Soil pollution has been an important subject in recent decays. Due to adverse effects of organic and inorganic pollutants on human health and environmental safety, it is necessary to clean them from the environment. There are several methods to remove soil pollutants. Those are divided to 3 main parts, chemical, physical and biological methods. Due to side effects and costs of physical and chemical methods, it seems that biological methods specially phytoremediation, to be more efficient. Phytoremediation is considered as an environmental friendly, cheap and large scale method which uses plants to degrade, stabilize and remove organic and inorganic pollutants from the environment. One of the approaches to enhance phytoremediation efficiency is using of plant- microorganisms’ symbiosis. Endophytic fungi which live systemically within the aerial portion of many grass species, can improve plant tolerance to biotic and abiotic stresses. Phytoremediation of cadmium (Cd), arsenic (As) and petroleum hydrocarbons using of two plant species, tall fescue ( Festuca arundinacea ) and meadow fescue ( Festuca pratensis ), with and without Neotyphodium fungi (E + , E - ), have been investigated in this research. Plants seedlings were grown in a hydroponic system contained 0, 5, 10 and 20 ppm Cd and 0, 1, 2, 3, 10, 20 and 40 ppm As, for 8 weeks. The plants were also grown in the soil spiked with Cd and As separately in different concentrations (0, 10, 20 and 40 mg kg -1 soil) in the presence and absent of nitrilotriacetic acid (NTA) in the greenhouse (college of agriculture, Isfahan university of technology) for 2 months. Dry biomass of root and shoot, some photosynthesis parameters and Cd and As contents of plant and soil samples (using flame/graphite furnace- atomic absorption spectrometry) were analyzed. The plants also grown in the oil contaminated soil (Tehran Refinery, Landfill #3) for 7 months in a greenhouse. Concentration of 19 polycyclic aromatic hydrocarbons (PAHs) and total petroleum hydrocarbons (TPHs) in soil samples were analyzed using GC-MS and GC-FID. Results showed that the plants could accumulate Cd in their root and shoot more than the critical level of Cd hyperaccumulators, but their potential to transfer Cd from root to shoot was less than unit. Meadow fescue showed higher potential than tall fescue to accumulate Cd. Endophyte infected plants showed higher biomass (8-26 %), more Cd accumulation (6-16 %) and less stress than E - plants. Adding NTA increased Cd accumulation in plant tissues up to 1.5 to 3 times and also enhanced Cd transfer from root to shoot. Because of more Cd tolerance of E + plants in the presence of v Keywords : Soil Pollution, Bioremediation, Hyperaccumulator, Festuca arundinacea , Festuca pratensis
