Abstract
Peucedanum japonicum comprises three allopatric varieties : var. japonicum, var. latifolium, and var. australe. Allozyme analysis was employed to estimate levels of genetic variation within and among populations of these varieties and to show whether the genetic differentiation is correlated with the three varieties. A UPGMA dendrogram defines three main clusters. These clusters are not concordant with the three varieties. Mean levels of expected heterozygosity showed that the Japanese mainland and the northern Ryukyus populations have low genetic variation and the central Ryukyus populations have high genetic variation. Genetic differentiation of P. japonicum may strongly reflect the geological history of the Ryukyu Islands.
