EFFECTS OF CRUDE OIL AS A SOIL CONTAMINANT ON SEEDLING GROWTH OF JATROPHA CURCAS L

ABSTRACT A study was conducted in 2010 to evaluate the effects of crude oil as a soil contaminant on the performance of Jatropha curcas seedlings in Asaba, Delta State, Nigeria. Oil concentrations used were 0.0, 2.0, 4.0, 6.0, 8.0 and 10.0% w/w. The experiment was arranged in a randomized complete block design with four replicates and monitored for 10 weeks after transplanting. The results showed that contamination of soil with crude oil significantly reduced (P 0.05) the performance of Jatropha curcas seedlings as regards plant height, number of leaves, leaf area and collar diameter when compared with seedlings grown in the uncontaminated soils. The performance of the seedlings was oil concentration dependent. Other symptoms observed at the higher levels of oil treatments were yellowness of leaves, leaf fall/drop, chlorosis, growth retardation and stagnation as well as wilting. This study has shown that crude oil in soil has a highly significant effect of reducing the performance of J. curcas seedlings. The oil level most tolerated by the plant is 2.0% w/w and above this level, significant reductions were recorded. This study has great implications on the sustainability of this multipurpose species, which has been identified as a potential biofuel species