GLYCINEBETAINE, PROLINE AND INORGANIC-ION LEVELS IN BARLEY SEEDLINGS FOLLOWING TRANSIENT STRESS

The changes in glycinebetaine, proline and major inorganic ions contents of barley seedlings after the imposition and withdrawal of salt (NaCl) stress have been measured. Glycinebetaine was found to be relatively non-labile in contrast to proline. The tissues adjusted osmotically to salt stress by NaCl accumulation. After stress withdrawal a proportion of the shoot Na+ and Cl- was retained, the former in exchange of K+ so that the pre-stress osmotic pressure was re-established. Polyethylene glycol (PEG) stress also produce a transient accumulation of proline but a more permanent accumulation of glycinebetaine. © 1979.