Potential of Adult Carabids (Coleoptera: Carabidae) as Predators of Fifth-Instar Codling Moth (Lepidoptera: Tortricidae) in Apple Orchards in California

Abstract

This investigation compared the potential of adult carabids (ground beetles) as predators of fifth-instar codling moth, Cydia pomonella (L.). The three objectives of the research were the following: (1) to determine which species could kill C. pomonella , (2) to compare the degree of carnivory and consumption pattern of selected species of carabids, and (3) to estimate carabid predation of C. pomonella in the field. The results indicated that 75% or more of Pterostichus lustrans LeConte, Pterostichus cursitor LeConte, Pterostichus (Hypherpes) spp., Harpalus pensylvanicus DeGeer, or Anisodactylus californicus Dejean individuals were capable of killing C. pomonella in the laboratory. The most effective predators were species of Pterostichus , even when an alternative plant food (rolled oats) was provided. An average of 60% of tethered C. pomonella were consumed each night by carabids in early June, but predation intensity declined June–July. The carabid species seen attacking tethered prey included Agonum punctiforme Say, Calathus ruficollis Dejean, H. pensylvanicus , and P. (Hypherpes) spp. Adults of Pterostichus species appear to be important early-season predators of C. pomonella in orchards.