Enhanced remediation of diesel contaminated soil by the combined use of Lolium perenne and bacterial consortium

Rhizoremediation is a cost effective and aesthetically pleasing technology for the remediation of diesel polluted environment. The influence of diesel fuel contamination on Lolium perenne with bacterial consortium (Microbacterium schleiferi and Bacillus subtilis) on plant growth and hydrocarbon degradation was investigated. In this study, three different bacterial strains were grown at varying diesel oil concentration i.e. 0.5%, 1%, 1.5%, 2% and 2.5%. Bacteria were also screened for biosurfactant, indole 3-acetic acid production, phosphate solubilization, and antifungal bioassay. Microbacterium schleiferi and Bacillus subtilis were able to grow at 2% diesel oil concentration and exhibited plant growth promoting activities. Green house analysis revealed that augmentation with biosurfactant producing and plant growth promoting bacteria enhanced the plant growth and diesel oil degradation (80%) as compared to the treatments in which bacteria and plants were separately used. Therefore, the study concludes that application of selected strains with the Lolium perenne is a better approach for successful remediation of diesel oil contaminated soil.