A mass-rearing method for the assassin bug Pristhesancus plagipennis (Hemiptera : Reduviidae)

Pristhesancus plagipennis (Walker) is a predator of larvae and nymphs of ma ny pestiferous insects for which natural enemies are not commercially avail able. This paper describes a containerized mass-rearing method for P. plagi pennis using hot water-killed larvae of Tenebrio molitor (L,) and Helicover pa armigera (Hubner). In addition, the effect of P. plagipennis density dur ing nymphal rearing and adult oviposition was investigated. The rearing met hod minimizes P. plagipennis cannibalism, avoids the need for live insect p rey, and is space and labor efficient. Larvae of the yellow mealworm, T. mo litor, were the most suitable prey for minimizing nymphal development time and mortality while producing insects with the highest body weight. When re ared on a diet of T. molitor, the optimum rearing density was 20-27 nymphs per B-liter container. This rearing density minimized nymphal mortality to 16-22%. The optimum density for oviposition was 16 adults per B-liter conta iner, which provided the best compromise between egg production and space u tilization. (C) 2000 Academic Press.