Estimates of Genetic Diversity of Alfalfa by SSR and ISSR

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 con-ducting genetic-diversity studies in alfalfa.The results of molecular markers assay indicated that the germ-plasm of Chinese domestic alfalfa have a wide genetic background,a fact certifying that its genetic diffe-rence is distinct and regional.There are wide gaps of genetic distance among Chinese released cultivars.