Assessing agronomic response of wheat to raised bed, furrow irrigation, and partial root zone drying under variable water regimes

Water scarcity in arid and semi-arid regions pose serious challenges to sustainable agriculture. Effective water management strategies are therefore required to improve crop productivity and water-use efficiency (WUE). This study evaluated the combined effects of irrigation methods, irrigation volumes, and partial root zone drying irrigation (PRDI) on wheat yield, agronomic traits, and WUE. Field experiments were conducted during two cropping seasons (2021–22 and 2022–23) at a farmer’s field in Kandiaro, Sindh, Pakistan. Treatments comprised two irrigation methods (ridge-furrow and raised bed-furrow), two irrigation modes (conventional irrigation and PRDI), and three irrigation volumes (100%, 80%, and 50% ETc), resulting in 12 treatment combinations, each replicated three times. Ridge and furrow widths were maintained at 0.60 and 0.30 m, respectively, while raised-bed width was 0.60 m and ridge/bed and furrow lengths were 5.40 m. Significant differences (p < 0.05) were observed in wheat yield, agronomic traits, and WUE among irrigation methods, volumes, and irrigation modes. Treatments T7 (raised bed + PRDI + 100% ETc) and T10 (furrow + PRDI + 100% ETc) showed the most favorable balance between grain yield and WUE. Although T1 produced the highest values for several agronomic traits, T7 and T10 were identified as the overall optimal treatments. T6 (furrow + PRDI + 50% ETc) achieved the highest WUE among deficit treatments but resulted in considerable reductions in grain yield and biomass. The findings demonstrate that integrating PRDI with raised bed or furrow irrigation can improve water productivity while sustaining wheat yield in arid and semi-arid regions.