Efficacy of the Entomopathogenic Fungus, Metarhizium anisopliae for Control of Maize Weevil Sitophilus zeamais Mots (Coleoptera-Curcuiionidae)
EKESI, S., ONU, I., AKPA, A.D., DIKE, M.C. and MANIANIA, N.K.
ABSTRACT: The virulence of eight isolates of entomopathogenic fungus, Metarhizium anisopliae, to
the maize weevil, Sitophilus zeamais, was bioassayed in the laboratory. All the isolates tested were pathogenic to the weevil but to varying degrees. Isolates ICIPE 45 and 47 were superior to all other isolates in terms of mortality on adult weevils, protection of grains from damage and reduction in progeny production by the weevil. There were no significant differences between Pirimiphos-methyl-treated maize and maize treated with dry conidia of isolates ICIPE 45 and 47 in relation to adult weevil mortality, damage to maize grain and progeny emergence on maize at seven days post treatment. Both isolates persisted for more than six months on maize grain achieving up to 60 to 100% mortality at 7 days post treatment.