ABSTRACT
The science of biological control is only a century old and has primarily concentrated on insects until recently. Traditional farmers have used biological control through their development of suppressive soils and the use of antagonistic plants. A number of plants contain chemical compounds that are antagonistic to various plant pathogens. Cook and Baker cite Chinese agriculture as an example of "the extensive adoption of biological control measures." The relationship between cultural control and biological control should always be kept in mind when planning or analyzing plant disease management strategies. Cook and Baker define suppressive soils as soils in which disease development is suppressed, although pathogens are introduced in the presence of a susceptible host. Pathogens are often killed by heat generated during the composting process, and many diseases are suppressed by the use of composts.
