Impact of biopesticides on resistant Aedes aegypti (L.) and Aedes albopictus (Skuse) populations from Penang Island based on metabolic enzymes analysis

Abstract

The development of resistance towards pyrethroid insecticide in Malaysia has been notably observed. This study aimed to evaluate the impact on enzymatic activities of mixed function oxidase and esterases using biochemical assays in insecticide-resistant Ae. aegypti and Ae. albopictus from urban and suburban areas in Penang Island after exposure to biopesticides. Prior to biopesticide treatment, the susceptibility status was confirmed that both Aedes species field strains were resistant to 0.75% permethrin and 5% malathion. In this study, Ae. Albopictus urban treated with I. cairica leaf extracts and Meta-G4 demonstrated the highest upregulated enzyme activities. However, Ae. aegypti suburban and urban strains treated with I. cairica leaf extracts demonstrated the lowest downregulated enzyme activities. It can be concluded that, Ae. albopictus that were resistant to insecticides showed reduced tolerance to I. cairica leaf extracts and Meta-G4, but this effect was less pronounced in Ae. aegypti.