Adulticidal activity against houseflies (Musca domestica L.; Muscidae: Diptera) of combinations of Cymbopogoncitratus and Eucalyptus globulus essential oils and their major constituents

Abstract

The efficacies of Cymbopogon citratus, Eucalyptus globulus, eucalyptol, geranial, and their combined formulations against houseflies (Musca domestica) were evaluated and compared to cypermethrin, a common synthetic insecticide. Using a standard susceptibility assay that the World Health Organization (WHO) advises, the knockdown and mortality rates were calculated. The tested concentration range of these essential oils and their constituents was between 1% to 5%. The highest efficacy (100% knockdown rate and mortality rate) were provided by a combined formulation of 2% E. globulus EO + 1% geranial. This formulation had a KT50 of 4.27 min. The two next best formulations were 2% C. citratus EO + 1% eucalyptol that provided a KT50 of 5.85 min and an individual 5% C. citratus EO that provided a KT50 of 6.69 min. Most importantly, several tested formulations provided a higher knockdown rate than 1% cypermethrin. Therefore, these formulations have a full potential as an alternative natural insecticide to replace cypermethrin.