1. International Center for Research and Education in Agriculture, Nagoya University, Nagoya, Japan
2. Hokkaido Agricultural Research Center, National Agriculture and Food Research Organization, Sapporo, Japan
3. Applied Social System Institute of Asia, Nagoya University, Nagoya, Japan
4. Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Japan
5. Industrial Crops Research Institute, Kenya Agricultural and Livestock Research Organization, Mwea, Kenya
6. Department of Horticulture, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
7. Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan