ABSTRACT
Plants are frequently subjected to environmental stresses such as water deficit, freezing, heat and salt stress. Soil salinity is a major problem in arid and semiarid regions, where rainfall is insufficient to leach salt and excess of sodium ion down and out of root zone. Salinity adversely affects plant growth and development, hindering seed germination, seedling growth, enzyme activity, DNA, RNA, protein synthesis and mitosis. Osmotic adjustment refers to lowering of the osmotic potential due to the net accumulation of solutes in response to salinity stress. Osmotic adjustment was important mechanism in salinity tolerance, because it enabled continuation of cell, stomatal and photosynthetic adjustments, better plant growth and yield production. Plant growth and development is expressed in terms of crop yield or plant biomass, which might be adversely affected by salinity, induced nutritional disorders. Phytohormones play an important role in alleviating salt stress and helps in creating the adaption mechanism.
