[The production and scavenging of reactive oxygen species in plants]

The imposition of environmental stress leads to increased production of reactive oxygen species (ROS) in plant cells, Which can damage proteins, membrane lipids, DNA and other cellular components. Plants have evolved enzymatic and no-enzymatic protection mechanisms that efficiently scavenge ROS. Enzymatic detoxication system includes superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and glutathione peroxidase (GAX); no-enzymatic antioxidants include ascorbic acid, glutathione, mannitol and carotenoids, which occur in high concentrations in plants. The over-expression and accumulation strategies of these antioxidants in plants have been followed up to now, and have gained many transgenic plants showing increased stress tolerance.