Induced DNA Damage Measured by the Comet Assay in 10 Weed Species

Abstract

For most plant species growing in polluted areas no mutagenicity assays are available. We have studied the possibility of using the alkaline protocol of the Comet assay as a method for detecting induced DNA damage in wildly growing weeds. The monofuctional alkylating agent ethyl methanesulphonate (EMS) was applied on leaves of 10 weed species (ordered according to the diameter of the nuclei): Arabidopsis thaliana, Convolvulus arvensis, Bellis perennis, Urtica dioica, Lamium album, Chenopodium rubrum, Plantago media, Poa annua, Taraxacum officinale, and Agropyron repens. With increasing concentrations of EMS (2 to 10 mM) the DNA damage, expressed by the averaged median tail moment values, significantly increased in nuclei of all weeds studied. Using the Head Extent parameter of the Komet version 3.1, we have measured the diameter size of the nuclei of the 10 weed species either immediately after the isolation of the nuclei or after 20 or 45 min of treatment with alkaline buffer (pH > 13). According to the increase of the diameter of the nuclei (including the formed halo) resulting from the to alkaline buffer treatment, electrophoretic conditions (unwinding and electrophoresis time) for the Comet assay can be selected for the individual weed species.