1. Faculty of Agriculture , Kyushu University, 6-10-1 Hakozaki, Higashi-ku , Fukuoka 812-8581 , Japan
2. Faculty of Agriculture , Kyushu University , 6-10-1 Hakozaki, Higashi-ku , Fukuoka 812-8581 , Japan , Phone: +81-92-642-2988, Fax: +81-92-642-2988