A popular agronomic practice in GM crop production systems in Argentina and the USA is reduced tillage (Trigo 2011; Lee et al. 2012). In Argentina, reduced tillage has made it possible to reverse the negative consequences related to extensive use of arable land and has allowed a more efficient energy use balance for crop production (Trigo 2011). In this context, the use of GM maize hybrids tolerant to the herbicide glyphosate has simplified weed control and/or reduced the costs involved (Norsworthy and Frederick 2005). Furthermore, implementation of reduced tillage practices may provide additional benefits including improved soil fertility, reduced erosion, increased carbon sequestration, and the use of herbicides with better environmental profiles (Trigo 2011). Similar results were observed in the present studies, where the three GM maize hybrids enabled over-the-top applications of Faena Fuerte® with Transorb® and provided better and more cost-effective weed control than the conventional control hybrids.