Nanotechnology will make agriculture eco-friendly and profitable by reducing the concentration of insecticides used, which is appreciable from the environmental safety perspective. Toxicity of spirotetramat alone and its mixtures with nanosilica against nymphs of Aphis gossypii (Hemiptera: Aphididae) and adults of Bemisia tabaci (Hemiptera: Aleyrodidae) was evaluated through laboratory and field experiments during two years (2020 and 2021). The possible impact of treatments on Eisenia fetida (Oligochaeta: Lumbricidae) was also assessed. The enzymatic activity of carboxylesterase (CarE) and glutathione S-transferase (GST) in tested insects and earthworm was estimated. Toxicity of spirotetramat was increased when mixed with nanosilica at 250, 500, 1000 mg L -1 , ratios were 1.13, 1.91 & 2.59 -fold on A. gossypii, 1.12, 1.41 & 2.26 -fold on B. tabaci and 1.05, 1.17 & 1.46 -fold on E. fetida, respectively. Spirotetramat and nanosilica at 1000 mg L -1 mixture gave the highest significantly increased in CarE activity of A. gossypii and B. tabaci (11.42 and 9.33 μmol min -1 mg protein -1 ), and decreased the GST activity (1.54 and 1.69 μmol min -1 mg protein -1 ), respectively, relative to the control. While, the same previous mixture on E. fetida increased the enzyme activity of CarE and GST (13.37 and 3.36 μmol min -1 mg protein -1 ), respectively, compared to the control. Additionally, the mixture of spirotetramat and nanosilica at 1000 mg L -1 recorded the highest population reduction percentages in A. gossypii (92.5 and 95.5 %) and B. tabaci (79.9 and 84.4 %) compared with spirotetramat alone (88.6 and 90.7%) for A. gossypii, (73.6 and 78.9%) for B. tabaci during 2020 and 2021 cotton seasons, respectively.

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