A comprehensive multi-omics approach for understanding common bean's (Phaseolus vulgaris L.) response to phosphorus stress.

Common bean (Phaseolus vulgaris) is one of the most important legume crops for human consumption because of its nearly perfect nutritional composition. However, the crop yield is invariably constrained by phosphorus (P) stress across all farming systems. The present study aimed to unravel the mechanistic basis of common bean response to P stress at the early vegetative phase using an integrated multi-omic approach. In vitro experiments were carried out with P sufficient (P+) and total P deficient (P-) treatments using common bean SFB-1 seed cultivar. The plants were grown in MGRL media for a duration of three weeks. Various morphological traits were significantly reduced under P- stress conditions. There was a significant decrease in the levels of biochemical parameters such as free amino acids, secondary metabolites, and osmolytes (proline, total soluble sugars, and glycine betaine) under P- growth conditions. Additionally, photosynthetic pigments (such as chlorophyll a, chlorophyll b, total chlorophyll, and total carotenoids), physiological parameters (such as relative water content and stress injury), as well as both enzymatic and non-enzymatic antioxidants (including catalase, peroxidase, superoxide dismutase, total phenolics, and flavonoids), were also significantly reduced. Proteomic analysis identified two key proteins, homocysteine methyltransferase and DDB1-CUL4 associated factor 1-like protein, which are involved in various stress adaptation pathways. Furthermore, techniques such as FTIR spectroscopy, SEM, SEM-EDX, and intrinsic fluorescence spectroscopy were used to validate the metabolic changes induced by phosphorus deficiency. Phosphorus deficiency led to profound metabolic changes affecting photosynthesis, defense-related protein expression, cell wall composition, secondary metabolite production, levels of phytohormone precursors, free amino acids, antioxidant activity, and osmolyte accumulation, all of which contributed to inhibited plant growth and development.