Representative Examples of Insect Pests
and their Biocontrol Agents
Cottony cushion scale (Icerya purchasi). This pest of citrus is kept in check by Rodolia cardinalis, a ladybeetle introduced from Australia.
Woolly apple aphids (Eriosoma lanigerum). In apple orchards of the northeastern and northwestern U. S., these aphids are controlled by Aphelinus mali, a chalcid parasite native to Europe.
Alfalfa weevils (Hypera postica). An ichneumonid wasp (Bathyplectes curculionis) parasitizes this beetle’s larvae and a braconid wasp (Microtonus aethiopoides) parasitizes the adults.
Cassava mealybugs (Phenacoccus manihoti). This pest spread throughout much of tropical Africa in the 1980’s, but it has been largely brought under control by an encyrtid wasp (Apoanagyrus lopezi) discovered in South America.
Oriental fruit flies (Dacus dorsalis). In Hawaii, these pests of mangoes and other fruits are commonly held in check by Opius oophilus, a braconid wasp from the Philippine Islands.
Purple scale (Lepidosaphes beckii). In California citrus groves, this pest is successfully controlled by ladybeetles (Chilocorus spp.) and parasitic wasps (e.g. Aphytis lepidosaphes).
Winter moths (Operophtera brumata). In Canada, these insects are pests of forest and shade trees. They have been successfully controlled by Cyzenis albicans (a tachinid fly) and Agrypon flaveolatum (an ichneumonid wasp).
Cereal leaf beetles (Oulema melanopus). This species is a pest of small grains in the midwestern U. S. Its eggs are attacked by a mymarid wasp (Anaphes flavipes), its larvae are parasitized by a eulophid wasp (Testrastichus julus), and adults are susceptible to a fungal pathogen (Beauveria bassiana).
Blotch leafminers (Agromyza frontella). In the eastern U. S., this pest of alfalfa is parasitized by a braconid wasp (Dacnusa dryas) and a eulophid wasp (Aphytis yanonensis) introduced from China.
Coconut moths (Levuana iridescens). In Fiji, these pests were brought under control by introducing Ptychomyia remota, a tachinid fly from Malaysia.
Green stink bugs (Nezara viridula). Tachinid flies (Trichopoda spp.) from Antigua and Monserrat were released in Hawaii to control this pest of vegetable crops.
Palm scale (Chrysomphalus dictyospermi). This insect pest attacks ornamentals and greenhouse plants. In Greece, it is largely controlled by Aphytis melinus, a eulophid wasp introduced from California.