Increasing the Use Efficiency of Fertilizer Phosphorus for Maize in Low-P Ganges Delta Soils

The availability and use efficiency of phosphorus (P) is low in the acidic Ganges delta floodplain soils. The aim of the present study was to increase the use efficiency of P by varying the methods and forms of P application. The experiment comprised a factorial combination of two methods (broadcasting and furrow placement) and two forms (granular and powder) with three rates of P fertilizer application (36, 48 and 60 kg P ha(-1)). Results showed that furrow placement of P application gave 10%-20% yield benefit over broadcasting method. Agronomic P use efficiency, partial factor productivity, economic efficiency and leaf P concentration were remarkably higher in furrow placement of P fertilizer than conventional broadcasting method. Numerically the application of powder form P fertilizer demonstrated higher yield compared to granular form of P application. The furrow placement of P fertilizer exhibited the higher yield at lower rate of P application (36-48 kg P ha(-1)) while opposite trends were observed for broadcasting. Thus, it is concluded that furrow placement of P fertilizer application at 36-48 kg ha(-1)would give the best grain yield of maize in the Ganges delta floodplain soils.