The damage later develops in a constriction that with more wind eventually breaks off. This problem has been accentuated by the heavy rains and then the severe drying. There is a lot of concern about what is going to happen to our corn this season, especially the late planted corn. If the current dry and hot weather continues, we may catch up on heat units, but there is a considerable possibility that we will encounter more diseases this season than we normally see. The long, wet, cool soil temperature will have given various soilborne fungi an opportunity to infect the seedlings.
Stalk rot diseases are a major threat.
Research done by our group at Fort Collins has shown that the fungi are always present and frequently infect the plants. But if little or no stress develops from other sources, i.e., compaction, water logging, high plant populations, mite damage etc., the crop can usually tolerate it and not experience significant losses. With the cool and wet soils, there is a need to till and open up the soil for aeration and promotion of root growth. The delayed planting exposes the developing corn seedlings to the vector of the virus-like causal agent. Corn plants will not be as well developed as they normally are when the wheat starts to mature and the wheat curl mites begin to leave them.