Mitigation of salt stress and stimulation of growth by salicylic acid and calcium chloride seed priming in two barley species.

The main objective of the current study is to underline the effects of salicylic acid or calcium chloride seed priming on plant growth, water content, chlorophyll content and photosynthetic activity of two barley species Hordeum marinum and Hordeum vulgare exposed to salinity (0, 100 and 200 mM NaCl). Results revealed that salinity decreased shoot and root growth, transpiration rate, chlorophyll concentration, stomata conductivity and water content in plants obtained from unprimed seeds. This reduction was dependent on the saline concentration used. However, Hordeum marinum species showed tolerance by maintaining tissue hydration, growth, photosynthetic assimilation and chlorophyll biosynthesis in stressed plants compared to controls. Moreover, priming seeds with salicylic acid or calcium chloride significantly improved all the above parameters under different salt treatments, suggesting that the effectiveness of this approach mainly depends on the priming agent applied and may vary with species and stress intensity applied. [ABSTRACT FROM AUTHOR]