Factors in the Success and Failure of Microbial Insecticides in Forestry

The minor position of microbial insecticides within the global pesticide market can be attributed to a number of causes, including high cost of production, high specificity, poor application technology, poor persistence and slow speed of kill. These aspects are discussed in relation to the potential for use of microbial insecticides against forest pests. Many of the constraints are not limiting in forestry and some of the ways in which they can be overcome are discussed, including the concept of a better appreciation of the ecological context. This approach encompasses knowledge of the behaviour of the target host species, both for improved targeting and for maximum exploitation of secondary inoculum. These, and other aspects are brought together in discussing the future for microbial insecticides in forest pest management.