Effect of phosphorus management practices on soil properties and their correlation with wheat productivity in an acid alfisol of northwest Himalayas

Phosphorus (P) deficiency and soil degradation due to excessive reliance on inorganic fertilizers are major constraints in sustaining wheat productivity and soil fertility in acid soils. Phosphate-rich organic manure (PROM), a bio-processed organic fertilizer enriched with rock phosphate, offers a sustainable alternative by improving P availability and enhancing soil health. A two-year field study was conducted on wheat in an acid Alfisol to evaluate the effect of integrated phosphorus management on wheat yield and soil physico-chemical properties. The experiment included nine treatments: T₁: Farmer’s practice, T₂: 100% NPK, T₃:100% NPK + Lime @ 6t ha⁻¹, T₄: 100% NPK + 10t FYM ha⁻¹, T₅: 0.5t <i>Ghan jeevamrit</i> ha⁻¹ + <i>Jeevamrit</i> Sprays at 21 days interval (Natural Farming), T₆: 100% NK + 3t PROM ha⁻¹, T₇: 100% NK + 75% <i>p</i> + 0.75t PROM ha⁻¹, T₈: 100% NK + 50% <i>p</i> + 1.5t PROM ha⁻¹ and T₉: 100% NK + 25% <i>p</i> + 2.25t PROM ha⁻¹. Among the treatments, T₈ significantly enhanced wheat grain yield (4.5 t ha⁻¹) and straw yield (6.8 t ha⁻¹) over the sole application of either chemical fertilizers or PROM. This treatment also improved soil fertility status with the highest available N (293 kg ha⁻¹), P (33.2 kg ha⁻¹), and K (219 kg ha⁻¹), significantly increased water holding capacity, soil organic carbon, cation exchange capacity, exchangeable Ca and Mg. The study concludes that integrating PROM with chemical P fertilizers optimizes wheat productivity while enhancing soil health, offering a sustainable phosphorus management strategy for acid soils.