Emerging Role of Polyamines in Plant Stress Tolerance

Plants, being sessile organisms, are challenged by variety of stresses in the form of abiotic and biotic components of environment. In such adverse conditions, plants evolve various adaptive strategies in order to survive. Among these strategies, accumulation of polyamines in plants helps to combat stress. Polyamines are ubiquitous low molecular weight compounds, which are now known to be involved in stress tolerance as suggested by various pieces of evidence during abiotic and biotic stress. The anti-stress properties of polyamines in plants are illustrated by their roles in modulation of morphological growth parameters, elevation of photosynthetic pigments, as well as declined content of stress indices, antioxidative enzymes, and non-enzymatic antioxidants content. The emerging role of polyamines in plant stress tolerance has been discussed in the present review. Keywords: Polyamines, plant growth regulators, physiological role, biotic stress, abiotic stress, environment.