1.-The adverse changes in their environment are quickly recognized by plants, distinguished and responded to with reactions. Drought, heat, cold, salinity, radiation, hydric stress etc. are among the major abiotic stresses that adversely affect plant growth, productivity and profits.
2.-Abiotic stress reducing yields of major food and commercial crops by more than 40 percent and thereby causing economic loss. Water availability, water use efficiency, salinity and high temperature, are among the important abiotic factors.
3. Drought and salinity are be coming particularly widespread in many regions, and may cause serious salinization of more than 60 % of all arable lands in the world by the year 2040.
4.-Abiotic stress causes a morphological, physiological, biochemical and molecular changes that affect plant growth, development and productivity. Drought, salinity, temperatures (cold and heat) and oxidative stress are often interrelated; these conditions singularly or in combination induce cellular damage, that began with the production of free radicals.
5.-These stress stimuli are complex in nature, all of these abiotic stresses lead to oxidative stress and involve the formation of reactive oxygen species (ROS) in plant cells. Usually, plants have mechanisms to reduce the oxidative damage by the activation of antioxidant ways of defense. if the production of activated oxygen exceeds the plant’s capacity to detoxify. Typical symptoms being loss of osmotic responsiveness, wilting and necrosis.
6.-The balance between the production and the scavenging of activated oxygen that is critical to the maintenance of active growth and metabolism of the plant and overall environmental stress tolerance.
7.-Lipid peroxidation (LPO), triggered by lipoxygenases (LOX) and reactive oxygen species (ROS), is a hallmark of abiotic stress responses, both in signal transduction processes and during the execution of programmed cell death. Typically, LOX oxidize free fatty acids in the cytosol or chloroplasts, thereby initiating several oxylipin pathways including the jasmonate and hydroperoxide lyase pathway (Mosblech et al., 2009).
8.-Among the ROS typically produced in plant stress responses, only singlet oxygen and free radicals are sufficiently reactive to oxidize polyunsaturated fatty acids directly (Mueller et al., 2006). These short-lived ROS produced in different cellular compartments, including plasma membrane, plastids, mitochondria, peroxisomes, endoplasmic reticulum, and cytosol, are thought to oxidize predominantly glycerolipids close to the site of ROS production.
9.- In a recent study, single oxygen, was shown to be a major ROS species involved in photo-oxidative lipid oxidation and damage. However, the major sites and molecular targets of lipid oxidation as well as the relative contributions of different ROS species and LOXs to LPO and fragmentation have not been clarified.
10.-Compounds of OASIS/SUNOFF are a marker for free radical-induced lipid fragmentation associated with oxidative membrane damage and cell death.
11.- Compounds of OASIS/SUNOFF, have a role as a mobile signal under oxidative stress in plants. And the plants always are under different stress conditions.