This Encyclopedia provides coverage of a wide range of topics contributed by experts world wide. The work emphasizes the chemicals used in agriculture for management of pests, their development, use, metabolism, toxicology and mode of action. These chemicals include pesticides, such as the herbicides (weed killers), insecticides and fungicides. Applications of biotechnology are included as are discussions of natural products and growth regulators. Fertilizers and soil fertility are covered at length as well as the persistence of pesticide residues, their degradation, environmental transport and implications of their residues in the environmental. Toxicological and regulatory implications are included throughout.