Applications of Microorganisms in Bioremediation of a Crude Oil Contaminated Calcareous Soil

A greenhouse experiment was conducted in a completely randomized design with factorial arrangement to investigate the influence of biological treatments (Pseudomonas fluorescens, Micrococcus yunnanensis, Claroideoglomus etunicatum and Funneliformis mosseae) on Vetiver grass grown on a crude oil contaminated calcareous soil (0, 2 and 4% crude oil). Results showed that the shoot and root dry weight and root colonization decreased in crude oil treatments. While the microbial respiration and total hydrocarbon concentration in post-harvest soil increased significantly. Soil inoculation with Micrococcus yunnanensis and Funneliformis mosseae had a positive effect on shoot dry weight but not for Pseudomonas fluorescens treatment. Iron concentration and iron and zinc concentrationsenhanced significantly in Claroideoglomus etunicatum and Funneliformis mosseae treatments respectively. Root colonization also increased when mycorrhiza inoculation applied to soil samples. Micrococcus yunnanensis and Funneliformis mosseae increased microbial soil respiration and total hydrocarbon content reduced in post-harvest soil. Our result showed that among tested microorganisms, Micrococcus yunnanensis and Funneliformis mosseae had more positive effects on bioremediation and plant growth in crude oil contaminated calcareous soil.