Pseudomonas syringae pv. tomato
Bacterial speck is widely distributed. Symptoms may appear on any plant part. Leaves of infected plants are covered by small, dark brown, irregular patches of necrotic tissue that are surrounded by yellow halos. Disease severity is increased by leaf wetness from sprinkler irrigation, rain, or heavy dews.
Minimize wetting of the leaves by using drip or furrow irrigation. Copper sprays provide effective control.