Drought is the most important limiting factor for rice production in Asia. So it seems essential to increase the drought tolerance of this plant. Vesicular-arbuscular mycorrhizal fungi (VAM), the most common symbiotic soil fungi, improves plant growth and cause its better tolerance to abiotic stresses by creating asymbiotic relationship with host plant. The purpose of this study was to evaluate and compare the effect of mycorrhizal fungi on morphological traits of Sadri rice as a factorial experiment conducted in a completely randomized design with three replications. The levels of experiment was water logging (anaerobic condition), 90 and 60 percent of field capacity (aerobics condition) in the presence and absence of the fungi. Results showed that drought stress reduces plant height, diameter, length and surface of roots, leaf area, shoot and root dry weight. In contrast symbiotic mycorrhizal fungi had a significant increase for all traits in all three levels of stress. However the use of fungi in 90 percent was more effective than the other levels. So it can be concluded that mycorrhizal fungi could improve and strengthen the rhizosphere soil and root system of the plant to absorb water and nutrients. This may modify the undesirable effects of drought stress in plant.

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