Rhizosphere assisted bioengineering approaches for the mitigation of petroleum hydrocarbons contamination in soil

The high demand for petroleum oil has led to hydrocarbon contamination in soil, including agricultural lands, and many other ecosystems across the globe. Physical and chemical treatments are effective strategies for the removal of high contamination levels and are useful for small areas, although with concerns of cost-effectiveness. Alternatively, several bacteria belonging to the Phylum: Proteobacteria, Bacteroidetes, Actinobacteria, Nocardioides, or Firmicutes are used for biodegradation of different hydrocarbons - aliphatic, polyaromatic hydrocarbons (PAH), and asphaltenes in the oil-contaminated soil. The rhizoremediation strategy with plant-microbe interactions has prospects to achieve the desired result in the field conditions. However, adequate biostimulation, and bioaugmentation with the suitable plant-microbe combination, and efficiency under a toxic environment needs to be evaluated. Modifying the microbiomes to achieve better biodegradation of contaminants is an upcoming strategy popularly known as microbiome engineering. In this review, rhizoremediation for the successful removal of the hydrocarbons have been critically discussed, with challenges for making it a feasible technology.HIGHLIGHTSPetroleum hydrocarbon contamination has increased around the globe.Rhizoremediation has the potential for the mitigation of pollutants from the contaminated sites.An accurate and detailed analysis of the physio-chemical and climatic conditions of the contaminated sites must be focused on.The suitable plant and bacteria, with other major considerations, may be employed for in-situ remediation.The appropriate data should be obtained using the omics approach to help toward the success of the rhizoremediation strategy.