Further observations on Enhancing Soybean Performance with Green-Synthesised Silver Nanoparticles from Neem Leaves: Effects on Physicochemical Properties, and Nutritional Composition

Abstract

Plant nanotechnology provides sustainable solutions for improving crop productivity and quality. This study evaluated the effects of neem (Azadirachta indica) derived biosynthesised silver nanoparticles (AgNPs) on agromorphological traits, physicochemical properties, and nutritional characteristics of three soybean (Glycine max) genotypes from Nigeria (SOY-MNA-001, SOY-MKW-001, and SOY-MNA-002). Silver nanoparticles were synthesised using neem leaf extract and characterised by UV–Vis spectroscopy, dynamic light scattering, and scanning electron microscopy. Soybean seeds were primed with AgNPs at 0, 25, 50, 75, and 100 ppm and evaluated under field conditions using a factorial experimental design. AgNP application significantly supported growth, yield, seed quality, and oil characteristics in a dose- and genotype dependent manner. Moderate concentrations (25–50 ppm) generally promotes vegetative growth, branching, pod number, seed yield, protein, lipid, and mineral contents, while maintaining acceptable moisture and fibre levels. Improvements in oil quality were observed at optimal doses, including reduced acid and peroxide values and enhanced iodine and saponification values in responsive genotypes. Conversely, higher concentrations (75–100 ppm) induced growth suppression, nutritional trade offs, and oxidative instability in some genotypes. In general, neem derived AgNPs functioned as effective bio-stimulants at optimized concentrations, indicating their potential for sustainable soybean productivity and quality enhancement in Nigeria. Neem-derived AgNPs should be evaluated in combination with conventional fertilizers and organic amendments to develop integrated, cost-effective, and environmentally sustainable soybean production systems Future research should focus on elucidating the physiological, biochemical, and molecular mechanisms underlying AgNP-mediated improvements in growth, yield, and seed quality