Abstract
Salinity stress is one of the most serious environmental factors limiting plant growth and productivity in large areas around the world. Priming approach was adopted to study the effect of glycinebetaine (GB) on enhancing salt tolerance of sensitive wheat cultivar (Gomeza 7). The caryopsis were primed in different concentrations of GB (25, 50, 100 mM) for 24 h, and then treated with or without 150 mM NaCl added to 1/4-modified Hoagland solution (MHS). The NaCl treatment lasted 38 d under natural environmental conditions. Salt stress reduced all growth parameters measured: fresh mass, dry mass, relative growth rate, for the shoots and roots, and relative water content (RWC). Salt imposition increased the level of Na
+
and Cl
−
, and reduced Ca
+2
and K
+
levels in both shoots and roots. Exogenous application of GB alleviated the deleterious effects of salinity on growth and mineral contents, the effect was more pronounced with 25 mM GB. Priming of caryopsis in GB counteracted the increase in the plasma membrane (PM) permeability and increased the cell solute potential, which was decreased by salinity. GB priming also increased the GB and glutathione concentrations, and reduced proline (Pro) as well as lipid peroxidation. Salt tolerance enhancement by GB priming might be occurred through reduced lipid peroxidation, increased GB and glutathione resulting in PM protection, and eventually ion homeostasis. The study is a valuable confirmation for enhancing salt adaptation via GB priming, which is of general interest for agriculture practices.