Study on changes in the physiological growth characteristics and yield-increasing effects of winter wheat under water-fertilizer-pesticide synergistic regulation.

Introduction: Against the backdrop of global climate change and resource constraints, the extensive management of water, fertilizer, and pesticide resources has exacerbated non-point source pollution in farmland. The patterns of crop pests and diseases are becoming increasingly complex, and relying solely on chemical control methods is insufficient to meet the demands of sustainable pest management. This has led to constraints on crop growth and a significant decline in yields. To promote the transition of crop protection practices toward a green and sustainable model, this study conducted field trials on water-fertilizer-pesticide synergistic regulation (WFPSR) in the North China Plain from 2023-2025. Methods: Four reduced-rate application levels were set (R1: 14%, R2: 33%, R3: 53%, R4: 73%), two real-time irrigation levels (W1: 80% θ Results and discussion: Appropriate WFPSR significantly promoted the physiological growth of winter wheat, with the W1R2 treatment yielding the best results. Compared to CK, the SPAD, Pn, and LAI values of the W1R2 treatment increased by 17.3%, 11.3%, and 7.84%, respectively. The Logistic model fit well, with R² values all exceeding 0.95. PCA-based dimensionality reduction and yield fitting models indicated that the W1R2 treatment increased yields by improving crop physiological functions, thereby increasing thousand-kernel weight and the number of grains per spike. With yield, water and fertilizer savings, and pesticide savings increasing by 8.2%, 40.2%, and 33%, respectively, compared to CK. In summary, the WFPSR model based on the W1R2 combination provides a theoretical foundation for the integrated management of green yield increases in winter wheat on the North China Plain.