Abstract: Antioxidant enzymes are related to the resistance to various abiotic stresses including salinity. Barley is relatively tolerant to saline stress among crop plants, but little information is available on barley antioxidant enzymes under saline stress. We investigated antioxidant responses of activities of Superoxide Dismutase (SOD), Catalase (CAT), Ascorbate Peroxidase (APX) Andguaiacol Peroxidase (GPX) to saline stress in two barley varieties named Hordeum vulgare L. var. Afzal and var. EMB82-12 treated with 50, 100, 200, 300, 400 mM NaCl for 3 days. The MDA contact of Afzal plants grown under different salt regimes remained nearly constant but it largely increased in EMB82-12 plants under the same conditions. There was a liner and significant correlation in CAT, APX, SOD, GPX activities in Afzal plants in response to increased salt concentration. The strong and positive correlation between antioxidant enzymes and salt concentrations, may account for the MDA level of Afzal plants remaining constant in response to different salt regimes. In general, the activities of antioxidant enzymes were increased in the root and shoot under saline stress. But the increase was more significant and consistent in the root. Among the antioxidant enzymes, CAT activity was increased the most drastically.
F. Khosravinejad , R. Heydari and T. Farboodnia , 2008. Antioxidant Responses of Two Barley Varieties to Saline Stress. Research Journal of Biological Sciences, 3: 486-490.