Speaker
Description
Iron (Fe) and manganese (Mn) are essential micronutrients for soybean growth, playing critical roles in chlorophyll biosynthesis, photosynthesis, enzyme activation, and antioxidant defense. However, limited availability of these nutrients in soil often reduces the effectiveness of conventional fertilizers. Foliar application provides a direct and efficient route for nutrient delivery, while nano fertilizers have emerged as promising alternatives due to their high surface area, enhanced plant uptake, and controlled nutrient release. This study investigates the foliar application of Mn₃O₄, Fe₃O₄, and MnFe₂O₄ nanoparticles (15–30 nm) throughout the complete life cycle of soybean plants. The nanoparticles were comprehensively characterized using X-ray diffraction (XRD), dynamic light scattering (DLS), UV–Visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and synchrotron-based X-ray techniques at the Cornell High Energy Synchrotron Source (CHESS) to confirm their physicochemical properties and in plant distribution. Plant physiological performance was evaluated using SPAD chlorophyll measurements and LI-COR gas exchange analysis, while elemental uptake was quantified by elemental analysis. The effects of nanoparticle treatments on chlorophyll content, photosynthesis, stomatal conductance, protein accumulation, elemental uptake, and antioxidant enzyme activities (SOD, APX, and CAT) were compared with conventional Fe and Mn salts. This integrated physiological, biochemical, elemental, and synchrotron imaging approach provides a comprehensive evaluation of Fe- and Mn-based nano fertilizers as sustainable strategies to enhance soybean productivity, nutritional quality, and resilience to environmental stress.