Production and use of bacterial insecticides

Abstract

Among the biocontrol agents used in the world, the entomopathogenic bacilli are of special importance, Bacillus thuringiensis (Bt) products have been commercialized for more than 50 years, with an annual market of 60 to 80 million dollars. It is expected that the use of Bt will implement, as stricted environmental protection regulations are adopted, and more efficient and less expensive products become available. The bioinsecticide market for vectors control might also significantly improve. Today, a product based on B. thuringiensis israelensis is being used to control simulids and mosquitoes of the gennus Aedes. , B. sphaericus products, effective against Culex, are in the final stage of development. A field work is being conducted in Brasília, where chemical larvicides were substituted by B. sphaericus, keeping the same control level. Much progress is being made with bacterial bioinsecticides, mainly in the isolation of more efficient strains for different insect pests, in the development of fermentation (culture media, process condition and operation) and more stable and persistent formulations. Through molecular biology, new concepts are being formulated for plant protection against insect attack, such as transgenic plants and packed toxins. This allows to predict that the entomopathogenic bacilli will continue to be used for many years, either directly or as source of genetic material.