Augmentative releases of entomophagous species in annual cropping systems

Augmentative releases, because of their repetitive nature, are often more expensive and time consuming than importation methods of biological control, and thus have been considered a less desirable approach to biological control. From the view of semipermanent ecosystems, e.g., orchards, this perspective may be appropriate; however, for annually disturbed habitats, periodic releases may be the biological control method of choice. Matching the characteristics of annual cropping systems to appropriate natural enemies would expand the basis for using entomophagous species in augmentative releases. When this approach is used, selection of natural enemies for augmentative releases would move beyond the ability to mass rear entomophagous species. A focus on quality control, enhanced effectiveness of released individuals, and ecological and economic assessment of releases is required to increase the use of augmentative biological control in annual cropping systems. Increased knowledge of the biosystematics and basic biology of entomophagous species is necessary to use these species effectively in augmentation programs.