Screening SSR Marker for Adsuki Bean and Its Application in Diversity Evaluation in Chinese Adzuki Bean Germplasm Resources

In the purpose of evaluating the genetic diversity of Chinese adzuki bean [Vigna angularis (Willd) Ohwi & Ohashi] germplasm with molecular markers, 106 pairs of simple sequence repeat (SSR) primers from azuki bean and its relative species were evaluated with 12 accessions of adzuki bean, and 13 pairs of primers showed polymorphism. Using these polymorphic primers, 375 adzuki bean accessions from the national core collection were analyzed. In the 366 accessions originated from China, there were 4 to 9 alleles per locus with an average of 10.2 alleles, and the mean of polymorphism information content (PIC) and percentage of polymorphic loci (PP) were 0.561 and 93.52%, respectively. The dendrogram based on unweighted pair-group method with arithmetic mean (UPGMA) showed that accession cluster correlated with their geographic origins, and the accessions from northeastern China had a close genetic relationship with those from the middle-south of China. The largest PIC went to Hubei (0.687), Shaanxi (0.640), and Anhui (0.621) provinces, which almost located in the central part of 3-dimension of principal coordinate analysis. Therefore, Hubei, Shaanxi, and Anhui provinces are inferred as the possible origin or diversity center of cultivated adzuki bean in China.