Combined Effects of Nitrogen, Phosphorus, and Potassium on Maize Growth, Development, and Yield

An experiment was conducted to evaluate the combined effects of nitrogen (N), phosphorus (P), and potassium (K) on maize growth, development, and yield. Plant height, leaf area per plant, number of cobs per plant, number of grains per plant, 100-grain weight, stem diameter, green fodder yield, and harvest index were significantly influenced by increasing NPK levels. The minimum plant height (84.02 cm), leaf area (121.00 cm²), number of cobs per plant (0.88), number of grains per plant (300.20), 100-grain weight (220.10 g), stem diameter (2.51 cm), green fodder yield (3.89 t ha⁻¹), and harvest index (18.10%) were recorded in the control treatment. The highest values for most growth and yield parameters were observed in the highest NPK treatments, with plant height reaching 208.00 cm, leaf area 207.10 cm², number of cobs 1.27, number of grains 514.77, 100-grain weight 328.10 g, stem diameter 3.55 cm, green fodder yield 6.05 t ha⁻¹, and harvest index 35.80%. These results indicate that balanced and increased NPK fertilization significantly enhances vegetative growth, reproductive development, biomass accumulation, and yield in maize by improving nutrient availability, photosynthetic capacity, and assimilate partitioning.