Bacterial Spot on tomato
Photo: Dr. Scot C. Nelson, CTAHR
Tomato fruit has many small spots. The leaves have dark brown or black, water soaked spots which eventually deteriorate, leaving holes in the leaves.
Spots start out as dark, raised specks that develop into scabs. Leaves have brown, irregular lesions. Bacterial spot does not affect the taste of fruit.
Bacterial Spot on tomato
Photo: Dr. Wayne Nishijima
You should destroy plants after harvest to prevent the spread of bacterial spot. Good sanitation helps; keep weeds under control and remove plant debris. Rotate crops so that you are not planting tomatoes in the same area season after season, and if you buy seedlings, be sure that they are disease free before transplanting.
Chemical Control: Copper sprays are somewhat effective. Read and follow the instructions on the label.
Kendal Lyon, Hawaii Island Master Gardeners