To address the bottlenecks of low water and fertilizer utilization efficiency and limited yield potential inherent in Henan Province’s traditional winter wheat cultivation model of “furrow irrigation + conventional row seeding”, this study delved into the synergistic regulatory mechanisms of drip irrigation combined with wide-row precision seeding. It focused on their effects on the physiological ecology and yield-quality traits of winter wheat. A two-factor experiment, encompassing “sowing method × irrigation method” will be carried out during the 2024–2025 wheat growing season, featuring four treatments: furrow irrigation + conventional row seeding (QT), drip irrigation + conventional row seeding (DT), furrow irrigation + wide-row precision seeding (QK), and drip irrigation + wide-row precision seeding (DK). Results reveal that wide-row precision seeding optimized the canopy structure, raising the leaf area index (LAI) at the heading stage by 20.19% compared to QT, thereby enhancing ventilation and light penetration and reducing plant competition. Drip irrigation, with its precise water delivery, boosted the net photosynthetic rate of the flag leaf 35 days after flowering by 62.99% relative to QT, stabilizing root water uptake and significantly delaying leaf senescence. The combined effect of the two treatments (DK treatment) synergistically improved the canopy structure and photosynthetic performance of winter wheat, prolonging the functional period of green leaves by 29.41%. It established a highly efficient photosynthetic cycle, marked by “high stomatal conductance-low intercellular CO₂ concentration-high net photosynthetic rate”. The peak net photosynthetic rate (P_n) 13 days post-flowering rose by 23.9% compared to QT. Moreover, while reducing total water consumption by 21.4%, it substantially increased water use efficiency (WUE) and irrigation water use efficiency (IWUE) by 43.2% and 14.2%, respectively, compared to the QT control. Ultimately, the DK treatment achieved a synergistic enhancement in both yield and quality: grain yield increased by 14.7% compared to QT, wet gluten content reached 35.5%, and total protein yield per unit area rose by 13.1%. This study demonstrates that coupling drip irrigation with wide-row precision seeding is an effective strategy for achieving water-saving, high-yield, and high-quality winter wheat cultivation in the Huang-Huai-Hai region. This is achieved through the synergistic optimization of canopy structure, enhanced photosynthetic efficiency, and improved WUE. These findings provide a mechanistic basis and a scalable agronomic solution for sustainable intensification of winter wheat production under water-limited conditions in major cereal-producing regions.

To address the issues of low water and fertilizer use efficiency and limited yield potential in traditional winter wheat cultivation in Henan Province, and to determine the optimal drip irrigation frequency for wide-row precision sowing under a constant total irrigation amount, this study was conducted based on a field experiment in Zhengzhou, Henan, during the 2024–2025 season. Four treatments were set up: border irrigation with wide-row precision sowing (QK40), and single-drip irrigation events of 25 mm (DK25, high frequency), 40 mm (DK40, medium frequency), and 55 mm (DK55, low frequency). The effects of drip irrigation frequency on photosynthetic accumulation after anthesis (AUC), source–sink coordination index (SSCI), and the synergy among water, grain, and quality in wide-row precision-sown winter wheat were quantitatively analyzed. The results showed that DK25 significantly delayed leaf senescence and extended the green leaf functional period by 9 days by stabilizing moisture in the 0–40 cm root zone. Post-anthesis photosynthetic accumulation increased by 23.39% and was highly significantly positively correlated with yield. The leaf area index at the heading stage increased by 23.54%, and the source–sink coordination index (SSCI) improved by 45.1%. Over the whole growth period, water consumption was reduced by 10.38%, water use efficiency increased by 23.5%, and yield increased by 8.9%, while grain quality remained stable. Entropy Weight-TOPSIS evaluation showed that DK25 performed the best. This study can provide a cultivation pattern and technical parameters for water-saving, high-yield, and high-quality wide-row precision-sown winter wheat in the Huang-Huai-Hai Plain.