Bacterial Spot

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BACTERIUM: Xanthomonas campestris pv. vesicatoria

INFECTS : foliar plant parts and fruit.

SYMPTOMS : foliar lesions are small (1/8 in) and dark brown, fruit spots are 1/8 in - 1/4 in. in diameter, raised, with a ruptured epidermis. Round to angular leaf lesions are typically brown with a chlorotic ring.

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PATHOGEN SPREAD : bacterium can be seedborne, transplant-borne or spread from volunteer tomatoes or crop debris by wind-driven rain into stomates of foliage or wounds or insect punctures or fruit. It can also be spread mechanically.

FAVORABLE CONDITIONS : wet, windy weather with relatively high temperatures of about 80-89 F. Can be very severe in late summer, early fall.