Effect of Long-term Continuous STCR based Fertilization on Potassium Pools and Balance in Calcareous Soil under Rice based Cropping System

Potassium (K) is essential for soil, plant and human nutrition. In calcareous soils, high Ca levels suppress the K uptake by crops therefore, growing in these soils often require above normal of fertilization satisfactory growth. Therefore, a long-term experiment was started soil (medium available K) replicated thrice randomized block design with rice-based cropping system nine treatments [T1- control, T2-FP, T3-GRD, T4-YT 35q/ha, T5-YT 40 q/ha, T6-YT 45 T7-STCR (YT 35 q/ha) + IPNS, T8-STCR 40q/ha) T9-STCR +IPNS at Experimental Farm, RPCAU, Pusa, Samastipur, Bihar, India during kharif-2019. Continuous addition STCR based fertilizer along 5 tons ha-1 compost improved organic carbon, CEC, potassium status balance whereas control unfertilized decreased most, results unsustainable yields fertility. Treatment T9 rice superior over all other fractions, chemical properties surface (0-15 cm) sub-surface (15-30 cm).