Mechanisms of tolerance to salinity stress in plants as physiological and molecular aspect

Environmental stresses are the most important factors in reducing the yield of plants and agricultural products in Iran and all over the world. If environmental stresses did not occur, the actual yields should be equal to the potential yields of plants; while in many crops, the average true yield of plants is 20-30% of their potential yield. In certain parts of the globe, due to the specific geographic location, stressors have a more negative effect on agricultural production and agriculture in those areas has the tolerance to higher cost and lower yield. Iran is one of these countries that in most of its places major unsustainable stresses such as drought, salinity, wind, temperature and live tensions have led to decrease in yield and loss of soil fertility and, in some cases, inability to continue agriculture. For the development of salt tolerant varieties in saline areas, an integrated approach made by combining molecular tools with physiological and biochemical methods is essential. Therefore, studying different aspects of stress and a comprehensive review of the great research advances in biochemical, physiological and molecular mechanisms that regulate plant adaptability and tolerance to salt stress can be remarkably helpful in understanding the resistance mechanism and the development of resistant cultivars. Biotechnology, as a powerful and effective way, can be effective and useful in controlling various stresses. Biotechnology and Genetic Engineering researches, with the aim of increasing productivity on the one hand, and preventing losses and wastes on the other hand, allow to solve the problems of this sector by the least environmental wastes and spending minimum capital and provide fields of increasing the production of crops in a macro level with the goal of sustainable development. In this research, we have tried to discuss the environmental stresses and the effect of salinity stress on the plant and the mechanisms of coping with these stresses.