Effect of combined application of PSB with NPK fertilizers on growth and yield of maize (<i>Zea mays</i>) at Puranchaur, Kaski, Nepal

Global agriculture faces the pressing challenge of meeting the rising demand for food in a sustainable manner. Increasing crop production efficiency, particularly through the optimization of nutrient supply, is critical to addressing this issue. This research investigates an approach to enhance nutrient use efficiency, and boost crop yields. A study was conducted in Puranchaur, Pokhara Metropolitan City, Kaski, Nepal, from March 2023 to June 2023, to determine the appropriate application of chemical fertilizers, specifically urea, diammonium phosphate (DAP), and muriate of potash (MOP), in combination with a biofertilizer namely phosphate solubilizing bacteria (PSB), for the Arun-2 variety of maize. A randomized complete block design (RCBD) of seven treatments and three replications was employed in the experimental design. Significant differences among treatments were obtained through data analysis, with the highest yield of 3.92 Mt·ha⁻¹ (metric ton per hectare), and the lowest yield of 3.05 Mt·ha⁻¹ observed in the treatments recommended NPK dose (NPK at 120:80:60 kg·ha⁻¹), + PSB (T3), and Control (T1) respectively. The recommended NPK dose + PSB also had a pronounced effect on yield attributes as well as growth parameters of plants. Combined application of chemical fertilizers at the recommended rate with phosphate solubilizing bacteria was found to be the most efficient method for maximizing maize yield.