Phosphorus (P) and potassium (K) are essential nutrients for maize growth and productivity, but their imbalanced application limits yield and soil fertility in Nepalese mid-hills. This study evaluated the interactive effects of P and K on maize yield, physiological responses, and residual soil nutrients to develop site-specific nutrient management strategies. The experiment was conducted in Kaski District, using a split-plot design with four P levels (0, 50, 100, and 150 kg P 2 O 5 ha −1 ) as main plots and three K levels (0, 25, and 50 kg K 2 O ha −1 ) as subplots, replicated three times. Maize variety Rampur Hybrid-10 was grown under standard crop management practices. Growth, yield components, tissue P and K content, and post-harvest soil-fertility were measured. Results showed that P significantly increased grain yield, biomass, straw yield, and thousand-grain weight, with the highest grain yield (5,820 kg ha −1 ) at 150 kg P 2 O 5 ha −1 . K also improved grain yield, with maximum yield (5,430 kg ha −1 ) at 50 kg K 2 O ha −1 . A synergistic effect was observed under combined P150 × K50, resulting in 6,120 kg ha −1 grain yield. Tissue nutrient analysis confirmed enhanced P and K uptake with balanced fertilization. Residual soil P and K increased under higher P and K applications, while soil pH and organic matter remained stable. The study demonstrates that balanced P and K management improves maize productivity and supports soil fertility. Site-specific nutrient application can reduce yield gaps and promote sustainable maize production in Nepal. Long-term trials are recommended to validate these findings across diverse environmental conditions. This study is based on original field experimentation and laboratory analysis conducted under Nepalese mid-hill agroecosystem conditions.
Nepali et al. (Wed,) studied this question.