1. National Institute of Crop Science; 2-1-18 Kannondai Tsukuba Ibaraki 305-8518 Japan
2. Nagano Prefecture Vegetable Ornamental Crops Experimental Station; 1066-1 Tokoo Shiojiri Nagano 399-6461 Japan
3. National Agricultural Research Center for Kyushu Okinawa Region; 2421 Suya, Goshi Kumamoto 861-1192 Japan
4. Tokyo Japan