A biopesticide is a biological substance or organism that damages, kills, or repels organisms seen as pests. Biological pest management intervention involves predatory, parasitic, or chemical relationships.
They are obtained from organisms including plants, bacteria and other microbes, fungi, nematodes, etc. They are components of integrated pest management (IPM) programmes, and have received much practical attention as substitutes to synthetic chemical plant protection products (PPPs).
The U.S. Environmental Protection Agency states that biopesticides "are certain types of pesticides derived from such natural materials as animals, plants, bacteria, and certain minerals, and currently, there are 299 registered biopesticide active ingredients and 1401 active biopesticide product registrations." The EPA also states that biopesticides "include naturally occurring substances that control pests (biochemical pesticides), microorganisms that control pests (microbial pesticides), and pesticidal substances produced by plants containing added genetic material (plant-incorporated protectants) or PIPs".
The European Environmental Agency defines a biopesticide as “a pesticide made from biological sources, that is from toxins which occur naturally. - naturally occurring biological agents used to kill pests by causing specific biological effects rather than by inducing chemical poisoning.” Furthermore, the EEA defines a biopesticide as a pesticide in which “the active ingredient is a virus, fungus, or bacteria, or a natural product derived from a plant source. A biopesticide's mechanism of action is based on specific biological effects and not on chemical poisons.”
Biopesticides usually have no known function in photosynthesis, growth or other basic aspects of plant physiology. Many chemical compounds produced by plants protect them from pests; they are called antifeedants. These materials are biodegradable and renewable, which can be economical for practical use. Organic farming systems embraces this approach to pest control.