Trichogramma wasps
Introduction
Identification
Biology
As a biological control
Several species of Trichogramma wasps exist, all of which attack and kill various kinds of insect eggs. Insect larvae already hatched are not susceptible to Trichogramma attack. Eggs that Trichogramma will parasitized are from insects in the order Lepidoptera (moths and butterflies), which includes cutworms, codling moth, cabbageworms and armyworms. Commercially available Trichogramma wasps are often used as a form of a biological insecticide where they are expected to eliminate most of the developing eggs of pests shortly after release. High levels of control are not often achieved in practice, but the wasps may effectively supplement existing controls. Multiple releases of Trichogramma wasps are recommended, since persistence of the parasites may be short-term. Several different species of Trichogramma wasps are produced (e.g., T. minutum, T. platneri, T. pretiosum) and they have different habits. The more sophisticated suppliers will provide advice on which species is most appropriate for the intended crop and pest.
