Robab Ezazi, Masoud Ahmadzadeh,
Volume 3, Issue 2 (9-2014)
Abstract
Abiotic stresses are major environmental factors that affect agricultural productivity worldwide. Depending on the crop, the yield losses associated with abiotic stresses can reach 50 to 82 percent. Extreme temperatures, drought, salinity, flooding, freezing, ultraviolet light, heavy metals, nutrient deficiency, unsuitable pH, air pollutants and mechanical damage are the most basic stressors. Because biotic stresses cause metabolic toxicity, membrane degradation, reduction of photosynthesis, decrease of nutrient uptake, changes in levels of phytohormones and ultimately affect the plant growth and its productivity, therefore reducing the effect of these stresses, is essential. Plant growth promoting rhizobacteria play an important role in plant disease management and have a high potential in alleviation the abiotic stresses.