Managing Phosphorus Availability from Organic and Inorganic Sources for Optimum Wheat Production in Calcareous Soils

Abstract

In calcareous soils, wheat productivity is much lower due to improper nutrient management, especially phosphorus (P). Therefore, this study was conducted to manage P availability from various organic (Control, FYM and Sugar cane straw applied at the rate of 10 ton ha−1) and inorganic (Control, 100% rock phosphate (RP), 50% acidulated RP, 100% acidulated RP, single super phosphate (SSP) and diammonium phosphate (DAP)) sources applied at the rate of 90 kg P2O5 ha−1 in calcareous soil while using wheat as test crop. When averaged across the organic sources, SSP performed better in emergence m−2 (126), tillers m−2 (431), spikes m−2 (419), grains spikes−1 (61), plant height (95.1 cm), 1000-GW (40 g), biological yield (11,023 kg ha−1), grain yield (4022 kg ha−1), phosphorus use efficiency (10.5%), phosphorus in leaves at tillering (2.63 mg kg−1) and anthesis stage (2.50 mg kg−1), soil P at heading (1.73 mg kg−1) and post-harvest stage (1.56 mg kg−1) compared to the rest of the mineral sources. Similarly, among the organic sources, FYM performed better than others for all tested traits. Integration of inorganic P sources with organic manures further improved crop performance and post-harvest soil P content. Therefore, using 10 tons FYM ha−1 in integration to SSP or 100% acidulated RP at the rate of 90 kg P2O5 ha−1 is recommended for ensuring optimum wheat productivity under calcareous soils.