Impact of seed treatment with <i>Azadirachta indica</i> based silver nanoparticles on the early growth and resistance of soybean plant under drought stress

Nanoparticles enhance plant growth and resilience to diverse environmental stressors but can also adversely affect plants.This study investigated the impact of neem-mediated silver nanoparticles (AgNPs) in seed treatment on soybean plants' early growth and resistance under drought stress.AgNPs were synthesized using a neem leaf extract reductant.Characterization of AgNPs used dynamic light scattering and SEM with EDX spectroscopy.The experiment was arranged in randomized complete block design with four replicates.The main plot was field water capacity (FWC) at 100%, 80%, 60%, and 40%, representing the level of drought stress.The subplots represented seed treatments (control, AgNP priming, and AgNP coating).Results showed that AgNPs had a z-average of 55 nm, PDI of 0.449, and zeta potential of -28.8 mV.We detected Ag, C, O, and N in the spherical AgNPs.Seed priming and coating with AgNPs reduced plant height, shoot dry weight, root dry weight, and root volume.As the level of drought stress increased, seed priming increased malondialdehyde content, while the effect of seed coating was more moderate than that of seed priming.In this study, seed treatment with AgNPs enhanced the proline content and activity of peroxidase to mitigate the adverse effects of drought stress.