Goss’s Wilt in Corn
While Goss’s Wilt is found in Western Canada, and while it is not currently widespread and is hard to find in fields year after year, you do need to know how to identify and manage. Yield losses from Goss’s Wilt in corn can be significant with a potential loss upwards of 30-50% if the infection is severe enough and depending on the growth stage the plant is at when disease sets in.
Goss’s Wilt is a bacterial disease that infects corn through an opening or wound in the leaves. These wounds could be caused by hail, wind, insect pressure or another pest. When Goss’s Wilt bacterial are present, it is spread from plant to plant by the movement of water. Wet, warm weather favours the spread of the disease and temperatures about 26C are ideal.
The disease occurs in two phases: Leaf blight and systemic wilt. Goss’s Wilt can be identified by the irregular, water soaked tan lesions as well as a shiny bacterial ooze present on the surface of the leaf.
The bacterium carries over year to year in the residue, so crop rotation is very important for managing the disease. Removing or burying residue through tillage can also aid in reducing infection risk. Because Goss’s Wilt is a bacterial disease, fungicide applications will not slow the spread or cure the disease, and the best management practice is hybrid selection. Planting a hybrid with a high tolerance for the disease reduces the risk and potential loss.