Aflatoxins is a word often heard this time of season. As crops near maturity and temperatures remain high, this fungal problem has the ability to infect fields and stored commodity in the bin, both which can result in huge financial losses. IntelliFarms University shares information about this fungus and how to manage against it:
What are aflatoxins?
Aflatoxins are a byproduct produced by a fungus Apergillus Flavus and is most commonly found on corn, peanuts, cottonseed and their processed products. This fungus invades grain at relative humidites above 70% and temperatures above 65 degrees Fahrenheit. Aflatoxin-contaminated food can lead to liver cancer and has been linked to a higher prevalance of hepatitis B. The FDA lists the contamination level of aflatoxins for human consumption as 20 ppb (parts per billion) for corn intended for human food.
Preventing aflatoxins in the field
Stress on crops caused by excessive heat, drought, insect damage and high nighttime air temperature (above 70 degrees) can make grain susceptible to fungal disease like Aspergillus Flavus. Field management strategies can be used to prevent or reduce crop stress. For example, sensor technologies can keep you informed on real temperature and soil moisture conditions, which can help make proactive irrigation decisions. Additionally, farms could consider water stress-resistant hybrids, which better withstand drought stress and can be less vulnerable to fungal growth. Tools are available that can help you evaluate pest-resistant and drought-resistant hybrid field trials in your area.
When it comes time to harvest, take note of the areas of the field that have experienced high-degrees of stress, water or otherwise. You may want to consider harvesting these areas separately in order to not cross-contaminate any present aflatoxin-affected crop with the rest.
Managing against aflatoxins in grain storage
Achieving and maintaining safe storage conditions in the grain bin is important to prevent mold and fungal growth and activity. Applying productive air to dry and/or cool the grain to optimal moisture content (MC) and temperature is key. The normal safe storage MC depends of the equilibrium moisture content (EMC) of each particular hybrid. (IntelliFarms can work with you to determine theunique EMC of your stored grain variety.) Getting to and maintaining safe storage MC within a safe amount of time is critical when managing grain in grain bins. For example, standard corn put in the bin at 80 degrees and 20% moisture content will start deteriorating greatly after 12 days.
Dr. John Lawrence of IntelliFarms University recommends that if you know you potentially have aflatoxin-affected corn in the bin, it needs to be dried quickly to a moisture content (MC) that is 1% lower than what is considered the normal safe MC for that commodity.
Monitor the moisture and temperature of your grain the entire time it is stored. Monitoring tools are available to help you get a picture of the conditions throughout the grain bin, and automated systems control when the fans and heaters run to get grain to optimal moisture and temperature. These systems are key in helping to identify and proactively manage against pockets of wetter and warmer grain in the grain bin that left unmanaged could result in mold/fungal activity.
It's also important to handle grain carefully when moving into or around within the bin. Grain with cracks in the seed coat make it more vulnerable to insects and mold.
Contact IntelliFarms at any time to speak with one of our Grain Specialists about strategies for managing your stored commodity, and about our field management and seed selection tools.