The aim of this study was to evaluate different doses of Ethyl Methane Sulfonate in dual-purpose wheat seeds, and their answers on morphological traits, when measured in different evaluation periods. The experiment was conducted at 2013 crop year, in the experimental field of the Federal University of Santa Maria Campus Frederico Westphalen – RS, Brazil. The experimental design was a randomized block in a factorial design, two dual-purpose wheat genotypes x five doses of Ethyl Methane Sulfonate x four periods of evaluation, with four replications. Analysis of variance revealed a significant interaction among dual-purpose wheat genotypes x doses of Ethyl Methane Sulfonate x evaluation periods for leaf area and root diameter. It was observed interaction among dual-purpose wheat genotypes x evaluation periods of traits number of fertile tillers, plant height, tillers diameter and chlorophyll content. There was no interaction for root length. The dual-purpose wheat genotypes have differential behavior among themselves and evaluation periods, when the seeds subjected to the application of Ethyl Methane Sulfonate mutagen agent. Increasing doses of Ethyl Methane Sulfonate agent reveals variability for leaf area, root diameter, number of fertile tillers, tillers diameter and chlorophyll content; however, it has a negative effect on the length of the main root.