Exogenous α-tocopherol improves growth and some physio-biochemical responses of salt-affected common bean

Spraying alpha-tocopherol (alpha-toc) is an efficient approach to nullify salinity injuries on plants. A pot trial was done in a semi-controlled greenhouse to investigate the efficiency of foliar spraying 1 mM alpha-Toc on the modulation of salinity stress (150 mM NaCl) in common bean (Phaseolus vulgaris L.). Salinity stress significantly diminished plant growth, leaf water potential (Psi pd), Stomatal conductance (gs), relative water content (RWC), residual transpiration rate (RTR), chlorophylla and chlorophyllb concentration. This reduction was linked to a notable rise in epicuticular wax load (EWL), carotenoid, proline, soluble sugar, polyphenol, sodium, potassium, calcium, and magnesium. As compared to nontreated salt-affected plants, spraying of 1 mM alpha-Toc considerably enhanced growth features, Psi pd, gs, RWC, chlorophylla, and chlorophyllb while also decreasing RTR, EWL, carotenoid, potassium, calcium, and magnesium. The data also show that spraying of alpha-Toc induces the accumulation of proline, soluble sugar, and polyphenol near untreated saltaffected plants, associated with a significant reduction in sodium content. Additionally, 1 mM alpha-Toc application decreased the number of significant correlations under salt stress. Current outcomes underscore the promise of alpha-Toc as a sustainable agronomic practice for cultivating common bean in saline soil. Further research must elucidate the precise molecular mechanisms underlying alpha-Toc's action in alleviating salt injury. Additional field studies are needed to validate these findings in varying climatic conditions.