Enhanced water productivity and economic returns through cropping system management: a comparative field assessment of early sown wheat-cotton versus conventional wheat–maize rotation in Egypt

Diminishing water availability necessitates re-evaluation of established agricultural methodologies, including adjustments to sowing timelines and cropping system design. A 2-year field experiment (2019–2021) with three replications compared to two cropping systems: (1) early wheat sowing (October 15) followed by cotton, and (2) conventional wheat sowing (November 15) followed by maize. The experiment was conducted in Fayoum Governorate, Egypt, using two bread wheat varieties (Misr 1 and Sakha 94). Early sowing reduced wheat grain yield by 10.7% (2.8 vs. 3.1 ton/fed; p < 0.01) and straw yield by 22.2% (2.63 vs. 3.38 ton/fed; p < 0.05) compared with conventional sowing. However, early wheat enabled a high-value cotton rotation, increasing system net returns by 212% (36,885 vs. 15,038 L.E./fed; p < 0.001) and water productivity by 134% (5.655 vs. 2.385 L.E./m 3 ; p < 0.001). The benefit-cost (B:C) ratio was 2.30 for the early wheat-cotton rotation and 1.62 for the conventional wheat–maize rotation. This demonstrates trade-offs between wheat yield and rotational profitability, establishing early sowing as a context-specific strategy for water-scarce regions with conditions similar to those investigated (clay soils, winter temperatures 12–22 °C, cotton-suitable thermal regimes). However, these findings are site-specific and require validation across locations, soil types, and climatic conditions before generalization. Enhancing water utilization efficacy and agricultural output through modified sowing schedules: a case examination of premature wheat planting