AGRONOMIC EFFICIENCY AND PROFITABILITY OF P-FERTILIZERS APPLIED AT DIFFERENT PLANTING DENSITIES OF MAIZE IN NORTHWEST PAKISTAN

The use of appropriate source of phosphorus (P) fertilizer at different planting densities has considerable impact on growth, grain yield as well as profitability of maize (Zea mays L). Field experiment was conducted in order to investigate the impact of P sources [(S0 = P not applied, S1 = SSP (single super phosphate) S2 = NP (nitrophos), and S3 = DAP (diammonium phosphate)] on maize growth analysis, yield and economic returns planted at different planting densities (D1 = 40,000, D2 = 60,000, D3 = 80,000, and D4 = 100,000 plants ha−1) at the New Developmental Agricultural Research Farm of Khyber Pakhtunkhwa Agricultural University, Peshawar, Pakistan, during summer 2006. This paper reports the profitability data with two objectives: 1) to compare agronomic efficiency and profitability of P-fertilizers, and 2) to know whether plant densities affect agronomic efficiency and profitability of P-fertilizers. Application of DAP and SSP resulted in higher partial factor productivity (PFP) (63.58 and 61.92 kg grains kg−1 P), agronomic efficiency (AE) (13.01 and 13.71 kg grains kg−1 P) and net returns (NR) (Rs. 16,289 and 16,204 ha−1), respectively, while NP stood at the bottom in the ranking with lower PFP (57.16 kg grains kg−1 P), AE (8.94 kg grains kg−1 P) and NR (Rs. 4,472 ha−1). Among the plant densities, D3 stood first with maximum PFP (69.60 kg grains kg−1 P), AE (18.21 kg grains kg−1 P) and NR (Rs. 21,461 ha−1) as compared to other plant densities. In conclusion, the findings suggest that growing maize at D3 applied with either SSP or DAP is more profitable in the wheat-maize cropping system in the study area.