ABSTRACT

Years of evolution and numerous adaptations have developed plants to be a unique eukaryotic multicellular organism which is independent in nature. One of such miraculous features of plant is its inbuilt defense mechanism which had protected itself from any extreme condition. Unfortunately, we human and our action had over exploited every natural resource to such an extent that the ―Mother Earth‖ which gave us life, are undergoing drastic changes hampering its actual ambience. One of the most recent concerning issues that had made scientist distressed is the rapid change of climatic condition of nature, which therefore followed by increase in rate of abiotic stress. Due to this increase abiotic stresses, high rate of ROS production takes place in plant which create an imbalance in its homeostasis. Reactive Oxygen Species (ROS) are highly reactive and toxic which effects the biosynthesis of chlorophyll, photosynthetic capacity, and carbohydrate, protein, lipid, and antioxidant enzyme activities. ROS is the byproduct of cellular metabolism of plant cell which triggers the stress signal transduction activating the defense mechanism, that is synthesis of antioxidants which maintains the level of this reactive species. The activity of several types of enzymatic and non-enzymatic antioxidant has greatly contributed on the defense mechanism of plants helping it to withstand the adverse condition of the environment. In this article, we will be assessing the process of how the plants physiological and biochemical changes take play on exposure to these abiotic stresses and how antioxidant in cell combat these changes for plant to survive.