Bioremediation of petroleum contamination in soils is based on the stimulation of petroleum hydrocarbon-degrading fungal and microbial communities. Earlier researches have shown that there are some petroleum-resistant plants and their root associated fungal strains were grown in oil-polluted soils. Senecio glaucus (Asteraceae) is one of the plants that was collected from the crude oilpolluted sites of Abadan refinery in Iran. The root-associated fungi of this species were determined and results showed the presence of six species associated with the roots of the plants growing in the polluted areas, but only three of them were found in non-polluted soils. The fungi were cultured in oil-contaminated media and results showed that all the studied fungi were resistant to low oil pollution (1 % w/w) and a few species, especially Fusarium species, showed higher resistance to oil pollution (10 % w/w) and it seems that they may be suitable for bioremediation in highly polluted areas. Bioremediation tests with Senecioa glaucus, with and without fungal strains, showed that application of both plant and its root-associated fungal strains was more effective than application of plant and fungi individually. Results indicated that fungal strains had the main role in bioremediation of crude oil-polluted soils but plant root exudates lead to an enhancement of the process.
