Corn Diseases and Mycotoxin Contamination of Corn Grain in Southwest New York
Joshua Putman, Field Crops and Forage Specialist
Southwest New York Dairy, Livestock and Field Crops Program

Mycotoxin is a general term for a poison produced by a fungus and can be toxic when inhaled, absorbed through the skin, or consumed at very low concentration levels. Corn and small grain cereals are especially prone to mycotoxin accumulation in their seed tissue. In the past, it was believed that the fungus affected grain only during the postharvest stage, particularly when grain was stored under suboptimal conditions (hot and humid/moist). Although these factors can promote fungal growth in storage, this occurs during the growing season as well. In the field, mycotoxin outbreaks are seasonal, and will occur under favorable weather conditions for disease development. Bird and insect damage can also increase the risk for mycotoxin contamination. In addition to mycotoxin contamination of grain crops, mycotoxigenic fungi cause ear rots and stalk rots in corn. Some corn fields in SWNY are beginning to lodge due to stalk rots. Photos were sent to Dr. Gary Bergstrom, Field Crops Plant Pathologist at Cornell University, and it was confirmed that we are experiencing stalk rot damage in corn fields throughout the state. "It is believed that drought stress was a likely contributor this year," says Bergstrom. To help reduce the risk of late-season corn disease and mycotoxin accumulation, here are a few practices to consider: plant locally adapted corn hybrids, avoid corn-after-corn rotations, apply appropriate amounts of fertilizer, and plan ahead. An article written by Dr. Bergstrom, provides detailed information about mycotoxins of corn in the Northeast. Contact Josh Putman if you are experiencing lodged corn.
Upcoming Events
Fecal Egg Count Mobile Workshop - East Aurora
October 21, 2025 : Fecal Egg Count Mobile Workshop - East Aurora
East Aurora, NY
This workshop will explain why regularly testing fecal egg counts can help you with understanding your animals' parasite loads and dewormer resistance. Attendees have the opportunity to prepare and evaluate fresh fecal samples under the microscope and practice interpretations.
Fecal Egg Count Mobile Workshop - Jamestown
October 30, 2025 : Fecal Egg Count Mobile Workshop - Jamestown
Jamestown, NY
This workshop will explain why regularly testing fecal egg counts can help you with understanding your animals' parasite loads and dewormer resistance. Attendees have the opportunity to prepare and evaluate fresh fecal samples under the microscope and practice interpretations.
2025 Annual Cornell Sheep and Goat Symposium Day 1
October 31, 2025 : 2025 Annual Cornell Sheep and Goat Symposium Day 1
Join sheep and goat production experts for three days of informational lectures, hands-on experiences, and demonstrations around sheep and goat production and management. The symposium starts on Friday, October 31 and runs through Sunday, November 2, 2025.
Announcements
Herbicide Resistance Screening
We are screening weed species for herbicide resistance.Species we are looking for include, but aren't limited to:
- Tall Waterhemp
- Palmer Amaranth
- Marestail
- Redroot Pigweed
- Foxtails
- Common Lambsquarters
- Common Ragweed
Reach out to Katelyn Miller at 716-640-2047 or km753@cornell.edu for more information.