Corn Disease Update

Posted January 9, 2019

SOURCE: NE CropWatch

Below are the leaf diseases that were commonly found in 2018 Nebraska corn and ways to avoid them according to NE CropWatch.

1. Bacterial Leaf Streak- This was seen in 2018 in seedling corn crops last June. This disease is a different species of bacteria depending on if it is wheat or corn.

Ways to avoid: Rotate your crops to a non-host crop and tillage

2. Gray Leaf Spot- This was seen in corn plant samples in late June after warm and wet conditions. This disease is hard to distinguish between Bacterial Leaf streak.

Ways to avoid: Choose hybrid plants that are resistant to the disease. Rotate your crops and tillage to reduce infested crop debris from prior seasons. Use Foliar fungicides that are labeled to prevent the disease, preferably before the plant’s upper leaves have been majorly effected by the disease.

3. Southern Rust- This appeared on samples from Southeast and south central Nebraska in mid July. The disease does not survive through the winter and it comes to the crops through the wind from the south. This disease needs moisture and warm temperatures of upper 70s to lower 80s F, to take into effect.

Ways to avoid: Use hybrids that are resistant to the disease.  Also, use Foliar fungicides that are labeled to prevent the disease before the disease has developed more.

4. Stalk Rot- This disease appeared after times of heavy rainfall last summer. These diseases were found in several forms in Nebraska corn crop samples. These diseases make corn stalks weak resulting in stalk lodging, breakage, and problems with harvest for producers. They can also affect yield from killing corn plants early. Different types of stalk rot seen in 2018 were Anthracnose stalk rot, Charcoal rot,  Fusarium stalk rot and Gibberella stalk rot.

Ways to avoid: Use resistant hyprids if available depending on which stalk rot disease you are dealing with.  Choose resistant hybrids to foliage diseases. Choose hybrids with strong stalks to avoid lodging. 

Read more about stalk rot management options and crop diseases with the link below.
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