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bioRxiv · 10.1101/2021.07.23.453522

Nano-Insecticides Against the Black Cutworm Agrotis ipsilon (Lepidoptera: Noctuidae): Toxicity, Development, Enzyme activity, and DNA Mutagenicity

Abstract

High-frequency doses of chemical pesticides cause environmental pollution with high pesticide residues. In addition, increasing insecticide resistance in many insect pests requires novel pest control methods. Nanotechnology could be a promising field of modern agriculture, and is receiving considerable attention in the development of novel nano-agrochemicals, such as nanoinsectticides and nanofertilizers. This study assessed the effects of the lethal and sublethal concentrations of chlorantraniliprole, thiocyclam, and their nano-forms on the development, reproductive activity, oxidative stress enzyme activity, and DNA changes at the molecular level of the polyphagous species of black cutworm Agrotis ipsilon. The results revealed that A. ipsilon larvae were more susceptible to the nano-formsthan the regular forms of both nano chlorine and sulfur within the chlorantraniliprole and thiocyclam insecticides, respectively, with higher toxicities than the regular forms (ca. 3.86, and ca.2.06-fold, respectively). Significant differences in biological parameters, including developmental time and reproductive activity (fecundity and hatchability percent) were also observed. Correspondingly, increases in oxidative stress enzyme activities were observed, as were mutagenic effects on the genomic DNA of A. ipsilon after application of the LC50 of the nano-forms of both insecticides compared to the control. The positive results obtained here have led us to apply these nano-forms indifferent insect models in additional studies.

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Awad, M. A. M., Ibrahim, E.-D. S., Osman, E. I., Elmenofy, W. H., Mahmoud, A. W. M., Atia, M. A. M., Moustafa, M. A. M.. 2021-07-23. Nano-Insecticides Against the Black Cutworm Agrotis ipsilon (Lepidoptera: Noctuidae): Toxicity, Development, Enzyme activity, and DNA Mutagenicity. https://doi.org/10.1101/2021.07.23.453522

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