Impact of cultivars, nitrogen rates, and sugar beet processing by-product on wheat growth and yield

The wheat production management in the newly reclaimed soils requires innovative approaches that combine organic amendments with traditional fertilization methods. This research examined the combined effects of sugar beet filter cake (BFC) (without treating and 24 t ha⁻¹) and mineral nitrogen fertilization rates (60, 120, 180, and 240 kg N ha⁻¹) on the agronomic performance and yield components of three bread wheat cultivars (Sakha 95, Misr 3, and Sids 14) in the newly reclaimed calcareous soils across two growing seasons (2021/2022 and 2022/2023). A split-plot design with three replications assessed ten essential agronomic traits. Analysis of variance indicated significant seasonal effects (p ≤ 0.05) on physiological traits, with SPAD values declining from 40.92 to 25.61 across seasons. Fertilization treatments were the most significant factor, demonstrating highly significant effects (p ≤ 0.001) on 90% of the assessed parameters. Cultivar Sakha 95 exhibited enhanced grain yield (7.47 t ha¹) and harvest index (38.34%), whereas Sids 14 showed optimal morphological characteristics, including maximum plant height (114.15 cm) and flag leaf area (43.43 cm²). Combining BFC with 240 kg N ha⁻¹ resulted in the highest grain yield (8.48 t ha⁻¹) and spikes per square meter (340.61), indicating increases of 52.5% and 28.9% compared to the lowest nitrogen rate, respectively. Path coefficient analysis revealed that biological yield and harvest index are the main determinants of yield, with coefficients of 0.813*** and 0.614***, respectively. Principal component analysis accounted for 93.81% of the total variation (PC1 = 80.15%, PC2 = 13.66%), indicating clear clustering patterns between organic and non-organic fertilization regimes. The findings offer insights into optimizing integrated nutrient management strategies to enhance wheat productivity in newly reclaimed soils.