Prolonged stress weakens the immune system, opening the door for a variety of ailments that an otherwise healthy plant could overcome. During the rainfall-short 1998 growing season, some South Plains corn growers saw common smut and aflatoxin appear in their crops. Many are wondering how they can avoid a subsequent infection of these fungi this year. When we catch enough rainfall, these fungal pathogens won't do much damage. Smut is a fungal pathogen that turns corn kernels and occasionally entire ears into a swollen mass of grayish-black, powdery fungal spores.
Common smut is an airborne pathogen.
Only in severe cases will it destroy an entire ear. Common smut also can infect plants through wounds on the stalk and leaves. Head smut, on the other hand, is a soil-borne pathogen. Drought stress also favors another soil-borne fungal pathogen called aflatoxin. The results will dictate how the grain can be sold and used, according to U.S. Food and Drug Administration standards.