Mitigation impact of SiO₂ nanoparticles and mycorrhiza on wheat growth and yield under late-season drought stress

Wheat grain yields are reduced due to late-season drought, posing a challenge for cultivated areas that experiencing water scarcity. This research explores the impact of Nano-SiO₂ and mycorrhiza on wheat, aiming to mitigate drought effects. A two-year experiment was carried out with three factors and three replications. The factors were the interruption of irrigation (control, stopping irrigation at the end of the booting stage and stopping irrigation at the end of the flowering stage), foliar application of Nano-SiO₂ (0, 40 and 80 mg L⁻¹) and mycorrhiza application (0 and 200 kg ha⁻¹). The results indicated that drought stress decreased leaf area index, variable fluorescence (Fv), Fv/maximum fluorescence (Fm), stomatal conductance, net photosynthesis, sub stomatal CO₂ concentration and grain yield. Drought stress increased the grain protein percentage, and stomatal density. Application of Nano-SiO₂ and mycorrhiza increased grain yield. Nano-SiO₂ balances stomatal conductance and makes plants more drought-resistant by increasing the amount of silicon in leaves, leading to improved yield. Conversely, mycorrhiza may have played an important role in absorbing phosphorus and other elements from the soil in addition to absorbing moisture, which ultimately resulted in a drought-resistant plant. The combined treatment of mychorriza + foliar application of Nano-SiO₂ (80 mg L⁻¹) increased grain yield by 39.43% under severe drought conditions (stopping irrigation at the end of the booting stage). In summary, the soil application of mycorrhiza and foliar Nano-SiO₂ is recommended for wheat production in regions where water deficit is a common issue during late-season wheat growth stages. Exploring the utilization of Nano-SiO₂ over an extended period throughout the wheat growth, alongside mycorrhiza application, appears to offer promising prospects for future research. Such endeavors aim to mitigate the impacts of drought stress.