The distribution and prevalence of stalk rot diseases vary from year to year. However, the diseases are present in most years even though it may be at low levels. The majority of stalk rot damage in Ontario is caused by three fungi, Anthracnose, Gibberella and Fusarium. However, Diplodia and Pythium have also been observed.
Although these fungi cause different symptoms, their ultimate effect on the corn plant is the same. They reduce grain fill, stalk integrity, and accelerate senescence. The severity of this damage increases when the crop is under stress.