‘Pesticide’ is an umbrella term for any substance which is designed to control a pest or disease. Types of pesticides include herbicides (designed to kill plants), insecticides (insects), fungicides (fungi), rodenticides (rodents) and molluscicides (molluscs). The term also includes synthetic plant growth regulators (which modify plant development so they can grow out of season), defoliants (that accelerate leaf fall) and desiccants (which dry leaves out so they can be harvested).
