Toxicity Effects of Biosynthesized Silver Nanoparticles Mediated Petiveria alliacea Extracts on Mos-quito (Aedes aegypti L.)

Abstract

Background: Mosquitoes transmit diseases like malaria and dengue, causing significant health risks. Synthetic insecticides are commonly used for control, they have harmful effects on humans, animals, and the environment. This research evaluates the insecticidal efficacy of Silver nanoparticles synthesized from Petiveria alliacea root (PaR-AgNPs) and Petiveria alliacea leaf (PaL-AgNPs) against larvae and adults Ae. Aegypti. Methodology: The nano-insecticides were applied at four different concentrations (25, 50, 75, and 100%) v/v with four repli-cates arranged in a completely randomized design. Synthetic insecticides (Deltamethrin) and control were included in the treatments which were carried out at the Nigeria Institute of Medical Research (NIMR), Lagos, Nigeria. Silver nitrate was used in the biosynthesis of AgNPs by P. alliacea leaf (PaL-AgNPs) and root (PaR-AgNPs) with maxima absorbance ranging from 5.95-76.91 nm in size. Results: The results showed that the biosynthesized AgNPs exhibited both larvicidal and adulticidal effects on the targeted mosquito. Also, the efficacy of the tested nano-insecticides is influenced by concentration and hours of exposure. The tested nano-insecticides achieved 100 % larval mortality at 100% v/v after 48 hours of exposure. PaR-AgNPs and PaL-AgNPs demonstrated similar effectiveness in controlling Ae. aegypti larvae. However, PaR-AgNPs showed a significantly higher mortality (100%) compared to PaL-AgNPs, which caused 97.5% and 95.0% mortality in adult mosquitoes through contact and fumigant bioassays respectively, at 100% v/v after 48 hours of exposure. However, the tested nano-insecticides had a delayed effect compared to Deltamethrin. Conclusion: This study showed how plant-based AgNPs can serve as efficient larvicides and adulticides in the control of disease vectors