| Rhizodegradaton is a method of soil treatment that utilizes the ability of bacteria in the root zone of plants to remove pollutants. One class of organic pollutants that shows potential for rhizodegradation is polycyclic aromatic hydrocarbons (PAHs). These toxic pollutants are found at numerous sites across the United States due to the residual waste of petroleum-based industries. In this study, the objective was to characterize plants and bacteria in the context of PAH rhizodegradation to find possible plant-bacteria combinations that may optimize pollutant removal. Members of the Cucurbit family, zucchini and pumpkin, showed tolerance to PAH exposure and the potential to promote soil decontamination. PAH-utilizing bacteria from the rhizosphere were found to grow on a range of aromatic compounds including plant root exudates. Populations of PAH-utilizing bacteria were not affected by plant species as much as the level of soil contamination. Bacterial strains were found to remove PAHs and carry catalyzing enzymes (Burkholderia sp. and Pseudomonas sp.) and colonize roots at high contamination levels (Stenotrophomonas sp.). These bacteria types show potential as bacterial inoculants for augmented PAH rhizodegradation. |
