Enhancing deltamethrin phytoremediation and its metabolism in polluted soil through the interaction of <i>Plantago major</i> and different agents: toxicokinetic study, biochemical analysis, gene expression, and metabolic pathways

Deltamethrin (DMT), a toxic pyrethroid insecticide, contaminates soil and water, posing risks to humans and organisms. Phytoremediation using <i>Plantago major</i> was studied to remove DMT and its metabolites from polluted soil, enhanced by liquid silicon dioxide (SiO₂, 750 mg L^-1) and <i>Bacillus subtilis</i> AZFS3 (<i>B. subtilis</i>),10⁷ CFU/mL) under greenhouse conditions. Our study assessed biochemical responses, including superoxide dismutase (SOD), catalase (CAT), hydrogen peroxide (H₂O₂), malondialdehyde (MDA), and detoxification gene expression in <i>P. major</i> roots and leaves subjected to DMT stress. SiO₂ and <i>B. subtilis</i> desorbed DMT by 46.08 and 18.75 µg g^-1, respectively. The longest half-life (t₁/₂) of DMT was 23.22 days in polluted soil alone, while the shortest (5.81 days) was observed in soil with <i>P. major</i> and <i>B. subtilis</i>. Soil with <i>P. major</i> plus SiO₂ reduced DMT residues more effectively than <i>B. subtilis</i> and increased DMT accumulation in plant tissues. SOD and CAT activity peaked in roots and leaves treated with SiO₂ and B. SUBTILIS, with lower H₂O₂ and MDA contents observed in SiO₂ treatments. Additionally, DMT stress induced significant upregulation of cytochrome P450, glutathione S-transferases (GST), glycosyltransferases (GTs), and ABC transporter genes in <i>P. major</i>. SiO₂ was more effective than <i>B. subtilis</i> in enhancing phytoremediation by promoting DMT degradation and metabolic detoxification pathways. This study highlights the potential of combining SiO₂ and <i>B. subtilis</i> with phytoremediation to accelerate DMT removal and mitigate harmful pesticide residues in polluted soils and plants.