Yield Variability Studies and Proximate Analysis of Two Varieties of Maize (Zea mays L.) Exposed to Iron Oxide Nanoparticles

A study of yield variability studies and proximate analysis of two maize varieties (Sammaz-S2 and Bida maize) was conducted at the Botanical Garden of the Department of plant Science and Biotechnology, Federal University of Lafia during the 2024 cropping season. Four concentrations of iron oxide nanoparticles (0 RPM, 20 RPM, 40 RPM, and 80 RPM) were prepared and applied as a foliar spray to maize varieties at thrice. The experiment was set in a Randomized Complete Block Design (RCBD) with three replications. Number of cobs per plant fresh and dry weight of 100 seeds were used to determine the yield variability, moisture, ash, carbohydrate, protein and protein were checked for proximate composition. The results showed, that Sammaz-S2 performed better, with increased cob numbers and improved seed traits at 20 RPM, while Bida maize showed limited response. At 40 RPM, both varieties experienced reduced productivity, indicating nanoparticle toxicity, though partial recovery at 80 RPM suggests stress adaptation. Fresh seed weight increased at 20 RPM, particularly in Bida maize, reflecting enhanced hydration, while dry weight peaked at 40 RPM, suggesting optimized nutrient storage. Proximate composition analysis showed increased ash and carbohydrate content at moderate doses but reduced moisture and fat levels with higher nanoparticle concentrations. Protein and fiber responses were based on genotype type. These findings demonstrate the potential of iron oxide nanoparticles to improve maize productivity and nutritional quality when used at optimal doses, emphasizing the importance of dose calibration to avoid toxicity.