Bacterial Spot

Symptoms

Small greasy dark spots on leaves that turn angular and drop their centers, and raised scabby lesions on fruit. On pepper the fruit spots are corky and disfiguring enough to reject a whole load; on tomato the same organism defoliates plants in hot wet weather.

Management

Seed and transplant hygiene first, because the pathogen rides seed and volunteers. Copper-mancozeb programs follow, though copper resistance is widespread in Xanthomonas populations. Pepper breeding has produced named race-specific resistance genes (Bs1 through Bs3), which is why commercial bell varieties list numbered race resistance while tomato varieties rarely do.