The Alleviating Effect of Straw-Derived Nitrogen-Doped SiO ₂ Nanozymes for Wheat Growth under Drought Stress

Nanozymes have shown the potential to alleviate drought stress, but the exact regulatory mechanism of the nanostructure in wheat remains unclear. Herein, wheat straw-derived nitrogen-doped silica nanoparticles (N-SiO 2 NPs) were successfully synthesized via the calcination method, which exhibits peroxidase (POD) like activity and excellent hydrophilicity. Under the 5% polyethylene glycol (PEG) drought stress condition, treatment with 5.0 mg/L N-SiO 2 NPs can significantly alleviate growth inhibition in wheat, increasing root length, shoot fresh weight, and dry weight by 19.43%, 76.41%, and 48.42%, respectively. Additionally, Chlorophyll a and b increased by 35.41% and 135.92%, respectively, while the levels of malondialdehyde (MDA) and hydrogen peroxide oxidation indicators decreased by 35.41% and 22.12%, respectively. Furthermore, N-SiO 2 NPs significantly enhanced the wheat antioxidant enzyme system based on the activities of catalase (CAT) and POD, thereby mitigating the oxidative stress experienced by the plants. Our finding reveals the potential application of nanozymes in sustainable agriculture.