1. Tama Forest Science Garden, Forestry and Forest Products Research Institute, National Research and Development Agency, Todori 1833-81, Hachioji, Tokyo 193-0843, Japan;, Email: katsuki@ffpri.affrc.go.jp
2. NARO Institute of Fruit Tree Science, National Agriculture and Food Research Organization, 2-1 Fujimoto, Tsukuba, Ibaraki 305-8605, Japan, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan