Energy Assessment in Rabi Sunflower under Varying Drip Irrigation Regimes and Fertigation Levels

Efficient Irrigation and Nutrient Management Strategies are Important for Sustainability of Agriculture. In order to elucidate the above hypothesis, an on-farm experiment was carried out at Water Technology Centre, PJTSAU, Hyderabad to study the effect of different combinations of drip irrigation regimes and fertigation levels on energy dynamics under Rabi sunflower. The experimental design was split-plot design and contained three replications for DRSH-1 sunflower variety. Three treatments of drip irrigation were compared as main plots (0.8 Epan, 1.0 Epan and 1.2 Epan base values of the Epan pan) and four levels of fertigation at the sub-plots (60%, 80%, 100% and 120% of the recommended dose). 75:90:30 kg NPK ha-1 was set for the fertilizer recommendation. Energy parameters: energy output, energy efficiency, net energy gain, energy profit, and energy intensity were assessed across treatment combinations. The findings indicated that peak energy consumption transpired under settings integrating 1.2 Epan irrigation with a 120% recommended dosage of N and K₂O fertigation. The optimal irrigation level was 1.0 Epan, which produced enhanced outcomes in energy output (102.6 GJ ha-1), use efficiency (5.02), and nett energy gains (90.1 GJ ha-1) relative to lower irrigation levels. The application of the full prescribed dose in fertigation treatments proved to be excellent, exhibiting exceptional performance across all energy metrics: output (105.6 GJ ha-1), usage efficiency (8.1), nett energy (92.5 GJ ha-1), profitability (0.223), and intensiveness (0.0022). Statistical study revealed no significant interaction between irrigation and fertigation treatments, indicating that these parameters independently affect energy efficiency indicators.