1Ph. D. Scholar, Department of Agronomy, University of Agricultural Sciences, Raichur, Karnataka, 584 128
2Direcotor of Extension, Department of Agronomy, University of Agricultural Sciences, Raichur, Karnataka, 584 128
3Assistant Professor, Department of Agronomy, University of Agricultural Sciences, Raichur, Karnataka, 584 128
4Professor, Department of Agronomy, University of Agricultural Sciences, Raichur, Karnataka, 584 128
Agricultural Research Station, University of Agricultural Sciences, Gangavathi, Raichur, Karnataka, 584 128
*Corresponding author's Email: jmgayakwad@gmail.com
Online published on 2 September, 2019.
A field experiment was conducted during the rainy (kharif) seasons of 2016 and 2017 at Gangavathi, Raichur, Karnataka, to study the effect of irrigation scheduling and fertigation on nitrogen and water-use efficiency of drip-irrigated direct-seeded rice (Oryza sativa L.) in clay soil. The experiment laid out in split-plot design with 4 irrigation scheduling based on irrigation water: cumulative pan evaporation (IW: CPE) ratios assigned to main plots and 4 drip fertigation levels were allocated in subplots and replicated thrice. Irrigation scheduling at an IW: CPE ratio of 1.50 recorded significantly higher nutrient-use efficiency, viz. nitrogen (35.2 kg/kg), phosphorus (85.4 kg/kg) and potassium (102.5 kg/kg) and but lower water-use efficiency (7.69 kg/ha-mm) and water productivity (0.61 kg/m3). Among the drip fertigation levels, drip fertigation at 75% recommended dose of nitrogen (RDN) recorded higher nitrogen-use efficiency (41.5 kg/kg). Treatment of 125% RDN resulted in higher phosphorus-use efficiency and potassium-use efficiency (84.1 and 101.0%, respectively) and water-use efficiency and water productivity (7.22 kg/ha-mm and 0.59 kg/m3 respectively).
DSR, Fertigation, Nutrient-use efficiency, IWCPE ratio, Water-use efficiency
