Rhizosphere Acidification Determines Phosphorus Availability in Calcareous Soil and Influences Faba Bean (Vicia faba) Tolerance to P Deficiency

Calcareous soils are known for their alkaline pH-promoting insoluble forms of certain nutrients, including phosphorus (P). Rhizosphere acidification is one the main physiological mechanisms mobilization by plants. However, specific and genotypic differences in response to P deficiency often observed, giving some genotypes particular tolerance abilities. This genetic potential gives us a new opportunity colonize unused lands, improve yield problematic soils, install sustainable agrosystems. To this end, potted experiment was conducted on three faba bean (Seville, SEV; Aguadulce, AGUA; Tunisian, TUN) cultivated calcareous soil (CS), as compared fertile (FS). Measurements made plant growth, SPAD index, photosynthesis, distribution, rhizosphere acidification, related interrelationships. induced symptoms deficiency, reduced concentration decreased net growth. significantly stimulated CS. activity determines bean. The genotype TUN more adapted calcareous-induced than AGUA SEV increasing activity, decreasing pH 0.6 units rhizosphere, having higher biomass production, remobilization, accumulation. key functional traits (plant chlorophyll biosynthesis, photosynthesis) strictly dependent availability, which remains close relationship with capacity (AC). tolerant (TUN) expressed lower stress index (SI) but use efficiency (PUE), H-ATPase uptake translocation shoots (PT), allowing it maintain better metabolic functioning. AC, PT, PUE, SI among management that promote resilient crops.