The study examined the effect of nano-silica extracted from two different plant sources on the survival and development of the potato tuber moth, Phthorimaea opercullela. The silica powder was derived from two different agricultural byproducts, olive stones and corncobs. Characterization by X-ray diffraction revealed that the extracted powder has an amorphous silica phase. The nitrogen adsorption-desorption measurements revealed that both extracted and treated silica have mesoporous structure, with a specific surface area of around 300 m2/g and 270 m2/g for the silica derived from olive stones and corncobs, respectively. The silica nanoparticles (SiO2 NPs) prepared from the silica derived from olive stοnes showed higher larvae mortality, pupae weight, and larval and pupal developmental time, compared to the silica derived from corncombs. The results show that the nano-silica derived from agriculture byproducts can be as effective as the synthetic insecticide (deltamethrin) utilized in control of the potato tuber moth, with lower environmental impact in terms of preventing pesticide residue accumulation. In addition, the efficiency of SiO2 NPs applications depends on the source of the silica nanoparticles and the applied concentration to achieve the optimum results for the pest control.
