Effect of different concentrations of iron and zinc nanoparticles on the growth and yield of groundnut (Arachis hypogaea L.)

Groundnut (Arachis hypogaea L.) is an important legume crop cultivated for its oil and protein content and widely used for human consumption and animal feed. However, its productivity is often limited by micronutrient deficiencies, particularly zinc (Zn) and iron (Fe), especially in calcareous soils. This investigation was conducted to determine the effect of foliar application of zinc and iron nanoparticles on the growth and yield of groundnut to identify the optimal concentration under field conditions. A field experiment was conducted at the Bangladesh Institute of Nuclear Agriculture (BINA), Sub-station Sunamganj, following a randomised complete block design (RCBD) with 17 treatments and 3 replications. The treatments consisted of different concentrations and combinations of Zn and Fe nanoparticles applied as foliar sprays. Growth parameters and yield attributes were recorded and analysed statistically. The results showed that foliar application of Zn and Fe nanoparticles significantly influenced growth and yield parameters. The combined treatment Zn100 + Fe50 mg L-1 (T8) produced the highest biomass accumulation, pod number and grain yield compared to other treatments. Higher concentrations did not result in further yield improvement, indicating a concentration-dependent response. These findings suggest that moderate combined application of Zn and Fe nanoparticles may enhance growth and yield performance of groundnut under the tested conditions. Further studies incorporating detailed soil and nanoparticle characterisation are recommended to strengthen mechanistic understanding.