Amanullah, M. Asif and L.K. Almas. 2012. Agronomic efficiency and profitability of P-fertilizers applied at different planting densities of maize in Northwest Pakistan. Journal of Plant Nutrition. 35: 331-341.
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.
Nitrogen Rates and Sources Affect Yield and Profitability of Maize in Pakistan
Nitrogen is one of the most important factors affecting maize yield and profitability. To investigate the impact of N fertilizer sources (urea, calcium ammonium nitrate [CAN] and ammonium sulfate [AS]) applied in various amounts (0, 50, 100, 150, and 200 kg N ha-1) on grain yield and profitability of maize genotypes, local cultivars (Azam and Jalal) versus hybrid (Pioneer-3025) field experiments
were done during summer 2008–09 (Year 1) and 2009–10 (Year 2). The N yielded 41 and 26% more grain than the check in Year 1 and Year 2, respectively. In both years, grain yield increased in response to the increase in N application. Application of CAN and AS resulted in more grain yield than urea in Year 1, while no differences in yield were observed in Year 2. The hybrid (P-3025) yielded 30 and 24% more grain than the average of local cultivars in Years 1 and 2, respectively. In Year 1, the net returns (NR) of PKR16262 ha-1 (one US$ = 95 Pakistani Rupees) was obtained with CAN but value cost ratio (VCR) of 3.7 was noticed with urea; in Year 2, both NR (PKR14271 ha-1) and VCR (3.1) was greatest with urea. In both years, the greatest NR was obtained with 100 and 150 kg N ha-1. Application of urea at 150 and 200 kg N ha-1, CAN at 100 and 150 kg N ha-1, and AS at 50 and 100 kg N ha-1 was economical in terms of NR in both years.
Influence of Organic and Inorganic Nitrogen on Grain Yield and Yield Components of Hybrid Rice in Northwestern Pakistan
Field experiments were conducted to assess the impact of various organic sources, inorganic
nitrogen (N) and the different combinations of inorganic N (urea) + organic source on the yield
components (YC) and grain yield (GY) of hybrid rice (Oryza sativa L., Pukhraj) under rice-wheat system. The experiments were conducted at Batkhela (Malakand), Northwestern Pakistan, in 2011 and 2012. Our results revealed that YC and GY ranked first for the hybrid rice when applied with sole inorganic N (urea), followed by the application of N in mixture (urea + organic sources), while the control plots (no N applied) ranked in the bottom. Among the six organic sources (three animal manures: poultry, sheep and cattle; three crop residues: onion, berseem and wheat), application of N in the form of poultry manure was superior in terms of higher YC and GY. When applying 120 kg/hm2 N source, 75% N from urea + 25% N from organic source resulted in higher YC and GY in 2011, while applying 50% N from urea + 50% N from organic sources caused higher YC and GY in 2012. Therefore, the combined application of N sources in the form of urea + organic source can produce good performances in terms of higher YC and GY of rice under rice-wheat cropping system.
Prof. Dr. Amanullah