General Management Options for Bacterial Diseases of Tomato – Vegetable Crops Hotline

General Management Options for Bacterial Diseases of Tomato

This is the fourth article in a series that describes the three primary bacterial diseases of tomato: bacterial canker, bacterial speck and bacterial spot. This article is a general summary of management options for these diseases.

All three of these diseases may be seed borne and brought into to field situation on transplants. It is important for all three diseases to purchase seed that has been tested for seed borne disease. Inspect seedlings during production or at delivery. In addition, it is possible to heat or chlorine treat seed to reduce contamination. See citation below.

  • Hot water and chlorine treatment of vegetable seeds to eradicate bacterial plant pathogens [Online]. S. A. Miller and M. L. Ivey, 2005. Ohio State University Extension Bulletin HYG-3085-05. Available at: (verified 4 April 2011)
  • Gatch, E. 2016. Organic seed treatments and coatings [Online]. eOrganic Community of Practice. eXtension Foundation. Available at:

Management of tomato seedlings in transplant facilities is critical for the future health of the crop.  Below are some recommendations for transplant production.

  • Treat seedlings in the greenhouse starting at about the first true leaf stage and at 5 to 7-day intervals. Use a combination of copper and mancozeb. Streptomycin products such as Firewall® or Harbour® may be used starting at the 2-leaf stage. Do not apply streptomycin products in the field.
    • Peroxide products such as Oxidate® may be used in addition to the ones mentioned above. Be careful with mixing the Oxidate® with other products. For example, if you mix copper and Oxidate®, mix Oxidate® at 0.33%. If you apply Oxidate® alone, use 1.0%. Oxidate® has no residue. Therefore, it is best to apply this product frequently. Do not substitute Oxidate® for copper or any other product.
    • I have thoughts on how to apply products by hand. I favor a backpack sprayer rather than a garden sprayer. See this video about the use of backpack vs garden sprayers.
  • If you grow different varieties, separate them in the greenhouse so that there is no splash between varieties. If you have different lot numbers of the same variety, also separate these.
  • Scout the plants for symptoms. If tomato transplants are purchased, inspect plants upon delivery.

Finally, in order to control any of these diseases, it is important to know which disease is in one’s field or greenhouse. Or if the symptoms are from a disease. Therefore, it is important to have the disease one is observing officially diagnosed. The Plant and Pest Diagnostic Laboratory is an excellent resource for diagnosis of plant diseases and more, see this link



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