title: Bacterial rhizosphere and endosphere populations associated with grasses and trees to be used for phytoremediation of crude oil contaminated soil.
abstract: Different grasses and trees were tested for their growth in a crude oil contaminated soil. Three grasses, Lolium perenne, Leptochloa fusca, Brachiaria mutica, and two trees, Lecucaena leucocephala and Acacia ampliceps, were selected to investigate the diversity of hydrocarbon-degrading rhizospheric and endophytic bacteria. We found a higher number of hydrocarbon degrading bacteria associated with grasses than trees and that the endophytic bacteria were taxonomically different from rhizosphere associated bacteria showing their spatial distribution with reference to plant compartment as well as genotype. The rhizospheric soil yielded 22 (59.45 %), root interior yielded 9 (24.32 %) and shoot interior yielded 6 (16.21 %) hydrocarbon-degrading bacteria. These bacteria possessed genes encoding alkane hydroxylase and showed multiple plant growth-promoting activities. Bacillus (48.64 %) and Acinetobacter (18.91 %) were dominant genera found in this study. At 2 % crude oil concentration, all bacterial isolates exhibited 25 %-78 % oil degradation and Acinetobacter sp. strain BRSI56 degraded maximum. Our study suggests that for practical application, support of potential bacteria combined with the grasses is more effective approach than trees to remediate oil contaminated soils.
authors: Soil and Environmental Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), P. O. Box 577, Jhang Road, Faisalabad, Pakistan.
authors: Kaneez
authors: K
authors: Fatima
authors: Muhammad
authors: M
authors: Afzal
authors: Asma
authors: A
authors: Imran
authors: Qaiser M
authors: QM
authors: Khan
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D004787:Environmental Pollution; D006838:Hydrocarbons / Q000378:metabolism; D008129:Lolium / Q000378:metabolism; D010578:Petroleum / Q000032:analysis / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism; D006109:Poaceae / Q000378:metabolism / Q000382:microbiology*; D058441:Rhizosphere; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism; D014197:Trees / Q000378:metabolism
chemical_list: D006838:Hydrocarbons; D010578:Petroleum; D012989:Soil Pollutants