Growth Potentials of Cowpea (Vigna unguiculata L. Walp) on a Crude Oil Polluted Soil: A Screen House Experiment

The study was conducted to investigate the effect of the application of cow dung to crude oil polluted soils on the growth of cowpea. It was a screen house experiment. Four rates of cow dung (0, 1, 2 and 3 g) and four rates (0, 5, 10 and 15 ml) of crude oil per 10 kg of soil were used giving a total of sixteen (16) treatment combinations. Each treatment was replicated three times, for a total of forty eight (48) pots. The rate used is equivalent to 0, 200, 400 and 600 kg/ha and 0, 1000, 2000 and 3000 litres/ha of cow dung and crude oil respectively. The experiment was laid out in a completely randomized designed. Some plant growth parameters such as plant height, number of leaves and leaf areas were recorded at 7DAP, 2, 4, 6, 8 and 10 weeks after planting. The plant dry matter yield was also determined. Results obtained at the end of the field experiment showed that plant height increased from 5.8 cm to 114.6 cm at the rate of 5 ml crude oil and cow dung application of no amendment. There was a continuous increase in percentage germination, number of leaves, leaf area and dry matter yield. Generally remediation for the oil contaminated soil at the end of tenth week revealed a positive correlation coefficient in the degree of remediation during the trial periods.