上,筛选出8对SSR引物和12个ISSR随机引物,通过PCR扩增在55个国内外苜蓿品种(品系)中获得126条多态性位点。利用SSR和ISSR标记对其DNA指纹图谱和遗传多样性进行研究。采用类平均法(UPGMA)Nei氏距离进行聚类分析,将55个苜蓿种质划分为4个大类群和7个类型,为苜蓿引种、亲本选配和种质资源评价提供依据。分子标记分析结果表明:我国苜蓿地方品种遗传基础广阔,在基因型表现特异性的同时又有较强的地域性;我国苜蓿育成品种间的遗传距离大,表现出遗传基础的异质性。

Based on the established analysis system of Simple Sequence Repeat （SSR） and Inter Simple Sequence Repeat （ISSR）for genomic DNA of alfalfa （Medicago sativa L. ）, we obtained 126 polymorphic bands by PCR amplification with screened 8 SSR primers and 12 ISSR primers from 55 domestic and overseas alfalfa cultivars. The genetic diversity of the 55 alfalfa cultivars was evaluated by SSR and ISSR fingerprinting. The UPGMA analysis of Nei＇s genetic distance clustered 55 alfalfa entries to 7 types derive from 4 groups. The SSR and ISSR markers are efficient tools for fingerprinting cultivars and for conducting genetic-diversity studies in alfalfa. The results of molecular markers assay indicated that the germplasm of Chinese domestic alfalfa have a wide genetic background, a fact certifying that its genetic difference is distinct and regional. There are wide gaps of genetic distance among Chinese released cultivars.