The evaluation of some growth and physiological indicators and enzymatic activities in Conocarpus erectus L. under oil sewage and calcium oxide treatments

The identification of plants that are able to grow in the presence of oil pollutants or be effective in reducing pollution is very important. The experiment was acnducted in order to evaluate the phytoremediation rate and resistance of Conocarpus erectus L. under different oil sewage concentrations and calcium oxide levels in the Research Department of Horticulture, University of Hormozgan in 2009. Accordingly, four eaves seedlings were treated by oil sewage under five levels (0, 5, 10, 15 and 20 ml/kg soil), and calcium oxide under five concentrations (0, 2.5, 5, 7.5 and 10 percent). Despite the relative tolerance of seedlings to the oil sewage besed on the plant appearance, the results showed that the increasing of oil effluent concentration to 20 ml significantly decreased the vegetative traits such as shoot dry weight and root dry weight to 67% and 66%, respectively. In addition, 20 ml of waste oil reduced 50.6% peroxidase ascorbate enzyme activity and 62.1%of total solution protein. In comparison to control, waste oil at 20 ml level increased the ion leakage and lipids peroxidation to 51.8% and 42.8%, respectively. On the other hand, calcium oxide reduced damages of waste oil and improved vegetative traits such as shoot dry weight and root dry weight. Calcium oxide treatments also improved ion leakage, lipid peroxidation, and ascorbate peroxidase enzyme, and total solution protein. The use of Conocarpus erectus L for further phytoremediation studies can be useful. According to its relative resistance against oil sewage as well as the desired effects of calcium oxide on the plant, Conocarpus erectus L. could be introduced for phytoremediation in the oil -polluted soils.