ARAgriculture Home Downy Mildew Downy mildew, caused by the fungus Sclerophthora macrospora, frequently occurs in areas of fields subject to flooding.
Symptoms appear in the spring as stunted yellow plants.
Severely stunted plants have many tiny stems and usually die before heading. Leaves of infected plants feel thick and leathery. Less severely infected plants may elongate and produce distorted heads with no grain. The pathogen attacks wheat, oats, barley, rice, corn, sorghum and about 140 species of wild grasses. All adapted wheats are believed to be susceptible.