Soybean Rust

DISEASE SYMPTOMS

Symptoms begin on the lower leaves of the plant as small lesions that increase in size and change from gray to tan or reddish brown on the undersides of the leaves. Tan lesions, when mature, consist of small pustules surrounded by a slightly discolored deadened area with masses of tan spores on the lower leaf surface. Reddish brown lesions have a larger reddish brown deadened area, with a limited number of pustules and few visible spores on the lower leaf surface. Once pod set begins on soybean, infection can spread rapidly to the middle and upper leaves of the plant.

Information from the Extension Disaster Education Network