Microbial control of caged population of Zonocerus variegatus using Beauveria bassiana and Metarhizium sp.

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 (LT₅₀) of 4.6 days for 10³ spores/ml and 3.8 days for 10⁷ 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. variegates infestation in forest agro-ecosystem of south west, Nigeria.

Key Words: Microbial control, entomopathogenic fungi, Beauveria bassiana, Zonoccrus variegatus, Metarhizium sp.

African Journal of Biotechnology Vol.4(1) 2005:113-116