Optimization of NPK fertilization for sustainable production of Durum Wheat (Triticum durum Desf.) in the Setif region, Algeria

This study aimed to optimize nitrogen, phosphorus, and potassium fertilization for sustainable production of durum wheat (Triticum durum Desf.) in the semi-arid region of Setif, Algeria. The experiment was conducted during the 2022–2023 growing season on a clayey soil characterized by low organic matter content (3%), slightly calcareous conditions (2.26% CaCO₃), and alkaline pH (8.12). A randomized block design with a single factor consisting of six fertilization treatments was adopted to evaluate the effects of NPK fertilization. Each block was divided into six elementary plots measuring 10×1.3 m (13 m²). Soil moisture, physiological traits (leaf area, chlorophyll content, and canopy cover), and agronomic parameters (plant and tiller density) were monitored throughout the crop cycle. Data were analyzed using analysis of variance and correlation analysis. The results showed that fertilization had no significant effect on soil moisture at most sampling dates, except at the final sampling date, where significant differences were observed. Fertilized treatments showed higher soil moisture compared with the unfertilized control. Fertilizer applications significantly influenced vegetative cover, chlorophyll content, and leaf area, whereas plant density and tiller density were not significantly affected. The highest vegetative cover was obtained with treatment T4 (32.86%), while treatment T3 produced the largest leaf area. Correlation analysis revealed a strong positive relationship between soil moisture and chlorophyll content (r = 0.972), indicating the importance of water availability for crop physiological performance. These findings highlight the importance of optimized NPK fertilization for improving durum wheat performance under semi-arid conditions in the Setif region.