Changes in ROS-Scavenging Enzyme Activity in Rice (Oryza sativa L.) Exposed to High Salinity

We studied changes in the biochemical and physiological status and ROS-scavenging enzyme(superoxide dismutase, catalase and peroxidase) activity in leaves and roots of rice (Oryza sativa L.) plants exposedto high salinity. Under salt stress, the reduction in RWC (relative water content) in leaves was relativelysevere in comparison with that of roots. The proline content was also significantly higher in leaves of rice plantsfollowing salt treatment. The activities of CAT and POX in roots increased with increasing NaCl concentration,but the activity of SOD decreased. These results suggest that the increase of endogenous proline is closelyassociated with the increase of CAT and POX activities, which may play important roles in salt tolerance.Therefore, we conclude that the alleviation of oxidative damage and increased resistance to salinity may resultfrom the presence of efficient antioxidative systems.