Abstract: RAPD variation was assessed in 163 accessions of adzuki bean from China, Japan, Korea, Bhutan, Nepal and Vietnam. 285 bands, including 261 polymorphic bands, were detected by 27 RAPD primers. Among those bands observed in wild, weedy and cultivated adzuki bean, the rates of polymorphism were 85.82%, 80.46% and 83.52%, respectively. There were species-specific bands in the three races. The order of genetic dispersion was: wild adzuki bean＞weedy adzuki bean＞cultivated adzuki bean, and the order of Gst was: wild adzuki bean＜weedy adzuki bean＜cultivated adzuki bean. The weedy adzuki bean has close genetic relationship with wild adzuki bean assessed by the difference of genetic dispersion. From the average of genetic similarity coefficient, a relative close genetic relationship was observed in the weedy adzuki bean, whereas the wild and cultivated adzuki bean, as two pole of evolution, has high genetic variation. The material from Southwest China and South Japan has relatively high genetic dispersion, low Gst and average of genetic similarity coefficient. The cluster analysis showed that eight groups can be clustered when genetic similarity coefficient was given as 0.32. It appears that the cluster has obviously associated with the genetic races and different adzuki bean geographical regions.

Key words: Adzuki bszean or Adzuki bean (Vigna angularis), Germplasm resources, RAPD(random amplified polymorphic DNA), Genetic diversity, Genetic evolution