Magnesium oxide nanoparticles enhance tomato growth and magnesium uptake with reduced leaching in acidic soils

Magnesium (Mg) leaching in acidic soils poses a significant challenge to sustainable agriculture. While nanotechnology offers potential solutions, the efficacy of magnesium oxide nanoparticles (MgO-NPs) in mitigating Mg loss remains poorly understood. This study investigated the effects of MgO-NPs on tomato growth and Mg migration in acidic soil using a soil column experiment, comparing them with conventional bulk MgO and MgSO₄. Our results demonstrated that MgO-NPs were the most effective treatment in reducing Mg leaching, showing a significantly lower Mg migration flux than MgSO₄ in tomatoes. Concurrently, MgO-NPs substantially increased exchangeable Mg content in the topsoil (0-20 cm) by over 113% and improved soil pH, thereby enhancing the retention of other key nutrients such as potassium and calcium. These improvements in the soil environment translated into enhanced plant performance: MgO-NPs significantly boosted chlorophyll content, photosynthetic efficiency, and mineral nutrient accumulation, which collectively led to increased plant growth and superior fruit yield and quality. In conclusion, MgO-NPs present a highly promising sustainable amendment for acidic soils, outperforming traditional Mg fertilizers by simultaneously minimizing nutrient leaching and promoting tomato productivity.