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SYMPTOMS OF FUNGAL DISEASES

When spots or lesions enlarge and merge (see arrow), so that large areas of a leaf are necrotic and diseased, then we call this a BLIGHT.

Perhaps the most familiar blights that homeowners encounter are those that occur on tomatoes. Alternaria leaf blight caused by Alternaria solani (left) and Septoria leaf blight caused by Septoria lycopersici (right) are common in home vegetable gardens, causing browning and loss of leaves from the base of the tomato plant, up.