An experiment was carried out on green synthesis of iron (Fe) and zinc (Zn) nanoparticles (NPs) at Green Nanotechnology Laboratory, University of Agricultural Sciences, Dharwad. The Fe and Zn NPs were biosynthesized using neem leaf extract and characterized through UV-Visible Spectrophotometer, Particle Size Analyzer, Scanning Electron Microscope and X-Ray Diffraction. The green synthesized Fe NPs showed maximum peak at 294 nm and Zn NPs peaked at 365 nm. The average size of Fe and Zn NPs was found to be 51.7 and 48.7 nm, respectively. SEM images showed that both biosynthesized Fe and Zn NPs were spherical in shape. XRD proved amorphous and crystalline nature of iron and zinc nanoparticles, respectively. After synthesis and characterization of NPs, lab experiment was conducted to standardize the concentration of green synthesized Fe and Zn NPs. In a lab experiment (CRD, three replications), seed priming (SP) with Fe NPs @ 200 ppm, Zn NPs @ 500 ppm and combined Fe and Zn NPs @ 400 ppm each significantly improved germination, root length, shoot length and seedling vigour index compared to the control. A pot experiment (CRD, three replications) at IABT, Dharwad, revealed that foliar spraying (FS) of Fe NPs @ 400 ppm, Zn NPs @ 500 ppm and combined Fe and Zn NPs @ 400 ppm at panicle initiation and flowering stages was optimal. The standardized optimum concentration under lab and controlled condition were further studied under field condition and it was compared with conventional fertilizers. The field study was conducted in MARS, Dharwad, Karnataka, during rabi 2023-24. The experiment was laid out in RCBD with three replications comprising of fourteen treatments. Results revealed that, SP with Fe and Zn NPs @ 400 ppm each followed by FS with Fe and Zn NPs @ 400 ppm each recorded significantly higher grain yield (44.78 q ha-1), panicle length (23.69 cm), panicle weight (103.53 g), 1000-grain weight (37.57 g), grain Fe and Zn content (39.78 and 29.06 mg kg-1, respectively), gross returns (`1,54,785 ha-1), net returns (`1,09,353 ha-1) and B-C ratio (3.41) as compared to RDF alone.