The objective of harvesting early is to reduce fungal exposure to warm, humid conditions during dry down by artificially drying the corn. Wet grain not quickly dried during warm conditions, however, begins heating up to intolerable levels quickly due to excessive grain respiration. These conditions provide an ideal environment for fungal growth and simultaneous aflatoxin buildup. Do not store wet grain in trucks, combines, bins, or any nonaerated site more than 4 to 6 hours before beginning drying. Producers must be extremely cautious about using bins designed for handling rice or other low-moisture grain to dry corn.
Fungal infection is likely in shriveled, cracked kernels and foreign material.
Thus, contamination sources may be eliminated by properly adjusting the combine for minimal kernel damage and maximum cleaning or running the grain through a mechanical cleaner. Foreign material present in a grain sample will also enhance mold growth in storage. Spores from fungi on infected grain readily disperse during handling and contaminate unaffected grain. On a daily basis, remove corn and debris remaining in combines, trucks, carts, pits, augers, bins, and elevators. Insects and rodents are other potential contamination sources.