Abstract: Background: Glyphosate is the most widely used herbicide in Brazilian agriculture, and management techniques that increase its efficacy are important tools for the production system. Objective: Evaluate the effect of adding the nitrogen adjuvant ammonium sulfate [(NH4)2 SO4] to glyphosate on the control of Urochloa brizantha BRS Piatã and establish the best [(NH4)2 SO4] dose to mix with the herbicide. Methods: Two greenhouse experiments were conducted. In the first, six glyphosate doses (0; 33.75; 67.5; 135; 270; 540 g […]