Leaf photosynthesis, chlorophyll fluorescence and ion content of barley (Hordeum vulgare) in response to salinity

Eight barley genotypes contrasting in their salinity tolerance were assessed for their chlorophyll fluorescence, photosynthetic performance, lipid peroxidation level and ionic content. A pot experiment was conducted in Borj-Cedria (Tunisia), in a wire house with a glass roof to avoid rainfall. The assay consisted of three treatments (0, 100 and 200mM NaCl) with eight barley genotypes following a completely randomized design. Each pot was considered as one replicate and nine replicates were used for each genotype and treatment. The salt-tolerant genotypes Kerkna and Tichedrett recorded the highest tolerance for photosynthesis and potassium accumulation, whereas the susceptible genotypes were mostly affected at severe salinity. Contrasting behavior was noted for fluorescence attributes, while PSII yield was unchanged reflecting good protection against photodamage. Photosynthetic performance, enhanced water use efficiency, maintained leaf K+ and oxidative defense remain the key components for tolerance mechanisms. Salt-tolerant barley could be suitable for management of salt-affected soils.