Phosphorus Spraying to Enhance Wheat Productivity in Desert Areas (Triticum aestivum L.)

Background: Wheat (Triticum aestivum L.) is a predominant staple food across the globe, supplying approximately 50% of daily calories in several countries based on its high proteins, starches, fibers, carbohydrates, vitamins and mineral contents. The study aimed to investigate the role and application method of phosphorus fertilizer and its impact on the growth and yield traits of two wheat cultivars (Baghdad and Babel) grown under desert conditions (Triticum aestivum L.). Methods: A field trial was implemented in the Al-Lehais region, located approximately 125 km west of the Basra Governorate Center, during the 2023-24 and 2024-25 growing seasons. Phosphate fertilizer was applied in three ways: soil application, foliar spray and a combination of soil application and foliar spray. Mono-ammonium phosphate (MAP 62% P2O5) fertilizer was applied at four levels: (0, 30, 60 and 90 kg P/ha for soil application and mixed application with foliar spraying and (0, 10, 20 and 30) kg P/ha for foliar spraying. For soil application, half the fertilizer was applied at planting and the other half was as a foliar spray in two equal doses during the elongation and flowering stages. For foliar spraying, the fertilizer dose was divided into three equal doses applied during the tillering, elongation and flowering stages. The crop growth rate from elongation to full maturity, total plant dry weight, phosphorus uptake at full maturity and fertilizer use efficiency were studied. Result: The results showed significant differences in the studied traits (crop growth rate, dry weight, amount of phosphorus absorbed, phosphorus utilization efficiency and grain yield) among the application methods. The foliar application method was superior to the other application methods, even though the amount applied by spraying was only one-third of the amount applied by soil application and the combined soil and spray application methods. Increasing phosphorus levels generally improved growth parameters and most measured traits. The Baghdad cultivar exhibited superior performance across all growth parameters and application methods.