Abstract
Cercospora leaf spot of Sugar Beet is one of important diseases in Hokkaido. Analitical studies on its occurrence at 3 locations in twenty-five years from 1970 to 1995 were carried out. The sequence of the disease varied with year and location. The degrees of disease incidence in recent 5 years were generally low. The correlation between disease incidence and temperature was not significantly observed. However, the influence of humidity was suggested. The fungicides dramatically changed in kind. The new fungicides belonging to DMI showed the excellent protective ability.
