Common Corn Rust occurs every growing season, giving this disease its appropriate name
In late June, symptoms caused by the fungus Puccinia sorghi begin to appear. Although the first symptoms are chlorotic flecks, they will quickly develop into chalky/dusty, brick-red pustules. Aging pustules, the color of the spores turns from brick-red to black. Pustules will continue to erupt.
Pustules are oval or elongated, about 1/8 inch long, and scattered sparsely or clustered together. The leaf tissue around the pustules may become yellow or die, leaving lesions of dead tissue.
Entire leaves can die if the damage is severe enough. Not only are leaves affected but husks, leaf sheaths, and stalks may also be infected.
Although hybrid corn is rarely bothered, foliar fungicides are available for common rust as well as inbred corn.
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