Beneficial insects and mites, also known as natural enemies, reduce pest populations in orchard ecosystems via parasitism or predation, termed biological control. Parasitoids are smaller than prey and slowly kill them by developing as external or internal parasitic larvae. Predators are free-living beneficials that are as large or larger than their prey and kill and consume more than one prey item in their lifetimes. Use of beneficials can be classified into one of the following categories: conservation, augmentation, inundation, or introduction. Conservation involves creating favorable habitat for beneficials by reducing pesticide applications that harm beneficials and adding alternate food sources. Augmentation involves releases of mass-reared beneficials to bolster existing populations. Inundation also utilizes releases of mass-reared beneficials but with the goal to saturate the system and control pest populations within one generation. Introduction, or classical biological control, involves the release of an exotic beneficial to control a pest; this method is generally most effective when the pest is also an exotic member of an ecosystem and therefore has no effective natural enemy present. The most common approaches used in orchard ecosystems are conservation and augmentation.
Was this article helpful?