Genetic Diversity Analysis On Germplasms And DNA Fingerprints Construction In Azuki Bean (Vigna Angularis)

Azuki bean(Vigna angularis)originated in China, as Chinese traditional crops, it plays an important role not only in adjusting planting structure of modern agriculture but also in food export. A total of 145 germplasms, including 24 wild,24 weedy and 97 cultivated azuki bean were evaluated on genetic diversity by SSR markers. DNA fingerprints of cultivars were constructed. This research is very useful to efficiently develope and protect germplasm resources in adzuki bean.Seventy-seven high polymorphic primer pairs which 75 came from adzuki bean and 2 from mung bean were obtained through screening 196 SSR primer pairs of adzuki bean and 21 SSR primer pairs of mung bean. The polymorphic frequency was 38.3% and 9.5% respectively.20 maximal polymorphic primer pairs including 18 primer pairs of azuki bean and 2 primer pairs of mung bean from 77 high polymorphic primer pairs were selected to amplify on 145 germplasms. Rich genetic diversity was revealed in 145 germplasms, Each primer pair of SSR detected polymorphic bands ranged from 2 to 19 with an average of 8.2 bands. The mean of Polymorphism information content (PIC) was 0.6922.145 germplasms were divided into 13 groups. The three main groups are wild, weedy and cultivated azuki bean. There are landrace and commercial variety in cultivated azuki bean. The clustering results of the landraces and commercial cultivars had not obviously relative with geographical origin, while wild azuki bean were obviously relative to weedy azuki bean in geographical origin.145 germplasms were classified into four groups:the wild, weedy, landrace and commercial cultivar for genetic diversity, then cluster analysis was done. Integrated analysis on all parameters indicated that genetic diversity is wild> weedy> landrace > commercial variety; commercial cultivars had narrow genetic basis;weedy adzuki bean is closer relative to the wild than cultivated adzuki bean.According to geographical origin, landraces and commercial cultivars were classified into 14 groups for genetic diversity and cluster analysis. The results exhibited:cultivated azuki bean from Heilongjiang, Shanxi, Beijing and Japan had relatively high genetic diversity;cultivated azuki bean from Northeast China and Japan is closely genetic relationship;Shaanxi may be a important area for spreading ways and gene flow of adzuki bean.17 germplasms get themselves specific DNA fingerprint. DNA fingerprints of 47 commercial varieties were constructed.