Environmental Impacts of Microbial Control Agents Used for Control of Invasive Pests

Abstract

A range of bacteria, viruses, fungi, protists and nematodes has been used for control and eradication of invasive pests. Insect pathogens vary in key charac- teristics such as specificity, mode of action and persistence, all of which determine their safety profile with respect to impacts on non-target species. Laboratory testing against beneficial species and post-application monitoring of impacts support the view that, while they are not entirely free of hazards to non-target organisms, in comparison with other control methods these microbial control agents are environ- mentally benign. When considering actions against new pest incursions, where the potential for damage to crops and/or impacts on indigenous ecosystems is enor- mous, rapid steps must be taken to mitigate or eradicate these pests. In such situa- tions, biopesticides can be attractive control options, and their use is likely to have minimal impact on beneficial and other non-target species. Such advantages have been clearly demonstrated with Bacillus thuringiensis, which has not precipitated any major ecological disturbances, even when used in very intensive and prolonged eradication programmes