Abstract

Restoration of Petrol Contaminated Soil by PGPR Consortium Producing Rhamnolipids and Enhancement of Growth and Antioxidant activity of Withania somnifera

Rajesh Kumar, Amar Jyoti Das and Asha A Juwarkar

Oil spills may considerably damage the soil quality. Increased contamination of agricultural soil by different hydrocarbons due to increased extraction and refinement of hydrocarbon are a serious environmental hazard due to their persistence in nature for a long time. Scope of bioremediation strategies is limited due to poor hydrocarbon accessibility and their low solubility which can be overcome by use of rhamnolipids, a class of biosurfactants. In the present study, pseudomonas strains (RK 4 and RK 3) isolated from contaminated soil identified by 16S rRNA were ascertained for PGPR as well as biosurfactants (rhamnolipids) property and checked for the compatibility to form consortium. Inoculating the strains and consortium of both the strain in petrol hydrocarbon contaminated soil and its interaction with Withania somnifera in presence of petrol oil reveals that rhamnolipids property of the strains helped in lowering the impediment effect of petrol engine oil hydrocarbons and the growth promotory activities enhanced the growth and antioxidant activity of Withania somnifera. Consortium of the both the strains showed positive results as compared to the individual strain and the interaction were found to be beneficial. The selected consortium of the strain could be further used for restoration of hydrocarbon contaminated soils for growing Withania sominfera.