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 leaf diseases appearing in 2002

During the past week, leaf diseases have become noticeable on corn scattered throughout the state. Field specialists from several areas reported anthracnose is common. In addition, I have seen eyespot and common rust in central and southeastern Iowa. Gray leaf spot is showing up in some inbreds in our research plots in eastern Iowa