Affiliation: | Kihara Institute for Biological Research, Yokohama City University, Maioka, Totsuka-ku, Yokohama 244, Japan,; Institute of Radiation Breeding, NIAR, MAFF, Ohmiyamachi, Naka-gun, Ibaraki 319-22, Japan, and; Faculty of Horticulture, Chiba University, Matsudo, Chiba 271, Japan |