Blemishes and quality matter. Also, weather influences disease, and you can't control the weather. Planting resistant varieties is at the top of Dainello's list of IPM practices for small farms, followed by crop rotation, scheduled planting, cultivation, sanitation, and intercropping. He also advocated the planting of trap crops, the use of protective barriers, and sticky traps to assist in the control of pests. Crop rotation is a major factor for reducing organism buildup in the soil.
Crop rotation enhances the productivity of a field and reduces the incidence of soil borne disease.
The Extension vegetable specialist said the idea is to rotate crops in a pattern according to their level of resistance to a particular soil borne disease. For example, onion, garlic, leek, shallot, and sweet corn have root knot nematode resistance. According to Dainello, the most desirable varieties should be high yielding, disease resistant, high quality, and early maturing, to reduce inputs and sprays. By selecting the right variety, you reduce the need for fungicide. Dainello said getting the crop off to a good start goes a long way towards combating other problems.