Response of maize to diammonium phosphate and farmyard manure application on three different soils.

摘要

Efficiency of phosphorus applied to correct its wide spread deficiency is very low. An important strategy to improve the efficiency of applied P is the combined application of organic and inorganic sources of phosphorus. A pot experiment was set up to investigate the effect of either alone or combined application of FYM and DAP on maize, grown in three different calcareous soils. The four treatments viz; control, DAP, FYM and DAP+FYM were arranged in factorial set up using completely randomized design (CRD). Diammonium phosphate was applied to supply 80 mg P₂O₅ per kg soil while farmyard manure was added at 50 g pot-1. Maize (cv. Pak Hybrid-7222) was used as test crop. Shoot dry matter of plants and P uptake were recorded. Physiological and agronomic P efficiencies and apparent P recovery were computed. Results regarding effect of combined P sources on yield parameters (shoot dry matter=21.82 g/pot for DAP+FYM, 17.28 g/pot for FYM and 17.76 g/pot for DAP) and various P efficiencies were significantly better (agronomic efficiency 21.27 g/g for DAP+FYM for FYM 9.91 g/g and 11.13 g/g for DAP) than organic or inorganic P sources alone.