Encarsiaformosa

Encarsia formosa is a tiny parasitoid wasp in the family Aphelinidae that is widely used as a biological control agent against the greenhouse whitefly, Trialeurodes vaporariorum, in protected cropping systems such as greenhouses and tunnel houses. It is distributed worldwide and produced commercially for augmentation programs.

The female Encarsia formosa lays eggs inside the immature stages of whiteflies on the undersides of leaves. The developing larva feeds within the host, eventually killing it, and the adult wasp emerges from the host through a circular exit hole. The life cycle from egg to adult is temperature dependent, typically taking about two to three weeks under moderate warm conditions, with females capable of producing multiple offspring during their lifespan.

The primary target of E. formosa is the greenhouse whitefly. It may occasionally parasitize other whitefly species sharing the same habitat, but its effectiveness on non-target hosts is generally lower. It is regarded as a specialist parasitoid of whiteflies, contributing to the suppression of whitefly populations in appropriate environments.

In pest management, Encarsia formosa is released as part of augmentative biological control programs in greenhouses. Releases are coordinated with population monitoring and are often used in combination with other integrated pest management practices. The parasitoid performs best in warm, humid conditions and can be affected by residual insecticides or extreme temperatures, which can reduce its efficacy.

Historically, E. formosa was among the first biological control agents employed against greenhouse whiteflies and remains a staple in modern IPM programs for protected crops.