Abstract
In August 2001, wilted soybeans were observed in a rotational upland field in Shinshinotsu village, Hokkaido. The crowns and roots of the wilted plants were brown and decaying. Perithecia, which were reddish brown and about 0.5 mm in diameter, were observed in great numbers on the surface of the crowns. We isolated and identified pathogenic fungi from the wilted plant specimens, and examined their pathogenicity to soybean. From the results of this study, we clarified that the disease of the wilted soybean was root necrosis caused by Calonectria ilicicola. This is the first report of this disease in Hokkaido.
