Xanthomonas vesicatoria

Bacterial spot


Xanthomonas vesicatoria is a bacterium that causes bacterial leaf spot on peppers and tomatoes.

Life cycle and appearance of Bacterial spot

Xanthomonas vesicatoria survives on volunteer tomato plants in the field and on diseased plant debris. The bacteria are also seed-transmitted. Disease development is favoured by temperatures between 24 and 30 °C and high precipitation due to rain, fog or overhead irrigation. Infection is through stomata and wounds. The dispersal is in windblown water drops, mechanical means such as clipping and handling and aerosols. Many isolates are resistant to copper-containing pesticides.

How to prevent Bacterial spot

  • Use clean propagation material and disease-free seed
  • Remove sources of inoculum such as dead leaves
  • In field-grown tomato and pepper rotate fields to prevent infection from volunteer plants and crop debris
  • Avoid waste piles in the vicinity of the greenhouse or field
  • Resistant cultivars of pepper are available and should be used

Prevent plant diseases by optimizing plant potential and crop resilience.