Not All Corn Ear Mold Produces Aflatoxin

Concern over tainted grain heats up as elevators brace for the worst.

Published on: Sep 17, 2012

Word from sources inside the grain handling industry say elevators fear the aflatoxin issue is a ticking time bomb. Not that many instances have shown up yet, but many fear they will as producers go deeper into harvesting stress-damaged corn over the next few weeks.

There are still consultants and agronomists who are hoping the potential time bomb is a dud, and that the problem never materializes, at least not in widespread fashion. Charles Woloshuk, Purdue University plant pathologists, says he has found Aspergillus and the aflatoxin it produced in some fields, but it's still too early to know if it will be a big problem or not. The return to wet weather after hot, dry weather favors it. But days when it is cooler than normal slow it down. So it's difficult to tell how it might develop on un-harvested corn in the next few weeks.

As harvest continues, so do the worries about Aflatoxin.
As harvest continues, so do the worries about Aflatoxin.

There are other molds out there besides Aspergillus. Betsy Bower with Ceres Solutions, Terre Haute, Ind., says the first step is to have ears with mold tested at a university or commercial lab. At this stage you're testing for mold, not mycotoxin. She has sent in samples that actually came back with two types of mold on the same ear. Ear molds take advantage of opening of ear husks by bird feeding, loose-husks, ears protruding from husks, and holes in ears made by corn earworm or western bean cutworm. The latter is particularly nasty because it can make several holes in the same ear, with each one being a potential entry point for disease.

If you find that you have Aspergillus, the next step is to see if it is producing aflatoxin. Researchers in Illinois stress that just because you find Aspergillus ear mold (the olive gray, dusty mold) doesn't mean it is producing aflatoxin.

To detect aflatoxin, consult with a lab set up to detect mycotoxins. It may be an animal disease diagnostic lab, because the mycotoxins affect animals, or it might be a commercial lab. Some elevators are using sophisticated test strips that can be read in electronic scanners to determine parts per billion of aflatoxin on the spot.

If the crop is insured with anything but GRIP insurance, contact your insurance agent if you suspect you have moldy corn. There could be a wait for adjustors to make it to your farm in hard-hit areas where they have a backup of calls and claims to make. Plan far enough ahead before harvest to allow for the adjustor to visit the field. There still could be a time delay if you're waiting to confirm aflatoxin. Whether or not aflatoxin is present may determine whether you dry it at home in a separate bin, how far you dry it, or whether you can take it to an elevator.