Check current clearances of fungicides effective in controlling rust. Sulfur may be used. They are most serious during periods of prolonged moist weather and on late summer or early fall plantings. Severe leaf spotting results in defoliation with subsequent yield reductions. Plants die quickly.
Lower stem is gray with internal black flecking of tissue.
Most serious when mature plants come under moisture stress. Same as charcoal rot. See the section on charcoal rot. Infection of young pods causes curling and shedding. Spots also occur on leaves, characterized by a brownish to purple mold growth on underleaf surfaces.