1. Faculty of Agriculture; Univ. of the Ryukyus; Senbaru 1 Nishihara Okinawa 903-0213 Japan
2. United Graduate School of Agricultural Science; Kagoshima Univ; Korimoto 1-21-24 Kagoshima 890-0065 Japan
3. Regional Agricultural System Section; Okinawa Prefectural Agricultural Research Center; 820 Makabe Itoman Okinawa 901-0336 Japan
4. Product Development Div; Mitsui Sugar Co. Ltd; Nihonbashi, 36-2 Hakozaki-Cho Tokyo 103-8423 Japan