Hybrids should be selected for resistance or tolerance to stalk rots, foliar diseases and ear rots, particularly those that have occurred locally. Seed dealers should provide information on hybrid reactions to specific diseases in Ohio (Table 4-21). See the section on Disease Management for more on the use of hybrid resistance and tolerance to minimize crop losses.
Hybrid response to high population can be limited by stalk lodging, which often increases at higher plant density. Some hybrids that have shown positive yield response to higher populations cannot be grown at high plant densities because of the increased risk of lodging at harvest. Lodging reduces yields and slows the harvest operation. Therefore, it is essential that hybrids planted at high seeing rates possess superior stalk quality for standability. Hybrids should also have resistance (or the best levels of tolerance available) to fungal leaf diseases (such as gray leaf spot and northern corn leaf blight), which contribute to stalk lodging problems and stalk rots (such as Anthracnose and Gibberella).