When plants are subjected to stress conditions, highly reactive
oxygen species ROS (cytotoxic species) are produced. In
the absence of any protective mechanism, excessive amounts
of ROS can seriously disrupt the normal metabolism through
oxidative damage to lipids, protein and nucleic acids. They can
enhance membrane lipid per-oxidation, electrolyte leakage,
damage chloroplast; inhibit photochemical reactions, decrease
photosynthesis and loss of cell membrane integrity. The
balance between ROS generation and scavenging may be
disrupted by salt stress and high light or UV exposure. Plants
have a number of antioxidant enzymes protecting themselves
that used as indicators for the salinity stress (Chen et al., 2011).
In the field, the solid phase of the soil system, the concentration
and composition of the solutes in the soil solution
and its pH control the concentrations and activity of the