Investigation of the effect of salt stress on the antioxidant enzyme activities on leaves of Date Palm (Phoenix dactylifera) seedling

The production of significant amount of reactive oxygen species (ROS) in salt stress condition causes damage to proteins, lipids, nucleic acids and other sites of cells, this process is a lethal factor for salt sensitive plants. Tolerant plants involved an antioxidant defense system which protects them against oxidative damage. Date palm is a salt-tolerant plant, to understand the regulation role of the antioxidant system provides protection against NaCl-induced oxidative damage in plants, the leaves used for the analysis of enzyme activities under long-term salt stress (NaCl with 0, 40, 80, 120, 160 and 200 mM) interaction on some antioxidant enzyme activities (superoxide dismutase (SOD), peroxidase (POD), catalase (CAT)) ascorbate peroxidase (APX), free proline and soluble protein contents in Date palm Hillawi cultivar (Phoenix dactylifera) was investigated. The activity of antioxidant enzymes catalase, peroxidase, ascorbate peroxidase, superoxide dismutase and prolin in the salt-tolerant cultivar increased markedly during salinity stress, while the soluble protein was mostly decreased by salinity stress. These results suggest that the antioxidant enzymes was a scavenging system forms the primary defense line in protecting oxidative damage under salt stress in date palm plants.