In vitro evaluation of the oxidative stress and genotoxic potentials of anthracene on mycorrhizal chicory roots

Most polycyclic aromatic hydrocarbons (PAHs) are ubiquitous natural and/or anthropogenic pollutants that have adverse effects on the human health and the environment. Little is known about their potential effects on higher plants and especially the mycorrhizal ones. In order to improve the understanding of the effects of PAHs on the partners of the endomycorrhizal symbiotic association, the oxidative stress and genotoxicity potentials of anthracene was investigated in Glomus intraradices-colonized and non-colonized transformed Cichorium intybus roots grown in in vitro cultures. Toxic effects of anthracene on the arbuscular mycorrhizal (AM) fungi was showed in the presence of increasing concentrations of anthracene (6.25–50 mg L −1), as compared to the control culture. The extraradical hyphae density and the sporulation intensity were drastically restricted in the presence of anthracene. The colonization of chicory roots was significantly affected. Chicory root lengths were reduced by 13% when grown on anthracene containing medium. The level of lipid peroxidation, as assessed by malondialdehyde (MDA) production, was markedly increased in colonized roots under anthracene treatment. The genomic alteration, as studied by the 8-hydroxy-2′-desoxyguanosine (8-OHdG) oxidative adduct formation, increased by about 2 folds in exposed roots as compared to the control. Significant decreases were detected in the MDA and 8-OHdG concentrations in colonized roots as compared to non-colonized roots exposed to anthracene. Taken together, these results suggested that endomycorrhization is able to give protection to the chicory roots against the lipid peroxidation and the genotoxicity of anthracene by preventing formation of MDA and 8-OHdG.