Growth performance of cucumber ( Cucumis sativus L.) in spent engine oil contaminated soil amended with compost of Urena lobata L.

Abstract

Studies to investigate the growth performance of Cucumis sativus L. (variety Nandini 731 F1) in spent engine oil contaminated soil amended with compost of Urena lobata was investigated at the University of Port Harcourt Ecological Centre. The soil samples were polluted at four different concentrations, namely, 2%, 3%, 4% and5% with spent engine oil and amended with decomposed Urena lobata at the rate of 0.25 kg per 3 kg of soil alongside a control (0%). The growth parameters examined were: plant height, number of leaves, leaf area, stem girth and sprouting percentage. The study showed that the control treated with compost gave the highest values for plant height 23.73 cm, number of leaves 16.33, leaf area 84.73 cm2 and stem girth 2,2 cm while the 5% contamination recorded the lowest values for plant height 1.83 cm, number of leaves 1.33, leaf area 2.19 cm2 and stem girth 0.1 cm. The number of leaves significantly (P<0.05) decreased with increase in the concentrations of spent engine oil from 2% to 5%. The 0% + compost treatment recorded the highest number of leaves while the number of leaves for 0% alone was comparable to 2%, 3% treatments but higher than 5% treatments. The growth parameters decreased with increase in the levels of contamination, however the application of Urena lobata significantly increased the plant height, number of leaves, leaf area and stem girth at P<0.05. This study suggests that compost of Urena lobata is an effective organic supplement for remediation of spent engine oil contaminated soil where Cucumis sativus is cultivated.