insecticide

Crop dusting: spraying crops with insecticide and pesticide from an aeroplane. Spraying the crops in this way allows a large area to be sprayed quickly and also avoids having to drive vehicles through fields, thus potentially damaging the crops.

Any chemical pesticide used to kill insects. Among the most effective insecticides are synthetic organic chemicals such as DDT and dieldrin, which are chlorinated hydrocarbons. These chemicals, however, have proved persistent in the environment and are also poisonous to all animal life, including humans, and are consequently banned in many countries. Other synthetic insecticides include organic phosphorus compounds such as malathion. Insecticides prepared from plants, such as derris and pyrethrum, are safer to use but need to be applied frequently and carefully.