Harnessing Genetic Diversity and Precision Nutrient Management for Nutrient-Dense, Climate-Resilient Durum Wheat (Triticum turgidum L. var. durum) in a System-Level Approach

Durum wheat (Triticum turgidum L. var. durum) plays a central role in global food and nutritional security, yet its grain mineral and protein quality remain highly variable across varieties and environments. This study aimed to evaluate the combined effects of varieties, nitrogen (N) fertilization, foliar zinc (Zn) and sulfur (S) application, and seasonal variation on grain macro- and micronutrients (Ca, Mg, K, Zn) and protein content, adopting a system-level approach that integrates varieties, nutrient management, and seasonal variability. We hypothesized that aligning variety selection with precision nutrient management would improve grain nutritional quality while enhancing resilience to environmental variation. Significant differences among varieties (p < 0.05) were observed, with the spring-sown variety Durablank exhibiting the highest grain Zn concentration (34.70 mg kg−1) compared with MV Pelsodur (23.0 mg kg−1) and GK Julidur (23.8 mg kg−1), representing a 50.87% varietal difference. Grain Ca, Mg, and K varied widely across varieties and seasons, with drought in 2022 increasing grain Zn, while the wetter 2023 season enhanced Mg and K accumulation. A clear yield–protein trade-off was found, where high-yielding MV Pelsodur maintained 14.3% protein while moderate-yielding Durablank reached 16.8%. Foliar Zn and S applications significantly increased grain Zn, particularly in Zn-efficient varieties. Nitrogen fertilization at 100 kg ha−1 improved macronutrient accumulation by 12–20% compared with 60 kg N ha−1. Significant varieties × N × season interactions (p < 0.01) highlight the need for adjusted varieties -specific nutrient management strategies. Overall, the findings demonstrate that integrating genetic selection with optimized fertilization and season-responsive management practices may contribute to improving grain nutritional quality of durum wheat.