Identification of Petroleum Resistant Plants and Rhizospheral Fungi for Phytoremediation of Petroleum Contaminated Soils

Petroleum pollution is a major and global disaster. Phytoremediation of petroleum polluted soils was based on degradation of oil using plants and its dependent fungi. A field study was conducted in a petroleum contaminated site at Arak refinery (Iran) to find the petroleum-resistant plant species and the rhizospheral fungi for being used in phytoremediation. Results showed that eight plant species were growing on the contaminated sites: Polygonum aviculare, Centureae virgata, Carthamus onyacantha, Alhaji cameleron, Glycyrrhiza glabra, Poa sp., Lactuca serula and Hordeum bulbosum. The germination assay showed that all studied plants are capable to survive in oil contaminated soils but they have different germination ability under petroleum pollution. 22 fungal species were found in the rhizosphere of the plants growing in the polluted areas; four of these species were common in all the plants and the others have species-specific distribution within the plants. The variation of fungi in petroleum-polluted areas was more than non-polluted zones. Culture of fungi in oil-contaminated media showed that although all the studied fungi were resistant to low petroleum pollution (1%) but a few species, especially Fusarium species, are resistant to higher petroleum pollution (10%).