pesticide – n. a chemical that is used to kill animals or insects that damage plants or crops
habitat – n. the place or type of place where a plant or animal naturally or normally lives or grows
fungus – n. any one of a group of related plants (such as molds, mushrooms, or yeasts) that have no flowers and that live on dead or decaying things (singular of fungi)
parasite – n. an animal or plant that lives in or on another animal or plant and gets food or protection from it
insecticide – n. a chemical substance that is used to kill insects
larva – n. a very young form of an insect that looks like a worm
strain – n. a kind or sort of something (usually + of)
toxic – adj. containing poisonous substances