Kekere Otitoloju , Ajayi Oluwaferanmi Motunrayo

Department of Pant Science and Biotechnology, Adekunle Ajasin University, P.M.B. 01, Akungba-Akoko, Ondo State, Nigeria
Author    Correspondence author
Biological Evidence, 2024, Vol. 14, No. 4   doi: 10.5376/be.2024.14.0017
Received: 29 Jun., 2024    Accepted: 22 Jul., 2024    Published: 03 Aug., 2024

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Ajayi O.M., and Kekere O., 2024, Phytoremediation of soil contaminated with lead (Pb) and zinc (Zn) using Chromolaena odorata (L.) under greenhouse condition, Bioscience Evidence, 14(4): 125-131 (doi: 10.5376/be.2024.14.0017)

Elevated soil heavy metal level due to anthropogenic activities has continued to raise concerns in recent times. Phytoremediation is gaining popularity among environmentalists worldwide for its cost-effectiveness and environmentally friendly approach to removal of heavy metals from soil using plants. This study investigated potential of weed, Chromolaena odorata (L.), in remediating soil contaminated with lead (Pb) and zinc (Zn). The experiment involved growing C. odorata as potted plants in soil with varying concentrations (20-100 mg/kg) of Pb and Zn alongside a control treatment (0 mg/kg). Seedling survival was unaffected by both metals. In comparison to the control, there was no significant effect of Pb on number of leaves at 20-60 mg/kg but significantly increased it at 80-100 mg/kg. Zn grown plants had significantly reduced number of leaves at all the concentrations applied. Pb did not significantly affect stem girth while Zn led to its significant reduction at 60-100 mg/kg. Pb did not cause significant effect on leaf area except at 80 mg/kg where there was a significant increase, while it was not significantly affected by Zn. Both metals decreased root length without statistical difference from the control while number of roots was not affected. Fresh and dry weight values of plant parts were higher under contamination than the control. This was significant at 80-100 mg/kg for leaf and stem, and at 80 mg/kg for root. The plant was generally more tolerant to Pb than Zn in terms of growth. There were significantly higher concentrations of both metals in the parts of plants grown in metal contaminated soil than the control. Heavy metals were accumulated in plants grown with heavy metals than the control. C. odorata is a potential candidate for phytoremediation of soil contaminated with Pb and Zn, and can survive up to 100 mg/kg.

Siam weed; Heavy metals; Soil; Pollution; Remediation