Radical Leaf Variation of Wild Radish in the Sea Coast of Japan

As a basic research for the population variability in the run-wild form of cultivated radish, the radical leaves at rosette stage were examined using the experimentally raised plants of which seeds were obtained from ten natural populations in Japan. The leaves were highly variable both in shape and size. Two leaf morphs, the pinnatilobed leaf and the simple lyrate leaf, were found in the seven populations. The frequency of simple leaf morph was high in the northern populations of Japan. The leaves from the northern populations in Japan were smaller than those from the southern populations. The differentiation in leaf size among the populations and between the families was detected. Diversities in leaf size among populations and the distribution of the simple leaf morph in Japan suggest that the wild radish might be climatically adapted to given environment by receiving intensive gene flow from cultivated radish