The efficacy of three wild-type legumes in the remediation of agricultural soils contaminated with 1% (lightly impacted), 3% (moderately impacted), and 5% (heavily impacted) crude-oil was assessed, using soil physicochemical and biochemical properties (soil quality indicators) as evaluation criteria. Results after a 15-month remediation period showed that only L. leucocephala failed to germinate. The level of MC (87%) as well as the activities of Lipases (103%) and ALPs (90%) in the P. pterocarpum-remediated soil samples were significantly (p>0.05) elevated, relative to their respective contaminated samples, while the TPH (60%), was significantly (p>0.05) reduced. The C. retusa-remediated soils had the level of MC (48%) and the activities of Lipases (59%) and ALPs (73%) significantly (p>0.05) elevated, relative to the respective contaminated samples, while the level of TPH (65%) was significantly (p>0.05) reduced. The levels of pH, and TOC as well as the activities of the dehydrogenases and ACPs were not significantly (p<0.05) different from their corresponding contaminated samples remediated by both legumes. These results indicate that Leucaena leucocephala ‘may’ not be a good crude-oil remediating leguminous plant, while both Peltophorum pterocarpum and Crotalaria retusa are good crude-oil remediating leguminous plants.
