1. Department of Regional Strategy, Hokkaido Agricultural Research Center (HARC), National Agricultural and Food Research Organization (NARO), Sapporo, Japan
2. Division of Crop Production Systems, Central Region Agricultural Research Center (CARC), NARO, Tsukuba, Japan
3. Division of Plant Disease Management, CARC, NARO, Tsukuba, Japan
4. Division of Farming System Research, HARC, NARO, Memuro, Japan