Genotypic Differences in the Physiological Response of Faba Bean (Vicia faba L.) to Phosphorus Deficiency

Abstract

This study investigated the physiological responses of four distinct Faba bean (Vicia faba L.) genotypes, Seville (SEV), Aguadulce (AGUA), Tunisian (TUN), and F7, when subjected to phosphorus deficiency, with a particular focus on their responses in terms of growth, chlorophyll pigments, photosynthetic activity, and nutrient efficiency. The results revealed that growing Faba bean in a phosphorus-deficient environment induced a reduction in the plant growth, net photosynthesis, SPAD index, and tissue phosphorus content. Genotypic variations were observed, with TUN demonstrating relative tolerance as compared to the other genotypes, by exhibiting a higher capacity for phosphorus uptake under deficiency conditions, lesser phosphorus deficiency stress index (PDSI), higher phosphorus tolerance index (PDTI), and better phosphorus use efficiency (PUE). The latter are two physiological traits that discriminate the studied genotypes. They can be used for further screening programs. Our research contributes to a broader understanding of how Faba bean plants react to phosphorus deficiency, shedding light on the genetic variations.