Fruits and Vegetables - Tomato Disease Control

Tomato Disease Control

Tomato diseases can be controlled three ways:

Using disease-resistant plants when available.
Using good cultural practices.
Using fungicides.

Good cultural practices to minimize or prevent disease include:

Remove and destroy diseased plants at the end of the season.
Use mulches such as compost, straw, grass clippings or well-rotted manure. Apply these after the soil has warmed.
Trellis tomatoes in cages 2 feet in diameter and 4-5 feet tall. Space trellised tomatoes a minimum of 24 inches apart.
Try not to grow tomatoes or their relatives in the same spot more than once every 3-4 years.
Avoid overhead watering.

Fungicides

Fungicides will control the spread of disease but will not eliminate it. Fungicides should be applied according to the product label. Products labeled for tomatoes include:
Mancozeb
Maneb tomato and vegetable fungicide
Chlorothalonil, sold under the trade names Daconil 2787, and Ortho Multi-Purpose Fungicide.

There are also organic, copper fungicides. They are most effective against bacterial diseases but control many fungal diseases. Bordeaux Mixture and Liquid Copper fungicide are two such products.

The two most common tomato diseases are Alternaria (Early blight) and Septoria Leaf Spot. Septoria Leaf Spot is evident around fruit set. Alternaria may be present during all stages. They are similar in appearance. Both cause leaf spots to form on the lowest, oldest leaves and progress upward. Infected leaves yellow, shrivel and die. Septoria leaf spots are small, numerous, dark spots that frequently have white to grey centers. Alternaria leaf spots are larger, less numerous and exhibit a target pattern, formed of rings of dried tissue.

Title:	Tomato Disease Control	Number:	478
Script writer:	Beth Jarvis	Source:	University of Minnesota Publication, Nonparasitic Disease of Tomatoes
Date:	1998/2001/2006	Reviewer:	Chad Behrendt

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