Journal of Experimental Agriculture International

A field experiment was conducted during the kharif seasons of 2023 and 2024 at the Main Agricultural Research Station, University of Agricultural Sciences, Dharwad, Karnataka, to evaluate the effect of Nano DAP on productivity and profitability of mungbean (Vigna radiata (L.) Wilczek). The experiment was laid out in a Randomized Complete Block Design with seven treatments and three replications. Treatments comprised different levels of recommended dose of phosphorus (RDP) with or without foliar application of Nano DAP at 25 and 40 days after sowing (DAS). Pooled results indicated that application of 100% RDP along with foliar spray of Nano DAP @ 2 ml L⁻¹ at 25 and 40 DAS significantly improved growth parameters, yield attributes and seed yield. The treatment recorded maximum plant height (53.8 cm), branches per plant (4.40), pods per plant (26.32), seeds per pod (11.95) and 100-seed weight (4.17 g). Consequently, the highest seed yield (1656 kg ha⁻¹) was obtained, which was significantly superior to other treatments but comparable with 100% RDP + single Nano DAP spray. Economic analysis revealed that the same treatment recorded higher gross returns (₹90,498 ha⁻¹), net returns (₹66,855 ha⁻¹) and benefit–cost ratio (4.28). The enhanced performance was attributed to improved phosphorus-use efficiency, better nutrient uptake and improved source–sink relationship under integrated soil and foliar nutrition. The study concluded that combined application of 100% RDP with Nano DAP foliar sprays at critical growth stages is an effective and economically viable strategy for enhancing mungbean productivity under rainfed conditions of the northern transition zone of Karnataka (Zone-8).