Interactive effect of potassium and spermidine protects growth, photosynthesis and chlorophyll biosynthesis in Vigna angularis from salinity induced damage by up-regulating the tolerance mechanisms

Pot experiments were conducted to evaluate the role of potassium (100 mg KCl / kg soil) and spermidine µM Spd) in regulation growth, chlorophyll synthesis photosynthesis Vigna angularis under salinity stress mM NaCl). Salinity declined by causing a significant decline δ-amino levulinic acid (ALA), prototoporphyrin IX (Proto IX) Mg-prototoporphyrin (Mg-Proto IX), however application K Spd alone as well combinedly alleviated considerable extent. Further, treated plants exhibited reactive oxygen species lipid peroxidation such effects also obvious stress. Photosynthetic rate, stomatal conductance, intercellular CO2 concentration, Fv/Fm photochemical quenching increased significantly due application, induced alleviation was maximal combined treatment. Up-regulation antioxidant enzymes activity, content ascorbic glutathione (GSH), accumulation compatible osmolytes strengthened tolerance against thereby lessening oxidative considerably. Accumulation phenols flavonoids Spd. caused increase Na concomitant with reflecting decreased Na/K. Results suggest that protect growth from damage up-regulating ion homeostasis, system, osmolyte secondary metabolite synthesis.