Authors: O.E. Fgade, S.A. Balogun, C.J. Lomer
International lnstitute for Tropical Agriculture, Biological Control and Functional Biodiversity Centre, BP 08-0932 Cotonou, Benin Republic.
Abstract
Microbial control of caged populations of Zonocerus variegatus was carried out using indigenous
fungal entomopathogens isolated from the grasshopper’s cadaver. Bioassay response indicated a
dose-dependent mortality coupled with drastic reduction in food consumption among spores infected
grasshoppers. Lethal time (LT/sq) of 4.6 days for 103 spores/ml and 3.8 days for 10 spores/ml of oil
formulation of Beauveria bassiana were observed. While Metarhizium sp recorded LT50 of 9.0 days and 2.8 days for 103 and 107 spores/ml, respectively. The-results obtained were discussed in relation to use of the isolates in the control Z. variegatus infestation in forest agro-ecosystem of south west, Nigeria.