Xanthomonas

Xanthomonas is a genus of bacteria that causes a wide number of plant diseases in important crops. This can include tomatoes, brassicas, grapes, and citrus fruits. The bacteria cause spots and blights on the leaves, stems or even fruit through wounds or natural openings.

The bacteria can survive on plant debris for up to two years, even if it is decomposing in the soil. The diseases spread through contaminated seeds or infected plant material.

Important economic diseases include:

  • Citrus Canker - Leads to lesions on most citrus fruits
  • Bacterial Leaf Spot - Causes leaf spots, blight and lesions on tomatoes and peppers
  • Black Rot - Affects brassica vegetables like cabbage, broccoli, and cauliflower, characterized by V-shaped yellow lesions on leaves and blackening of the veins
  • Bacterial Fruit Spot - Affects peaches, plums, and other stone fruits, leading to spots on leaves and fruits
  • Bacterial Leaf Streak - A disease in cereals and grains

Controlling Xanthomonas

If possible, make you are transplanting or direct seeding healthy plants. A hot water treatment can be used to kill off any bacteria in or on the seed.

Disinfect pruners in between use and remove any diseased plant material from the growing site.

Products to control Xanthomonas include: