Improving rice productivity and profitability through efficient use of nitrogen and phosphorus fertilizers

Fertilizer source effects on rice growth and yield

Abstract

Nitrogen (N) and phosphorus (P) are essential for rice production, and diammonium phosphate (DAP), which supplies both N and P may provide agronomic and environmental advantages relative to urea. We evaluated seven fertilization strategies in BRRI dhan49: control (T₁), urea at N rate but no P (T₂), DAP at the N rate (T₃), urea at N rate + TSP at P rate (T₄), DAP at the P rate (T₅), no N and no P (T₆), and DAP at P rate + urea at N rate (T₇). Treatments were assessed for growth, yield, nutrient uptake, and post-harvest soil fertility. Fertilization significantly affected all parameters. T₇ produced the highest plant height (94.7 cm) and grain yield (5.65 t ha⁻¹), followed by T₄ (93.9 cm; 5.12 t ha⁻¹). Relative to the control, T₇ increased grain yield by 41% and total plant N uptake by ~75%, and it delivered the highest values for key yield components (panicle length, tillers hill⁻¹, and filled grains panicle⁻¹). Post-harvest soils under T₇ and T₄ showed elevated organic C, total N, and available P, indicating improved fertility. Profitability analysis identified T₇ as the most lucrative fertilized option (net return 5.08 × 10⁶ Tk ha⁻¹) and T₅ as the most cost-efficient (BCR 3,825) due to minimal input cost. Collectively, a regimen combining basal DAP with split urea applications enhances yield, nutrient uptake, and soil fertility while maintaining strong economic performance in BRRI dhan49.

Ann. Bangladesh Agric. 29(2): 157-174