Cultivar-specific response to different phosphate fertilization in durum wheat

Phosphorus is critical for many physiological and metabolic processes in Triticum durum, including growth, nutrient assimilation, and photosynthesis. Although the physical mechanisms of phosphorus remobilization are well characterized, the genetic regulation of these processes and their impact on crop productivity remain comparatively underexplored. This study investigates the genotype-specific responses of two durum wheat cultivars, Ciccio and Svevo, to varying phosphorus fertilization regimes, integrating physiological, molecular, and proteomic analyses. The analyses conducted at the stem elongation stage reveal that Ciccio exhibits a strong dependence on external phosphorus inputs characterized by significant increases in plant height and pigment content under fertilized conditions, but limited root plasticity and internal phosphorus use efficiency. In contrast, Svevo demonstrates intrinsic nutrient efficiency and greater adaptability to phosphorus-deficient environments. The molecular analysis shows cultivar-specific expression patterns of key genes involved in phosphorus and nitrogen metabolism, highlighting the genetic basis for cultivar-specific responses to phosphorus availability. Proteomic profiling further supports these findings, with Svevo exhibiting dynamic regulation of proteins involved in one-carbon metabolism, hormonal signalling, and phosphate recycling. Together, these findings highlight the importance of developing cultivar-specific fertilization strategies and implementing precision agriculture approaches to optimize phosphorus use efficiency, improve yield stability, and promote sustainable wheat production.