Michelle Grabowski, UMN Extension Educator
Bacterial Spot, caused by the bacteria Xanthomonas campestris pv. vesicatoria, has been found in several areas of Minnesota. This bacterial pathogen causes dark brown to black leaf spots with a pale yellow halo around them. Often the leaf spots dry up and crack, resulting in tiny holes at the center of the spot. Probably the most noticeable symptom of bacterial leaf spot of tomato, are the raised brown or black corky spots on fruit. These spots range in size from the diameter of a pencil tip to the diameter of a pencil eraser. Fruit spots can be seen on both green and ripe tomatoes. The spots are superficial and do not rot the fruit. Therefore the tomatoes can still be eaten, although they may be difficult to peel if you plan to use them in your next batch of spaghetti sauce. To learn more about managing bacterial spot of tomato read 'What are those spots on my tomato?'.