Oxidative biomarkers in leaf tissue of barley seedlings in response to aluminum stress

Cellular responses to Al-stress in Hordeum vulgare seedling bioassay were evaluated with an objective to identify the possible biomarkers in leaf tissue that would be best suited to biomonitor aluminum (Al) in the environment. Germinating seeds were treated with different concentrations of AlCl3 at pH 4.5 for 12 h. Al-uptake and accumulation in root and leaf, generation of reactive oxygen species (ROS: O2−, H2O2 and OH), cell death, activity of antioxidant enzymes: catalase, superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase, lipid peroxidation, protein oxidation, DNase activity and DNA damage were measured in leaf tissue of the seedlings on day 6 after treatment. The above parameters assessed in leaf tissue that followed a dose-response exhibited significant correlation with concentration of Al3+ in experimental solution as well as in root tissue. The findings underscored the sensitivity as well as potential of Hordeum vulgare seedling bioassay for biomonitoring of Al in the ambient environment.

► Al3+ taken up by barley seedlings was accumulated primarily in root.
► Accumulation of Al3+ in leaf tissue of barley seedlings was restricted.
► Leaf biomarkers showed strong correlation with Al3+-concentration in root tissue.