抄録
A medicinal species, Dioscorea tokoro (Dioscoreaceae), distributes in temperate eastern Asia including the entire Japan Islands. To determine the colonizing history of this species into Japan, we investigated the geographic pattern of its nucleotide sequence variations in Japan. To reveal the genetic relationships between the species, forty-five Dioscorea species were reconstructed molecular phylogenetic tree using the rbcL and matK sequences, indicating that D. tokoro is the sister to D. tenuipes. Moreover, the result of network analysis of the Adh sequences using thirty individuals of D. tokoro indicates that there are two genetic groups in Japan, suggesting that this species had independently colonized into Japan at least twice.
