Interactive Effects Of Irrigation Deficit And Foliar Npk Fertilization On Wheat Performance And Soil Dynamics In Water-Limited Environments

This study evaluated the combined effects of irrigation depletion levels and fertilization treatments on wheat (Triticum aestivum L.) yield, nutrient uptake, soil chemical properties, and irrigation water productivity under field conditions in Northern Egypt. A split-plot design with three replicates was implemented over two winter seasons (2022/2023 and 2023/2024) at Qarada Research Station. The main factors comprised two irrigation regimes defined by 50% (I1) and 75% (I2) depletion of available soil moisture. Subplots involved four fertilization treatments: (F1: soil- applied fertilizers as a recommended NPK application (control), F2: F1 + foliar application of NPK (20:20:20) F3: foliar NPK (20:20:20) + supplementary fertilizers, and F4: supplementary soil fertilization only. Results demonstrated a significant interaction between irrigation and fertilization strategies.The I1F2 treatment yielded the highest grain production (3.55 t/fed) and enhanced nutrient assimilation and biomass accumulation. In contrast, the I2F2 treatment exhibited superior irrigation water productivity (up to 2.05 kg m-3), indicating improved irrigation water productivity with a slight yield reduction. Moderate irrigation combined with balanced fertilization improved soil nutrient status and organic matter content, while reduced irrigation and fertilization increased soil salinity. These findings highlight a critical balance between maximizing yield and conserving water resources.The integration of moderate irrigation with foliar and soil NPK fertilization represents a viable strategy to optimize wheat productivity and sustainability under water-limited conditions prevalent in Northern Egypt.