Xanthomonas axonopodis pv. glycines
Bacterial pustule is a very common and widespread foliar disease of minor concern to NY growers, and may be found most years in many fields when conditions are favorable. Foliar symptoms are similar to those of bacterial blight and brown spot. Symptoms initiate as small yellowish spots which may have raised centers on the top or bottom of the leaf which may or may not develop into pustules. Lesion size is variable, and they may coalesce to form large necrotic areas, which causes the leaves to have a ragged appearance, and may result in premature defoliation. The bacterium overwinters on crop residues, in seeds, and in the soil where it is splash dispersed to subsequent crops.
Bacterial pustule outbreaks in NY rarely reach epidemic proportions, and have little effect on yield and require no management.
Foliar fungicides are not effective against this bacterial disease.