Analysis of the genetic diversity in the Vigna minima complex and related species in East Asia

The genetic variation in East Asian species of the genus Vigna subgenus Cer atotropis (V. angularis, V. minima, V. nakashimae, V. reflexo-pilosa, V. ri ukiuensis and V. umbellata) was investigated using AFLP methodology. Specie s in the V. minima complex, V. minima, V. nakashimae and V. riukiuensis, ha d greater intra-specific polymorphism than the other species analyzed. Vign a species from East Asia analysed could be clearly distinguished. The relat ionship between species was consistent using different analyses and showed V. riukiuensis and V. nakashimae are closely related. The phenetic distance between species (1-Jaccard's similarity coefficient) ranged from 0.279 bet ween V. riukiuensis and V. nakashimae to 0.688 between V. reflexo-pilosa an d V. minima. Genetic distance based on inferred nucleotide diversity (pi) r anged from 0.012 between V. riukiuensis and V. nakashimae and 0.053 between both V. riukiuensis and V. nakashimae and V. reflexo-pilosa. The diversity (Ha) within species, based on Shannon's information index of phenotypic di versity, was lowest in V. reflexo-pilosa (0.006) and highest in V. minima ( 0.095). Korean and Japanese populations of V. nakashimae had distinct polym orphism. Vigna riukiuensis populations from Miyako island were genetically different from populations of other islands of southern Okinawa.