Abstract
The efficiency of acidic phosphate fertilizer is considered better as compared to basic phosphate fertilizers in calcareous soils. Urea phosphate (UP), an acidic fertilizer (pH, 2) having 17% N and 44% P2O5 was prepared and evaluated in greenhouse studies for its effect on wheat crop (variety Sehar) in comparison to di-ammonium phosphate (DAP), a basic fertilizer with pH~ 8. The soil used for the pot experiments was a sandy clay loam and calcareous in nature. Phosphorus treatments were applied at sowing time from either source @ 0, 20, 40, 45 60 and 80 mg P2O5 kg-1 soil. Urea was applied @ 120 mg N kg-1 soil in three splits to all the pots. Both the P fertilizer sources increased wheat grain yield over control (where no P was applied); which was higher in UP (42.98 – 48.44 g pot-1 ) as compared to DAP (42.23 – 44.53 g pot-1 ). Phosphorus uptake in grain was also higher with the application of UP (138 – 161 mg P2O5 pot-1 ) as compared to DAP (134 – 145 mg P2O5 pot-1 ).In all the treatments, nitrogen percentage in grains remained almost unchanged and it ranged from 1.93 – 1.94% and 1.87 – 1.91% for UP and DAP, respectively. The results suggested that UP was a better source of P for wheat in calcareous soil.
