Lettuce bacterial leaf spot

SYMPTOMS AND SIGNS
Aerly symptoms of bacterial leaf spot are small (less than 0.25 inch in diameter), water-soaked leaf spots on the older leaves of the plant. These lesions are typically bordered by leaf veins and angular in shape. Lesions quickly turn black—a diagnostic character of this disease. If disease is severe, numerous lesions may coalesce, resulting in the collapse of the leaf. Older lesions dry up and become papery in texture, but retain the black color. Lesions rarely develop on newly developing leaves.