Abstract
Phosphorus (P) use efficiency is very low (5 to 25%) due to fixation with Ca+2/Mg+2 in alkaline/calcareous soils which
decreases P availability for plant uptake. There is need to improve P availability for plant growth. For this purpose, coating of
phosphatic fertilizer with the organic polymer may reduce P fixation and cause the steady release of P to increase its use
efficiency. This study accesses enhanced phosphorus use efficiency along with improved growth of wheat at different rates of
polymer coated di-ammonium phosphate (DAP) in comparison with uncoated DAP. In laboratory experiments, release pattern
of P in soil from different coating concentrations (0, 0.5, 1.0, 1.5%) and number of coatings (uncoated, single, double, triple)
were tested under controlled conditions. The best screened polymer concentration (1%) and coating layers (double coating)
were tested under field conditions on wheat crop growth, yield and fertilizer efficiency. Results showed that application of
100% of recommended rate of P as polymer coated DAP increased plant height (4%), biological yield (39%), grain yield
(29%), agronomic efficiency (58%), recovery efficiency (130%) and nitrogen, phosphorus and potassium contents of wheat
grain and straw was also increased compared to uncoated DAP. These results revealed that polymer coated DAP can be proved
more effective fertilizer to improve growth, yield and phosphorus use efficiency of the wheat crop over commercial DAP.
