Host Specificity Assessment of European Peristenus Parasitoids for Classical Biological Control of Native Lygus species in North America: Use of Field Host Surveys to Predict Natural Enemy Habitat and Host Ranges

The Lygus bug complex (Het., Miridae) at many sites in North America causes economic damage to a wide variety of agricultural crops and is the focus of numerous research projects. Lygus can be best suppressed using parasitoids in unsprayed non-cropping situations as well as in crops where pollination is important for maximizing yields. The European parasitoid Peristenus digoneutis Loan (Hym., Braconidae), which attacks several species in the genera Lygus and Adelphocoris in Europe, has been established in the eastern USA to control the native pest Lygus lineolatus (Palisot de Beauvois) in alfalfa. The success of this project has stimulated interest into the potential for the establishment of additional European species for biological control of pest Lygus bugs in several regions of North America. The research of this ongoing case study concentrates on assessing strategies and methods for host specificity testing of these parasitoids in relation to Europe and North America. Predicting the impact of European parasitoids by using existing and new knowledge of the host range and habitats in the area of origin will aid in choosing Peristenus species for further release in other regions and will have important implications for the practice of classical biological control.