Bacterial Canker of Tomato

Symptoms

Marginal leaf scorch with a yellow border ('firing'), wilting of leaflets on one side, stem cankers that split open, and the diagnostic bird's-eye spots on fruit, small white halos with raised brown centers. Systemic infections from seed can destroy transplant houses and whole fields.

Management

A clean-seed disease through and through: hot-water or acid seed treatment, certified tested lots, and strict transplant-house sanitation are the controls, because no resistant varieties exist and copper sprays only slow surface spread. The second guide in the seed industry's commercial grower disease series, alongside bacterial fruit blotch, for exactly this reason.