Characterization and Insecticidal Efficacy of Green-Synthesized Silver Nanoparticles Against Four Stored Product Insect Species

TL;DR

This study shows that silver nanoparticles made from Galega officinalis leaves can effectively kill four common stored-product insect pests in a dose-dependent manner.

Contribution

The novelty lies in the green synthesis of AgNPs using Galega officinalis and their evaluation against multiple stored-product insect species.

Findings

AgNPs synthesized using Galega officinalis showed high insecticidal activity, with 100% mortality in Tribolium confusum at 1000 ppm.

The nanoparticles were characterized as spherical with an average size of 25.07 nm and demonstrated stability with a zeta potential of −22 mV.

Tribolium confusum and Ephestia kuehniella were the most susceptible to the AgNPs, suggesting their potential for eco-friendly pest control.

Abstract

This study describes the green synthesis of silver nanoparticles (AgNPs) using Galega officinalis leaf extract and their insecticidal effects against four stored-product pests: Sitophilus granarius, Tribolium confusum (adults), Plodia interpunctella, and Ephestia kuehniella (larvae). AgNPs were characterized by UV–Vis, FTIR, DLS, and TEM. Bioassays using AgNPs (10–1000 ppm) mixed in flour and diet showed dose-dependent mortality after 7 and 31 days, respectively. The highest susceptibility was observed in T. confusum and E. kuehniella. These results suggest the potential of G. officinalis-based AgNPs as eco-friendly candidates for stored pest control.

This study aimed to biosynthesize silver nanoparticles (AgNPs) using aqueous leaf extract of Galega officinalis and to evaluate their insecticidal activity against key stored-product pests. AgNP formation was confirmed through UV–vis spectroscopy, which showed a surface plasmon resonance peak at 380 nm. FTIR analysis indicated the presence of plant-derived functional groups likely involved in the reduction and stabilization of Ag+ ions. Dynamic light scattering revealed an average hydrodynamic diameter of 25.07 nm, a PDI of 0.39, and a zeta potential of −22 mV, while TEM images showed predominantly spherical and polydisperse particles ranging from 4.3 to 42.4 nm. Insecticidal bioassays performed on Sitophilus granarius, Tribolium confusum, Plodia interpunctella, and Ephestia kuehniella revealed concentration-dependent mortality. The highest mortality rates were recorded at 1000 ppm, reaching 100% in T. confusum, 83.33% in P. interpunctella, and 76.67% in both S. granarius and E. kuehniella. These findings demonstrate the potent insecticidal activity of G. officinalis-mediated AgNPs and support their potential as environmentally friendly alternatives for stored-product pest management, warranting further studies on safety, large-scale synthesis, and integration into pest-control programs.

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