Corn ear molds and mycotoxins

There has been elevated concern this year about mycotoxins in grain, especially aflatoxins. Aflatoxins are not a common problem in Iowa, but the dry weather that occurred in some parts of the state caused stress on the plants, which lead to aflatoxin problems. Corn plants that experience drought stress are more susceptible than usual to the fungus that produces aflatoxins, Aspergillus flavus. Surrounding states also have been reporting aflatoxins in corn. In Iowa the reports seem to be limited to the southwestern corner of the state. Corn in the earliest harvested fields seemed to be the most problematic, because these fields suffered the worst drought stress. As corn harvest has progressed, reports have died down considerably, and a record-high yield in Iowa seems probable

Corn seedling diseases causing problems

As producers squeezed in their corn planting between storms this spring, corn seeds experienced very wet conditions in many cases, and emergence problems are being reported widely by extension field specialists and seed company agronomists. The Plant Disease Clinic also has received several samples of corn seedlings with disease problems. The stand problems are generally worse in the southern part of the state, except in local areas where heavy rain washed out fields or caused flooding. Iowa Agricultural Statistics reported on June 1 that 6 percent of the corn acreage will be replanted due to disease, flooding, or crusting and I expect this number will ultimately be even higher