Optimizing furrow irrigation performance with WinSRFR software through field experiments and simulations in sunflower...

Surface irrigation continues to dominate agricultural practices in India; however, its effectiveness is often limited by deep percolation losses and non-uniform water distribution. This study, conducted during 2023-2024 and 2024-2025 at ICAR-CIAE, Bhopal, India aimed to evaluate and optimize furrow irrigation methods for sunflower cultivation using WinSRFR simulation software. Continuous Furrow Irrigation (CFI) and Alternate Furrow Irrigation (AFI) were tested under varying furrow lengths (45, 55, 65 m) and inflow rates (1.0, 1.5, 2.0 lps) across three crop growth stages. Field data on infiltration, advance and recession times, and soil moisture were collected and used to calibrate the model. Simulation results revealed that AFI with a 65 m furrow length, 1.0 lps flow rate, and 80-min cutoff time achieved the highest performance: 87% Application Efficiency (AE), 91% Distribution Uniformity (DU_lq), and only 15% Deep Percolation (DP). In contrast, CFI under optimal conditions (1.1 l ps, 64.4 min) reached 71% AE. Model validation showed high agreement with observed values (R² > 0.93, RMSE < 1.4%, p < 0.001). Sensitivity analysis identified inflow rate and cutoff time as the most influential variables. Cross-season validation confirmed the robustness of optimized parameters under real field conditions. These findings offer practical, scalable recommendations for improving water productivity in Indian furrow irrigation systems using simulation-assisted planning.