1. Tokyo University of Agriculture and Technology, Saiwai, , Fuchu, Tokyo 183-8509, Japan
2. Forestry and Forest Products Research Institute, Matsunosato, Tsukuba, Ibaraki 305-8687, Japan
3. National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305, Japan
4. Department of Entomology and Nematology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA