2010 Ohio Vegetable Production Guide: Disease Control
For a vegetable plant to become diseased, several conditions must be present: a susceptible host plant, a pathogenic organism, a method of distributing the organism and the proper environment for the organism to exist, enter the plant and thrive. When all these conditions are met at the same time, infection can occur, and a disease agent can become established.
The choice of disease-control measures must be based on accurate knowledge of the pathogen, its life cycle and the time of infection, as well as the part of the plant involved, the method of agent distribution and certain economic considerations. Effective control methods include:
- Resistance: Many vegetable varieties are resistant to certain diseases. Use them whenever possible.
- Avoidance: Avoid introducing plant pathogens into the field. Use certified, disease-free seeds and transplants. Do not transport soils or tools from diseased areas to disease-free areas. Rotate crops to disease-free fields to avoid buildup of pathogens in the field.
- Eradication: The removal or plow down of diseased plants from the field, if practical, can help prevent the spread of some diseases to healthy plants.
- Sanitation: Removal or plow down of old plant parts, weeds and trash is important to eliminate inoculum for the spread of the disease and new places for its development.
- Pesticides: Approved disease-control pesticides should be applied, following label directions, for specific diseases. Applications should be directed at the plant parts attacked and must be applied at the proper time.
- Insect and weed control: Many disease organisms persist in weed hosts or are spread by insects. Effective control of these pests also is an important part of a good disease control program.
- In order to initiate timely disease-control practices, crops should be routinely inspected for developing diseases.
- Growers should consider using integrated pest management (IPM) systems where available.