This study was carried out to assess the phytoremediation potential of Vernonia amygdalina (bitter leaf) and Talinum fruiticosum (water leaf) planted in crude oil contaminated soil. Soil samples were collected randomly from a site at the beginning of the rainy season. The experiment was conducted with different concentrations (0.1 and 1%) of crude oil-contaminated soil for 70 days. Soil samples were analysed for total organic carbon (TOC) using Walkey-Black chromic acid wet oxidation method and for total hydrocarbon content using UV spectrophotometer at the beginning and at the end of the experiment. The initial TOC levels in the control soil, 0.1% and 1% crude oil contaminated soil was found to be 0.28, 0.92 and 2.15% respectively. The initial THC levels in the control soil, 0.1% and 1% crude oil contaminated soil was determined to be 3.69 mg/Kg, 35.06 mg/Kg and 238.21mg/Kg respectively. The result showed 55 % growth in V. amygdalina plant height in uncontaminated soil, whereas; V. amygdalina transplants in 1% contaminated soil wilted by the 6th day of the experiment, V. amygdalina transplants in 0.1% contaminated soil died by the 30th day of the experiment, the transplants died. This indicates that the growth of V. amygdalina transplants was affected by the contaminants in the soil. T. fruiticosum transplants indicated a high potential of adaptation in the contaminated soil as shown by the growth after 10, 30 and 70 days of the experiment. These observations indicate that T. fruiticosum is less affected by contaminants than V. amygdalina.
Key Words: Phyoremediation, V. amygdalina, T. fruiticosum