Abstract:

For effective use of the entomopathogen Beauveria bassiana in the management of the banana weevil, high inoculum levels and appropriate formulations are mandatory. Equally important is the development of a suitable formulation that is persistent within the target environment, in this case the field soil ecosystem. Evaluations of Beauveria bassiana were carried out from Kawanda, Uganda on conidial yield from selected substrates, efficacy of different formulations against the banana weevil, and, efficacy and persistence of the fungus under organic and inorganic soil amendments. The substrates evaluated were cracked maize, maize bran, “machicha”, bagasse, cotton husks, maize bran + bagasse, maize bran + cotton husks, and bagasse + spent yeast and they were formulated with clay or loam soils. The soil amendments evaluated were un-amended soils, coffee husks, decomposed cowdung manure and inorganic fertilizers. The results indicated that cracked maize grains were the most ideal for B. bassiana conidia production while the dried formulation of the same media was also the most effective against the banana weevil under laboratory conditions. The formulation gradually lost its efficacy as storage period increased. Overall, the soil amendments significantly reduced the efficacy entomopathogenic fungus over time.