Solar Heating (Solarization) of Soil for Control of Soilborne Pests

Soilborne pathogens cause heavy losses to most agricultural crops. Re­ peated plantings of a crop in the same plot of land, which is usual with valuable and successful crops, sooner or later results in a high inoculum buildup, forcing the farmer to change either the crop or the land. Thus, effective control of soilborne pathogens increases not only yield and quality, but available lands too, by prolonging their use for crop production. Patho­ gen control is often hampered by the fact that both the inocula of the pathogens and the lethal agents applied to the soil are affected by the soil's physical, chemical, and biological environment. However, the persistence of these organisms in the soil may serve as a clue for controlling them by interrupting their life cycle. In Israel, extension workers and growers suggested that the intensive heating that occurs in mulched soil might be used for disease control. By mulching the soil with transparent polyethylene sheets in the hot season prior to planting, a team of Israeli workers developed a solar heating approach for soil disinfestation (40). The solar heating of soil is a soil disinfestation method for disease control. As such, it aims to eradicate or reduce, prior to planting, using drastic means, the inoculum existing in the soil. The final goal is to achieve an economic reduction in disease incidence for at least one season. Many studies using this approach to disease and weed control have been carried out in Israel (15, 18, 26, 27, 32-34, 39-42, 48-50, 69, 70, 81) and