Mechanical Release of Predators to Control Colorado Potato Beetle, Leptinotarsa decemlineata (Say)

Abstract

In agriculture, chemical insecticides are widely used to protect crops from insect pests. Over a period of years, some insects such as Colorado potato beetle, Leptinotarsa decemlineata (Say), succeed in developing resistance to most of the registered chemical insecticides. In the case of this particular pest, heavy applications of chemical insecticides to control it become ineffective on a long-term basis and can lead to serious health and environmental problems. The use of natural enemies to control Colorado potato beetle is an interesting alternative to chemical means. However, hand release of predators is not feasible on a large scale in the field because it is time-consuming and not even conceivable. The main objective of this research study was to investigate the technical feasibility of mechanically releasing predators in potato fields to control Colorado potato beetle. Trials using a test bench specifically designed and built for this purpose showed that a carrier material was required because most of the predators clung firmly to the walls of the release system and hence remained inside. When mixed with a carrier material, all the predators were successfully released. The success of this mass predator release system will be highly valuable for the biological control of insect pests in many crops, including potato, strawberry, and lettuce.