Geographical distribution of ribosomal DNA variation in taro, Colocasia esculenta (L.) Schott, in eastern Asia

Restriction fragment length polymorphism (RFLP) at the ribosomal RNA gene loci (rDNA) was investigated in 227 accessions of taro, Colocasia esculenta (L.) Schott, from China, Japan, Taiwan, and Vietnam. Eighteen different restriction fragment patterns of rDNA were observed. The results were largely consistent with a previous classification based on isozyme data. Some rDNA patterns were distributed extensively in the temperate zone from inland China to Japan. On the other hand, some other patterns ranged in coastal and/or insular areas from the tropical zone to the temperate zone (Japan). These geographical distributions may suggest two different routes for the introduction of taro into Japan: one from China,and the other most likely from Southeast Asia, via Taiwan and the Ryukyu Islands (southern Japan). This revised version was published online in August 2006 with corrections to the Cover Date.