Tomato: Anthracnose
Photo by: R.S. Byther
Biology
Tomato anthracnose is a fungal disease primarily seen on ripe fruit. It may sometimes affect leaves. Leaf symptoms are most common on older leaves, which show small, dark spots surrounded by a yellow halo. Fruits may be infected while green, but symptoms are seen on ripe fruit. Infected fruits initially show circular, sunken, water-soaked spots. The spots enlarge to about 1⁄2″ in diameter and become darker. They often show concentric ring markings around a tan center. Dark specks may be present on the tan area. During damp weather, masses of salmon-colored spores may develop on the surface of the lesion. The fungus frequently overwinters on diseased plant debris and can also infect other crop and weed species. Wet soils favor disease development.
Management Options
See "Using Integrated Pest Management (IPM) in the Landscape" for successful problem management techniques.
Non-chemical Management
Select non-chemical management options as your first choice!
- Plant in well-drained soils.
- Avoid overhead irrigation.
- Rotate crops on a three- to four-year cycle to avoid fungus surviving in the soil. Do not plant tomatoes in the same location each year.
- Remove plant debris from the garden. Destroy or discard (do not compost) diseased plant materials.
- Control weeds in and around the garden.
Chemical Management
IMPORTANT: Always read and follow label directions when working with pesticides.
For more information on using pesticides visit :
- Apply abonideccording to label directions
Approved Pesticides
If you choose to use a pesticide, some examples of products that are legal in Washington are listed below. Some products are labeled for just INDOOR or just OUTDOOR use, or may allow both uses. Be sure to choose a product appropriate for your situation. Always read and follow all label directions.
WSU Extension programs and employment are available to all without discrimination.
Evidence of noncompliance may be reported through your local Extension office.