38th Annual Meeting of the Society for Invertebrate Pathology

The East African highland banana is the principal staple crop of the Great Lakes region of eastern Africa. The banana weevil, Cosmopolites sordidus, is the most important insect pest of highland banana. The larvae bore in the corm, reducing nutrient uptake and weakening the stability of the plant. Beauveria bassiana is especially important for controlling cryptic pests such as banana weevils. Various B. bassiana strains were isolated from banana weevil cadavers or soils in banana fields and have been tested in the laboratory. The most promising strains resulted in >90% larval mortality in 3 weeks. However, field efficacy of these promising strains against banana weevils is a key for development of a microbial control program. Various formulation methods (such as maize bran or millet waste) and their field delivery systems (using banana suckers, pseudostem traps or soil around the banana stems) have been tested. Results were variable and demonstrated that formulation methods and field delivery systems need to be integrated with prevailing agroecological conditions, such as soil types and management practices. Currently, pheromone- and kairomone-based traps are being investigated, alongside the use of B. bassiana as an artificial endophyte in banana tissue culture plants.