[Midwest and Northeast states include: Delaware, Illinois, Indiana, Iowa, Maryland, Michigan, Minnesota, northern Missouri, New Jersey, New York, North Dakota Ohio, Pennsylvania, South Dakota, and Wisconsin]
Ear rots and their resulting mycotoxins are sporadically problematic from year to year across the Midwest and Corn Belt. The type and prevalence of ear rot will depend on the weather conditions at silking.
Gibberella ear rot is the most frequently observed ear rot in this region, although Fusarium ear rot can be problematic in some years. Aspergillus ear rot and aflatoxin is infrequently observed at damaging levels in this region, except in very hot and dry years.
Midwest ear rot management recommendations are as follows:
- Plant less susceptible hybrids in fields at risk for disease development. Risk factors include continuous corn fields, minimum or no-till fields, and fields with a history of ear rots.
- Promote conditions that favor plant growth and reduce plant stress.
- Fungicides are generally not recommended for ear rot and mycotoxin management.
- Fields with ear rots should be harvested early and grain dried to below 15% moisture to prevent additional mold and mycotoxin accumulation.
- Adjust the combine to discard lightweight or damaged kernels which may contain mold or mycotoxin.
- Segregate grain from moldy fields and store appropriately. Check bins periodically to make sure moisture has not increased during storage.
A note on Aspergillus ear rot management:
Atoxigenic products may be available for in-season management of aflatoxin in the Midwest, but research on the efficacy and need for these products in this region is still needed before incorporating these into Midwestern corn production systems.