March 1994 Integrated Crop Management is published by the Department of Entomology , Iowa State University , Ames, Iowa. Before starting up the combine, you should think about the possibility of ear rot and kernel rot diseases in your corn. Detecting these diseases before harvest is a good way to avoid problems and make proper decisions before it is too late. Some of these fungi can produce mycotoxins that are harmful to livestock, so it can pay to be aware of their occurrence in your fields. To check for ear rots, strip back the husks on at least 100 plants scattered throughout the field.
Scout fields separately according to hybrid, tillage and rotation history, and planting date.
It is important to be able to recognize the ear rot diseases because their potential impact is very dependent on the particular fungus involved. Fortunately, conditions have not been especially favorable for ear rot diseases this year. Although it has been cool, most of the state did not experience very wet conditions during the second half of the season, so the occurrence of Gibberella and Diplodia ear rots probably will not be extensive. On the other hand, it has not been hot enough for Aspergillus to become a problem. When evaluating an ear rot problem, remember, certain ear rots are a warning sign to suspect toxins, but ear rots do not always lead to toxin problems.