Enzymatic response and metal ion content in roots of corn and broad beans planted in soil contaminated with gasoline

The first reaction of plants to the presence of the petroleum hydrocarbons in their medium (growth environment) and after the penetration of the contaminants into their tissues is the induction of internal defense mechanisms like enhancing antioxidant enzymes activity, which varies among plant species. The objective of this study was to evaluate the antioxidant enzymes activity and metal ions contents (iron, manganese, and zinc) in broad beans without bacteria and compare the findings with corn at different levels of soil contamination with gasoline (0, 1, 2, 3, and 4%). The main results demonstrated that the activities of superoxide dismutase, peroxidase, and malondialdehyde concentration and the metal ions contents were significantly different between corn and beans. The activities of superoxide dismutase and catalase, concentrations of malondialdehyde and magnesium, and fresh root weight and root length in corn were more significant than the beans. Conversely, peroxidase activity and concentrations of iron and zinc ions in the beans increased. Ultimately, in the absence of bacteria, the corn plant showed superior growth compared to the broad beans under gasoline contamination.