ABSTRACT
Physical methods of disease prevention and control are based on the physiological tolerance of disease agents to adverse conditions such as increased or low temperature, absence of moisture, presence of deleterious irradiation; and the removal of pathogen sources or presence of physical barriers to prevent contact between the disease agent and the host. Application of physical techniques involving the use of heat, solar energy and irradiation may reduce the pathogen population or weaken their pathogenic potential. Heat treatments are applied as hot air, hot water, aerated steam and solarization. Soil solarization can be used to control nematodes, however, results may be variable because nematodes are mobile and can move to greater depths to escape lethal temperatures. In order to eliminate the extra heat brought in from the field and avoid the development of new or latent infections, regular refrigeration is occasionally followed by a fast hydro cooling or air cooling.
