Effect of Salinity Stress on Slow- and Fast-Growing Festuca Grass Species

Document Type : Original Article


 IMPROVING tolerance to salinity stress is a major challenge in many regions worldwide. In this study, the effect of salinity stress on slow- and fast-growing Festuca species was examined. Plants were exposed to 0, 50, 100 or 200 mM of NaCl for two weeks in a greenhouse using a hydroponic culture system. Shoot dry mass, water status, membrane stability were monitored as well as contents of proline, sodium, potassium, calcium, magnesium, nitrogen and phosphorus. Salinity stress had negative effects on shoot dry mass, water status, and membrane stability. Although fast-growing species had higher shoot dry mass, the slope of decreases were much higher in the fast-growing species. Slow-growing species showed greater accumulation of Na+, greater increases in ion leakage and Mg content and greater decreases in proline content. The results suggested that the interspecific differences among species in resistance to salinity stress associated mainly with tolerance ability to salinity stress rather than avoidance ability. The difference is due mainly to growth habits which is associated mainly with relative growth rate and leaf properties. Also, there was interference of Mg, but not Ca, on Na+ uptake by plant shoot, in addition to the important role of proline content in tolerance mechanism.