Corn plants are tolerant to herbicide mesotrione due to yet underexplored biochemical mechanisms of detoxification. Up to now, it is postulated that this herbicide could be conjugated with Glutathione, Glucose or Cytochrome P450 and the conjugated molecule could be translocated for intra- (vacuoles) and/or extra-cellular (apoplast) compartments. This translocation mechanism could be accomplished through specific secondary transporters, which are energized by H⁺ pumps of the tonoplast (V H⁺-ATPase and H⁺-PPase) and plasma membrane (P H⁺-ATPases). Alternatively, the conjugated could be translocated through ABC (ATP-binding cassette) transporters. The aim of this work is to study the kinetics of the H⁺ pumps activities during the mesotrione detoxification process in corn tissues (roots, mesocotyls and leaves). The herbicide (192 g/ha) was applied on the leaves of 15 days-old plants, and the tissues were excised 3 and 7 days after application (DAA) to perform the vacuolar and plasmalemma vesicles preparation. For 3 DAA treatment it was observed a significant increase of about two-times of the vanadate-sensitive ATP hydrolysis for only mesocotyls samples, whereas the activities of roots and leaves were barely affected. On the other hand, at 7 DAA this activity was inhibited by 80% in mesocotyls, while it increased by 70% in leaves. The V-ATPase activity was increased by more than two-times in both roots and leaves. The V-PPase activity was over-stimulated 3 DAA in root vesicles (125%), mesocotyls (728%) and leaves (850%), and for 7 DAA, this effect was still higher in mainly in leaves (1530%). These results suggest that the H⁺ pumps are stimulated during the treatment with mesotrione, and that V-PPase seems to be the main enzyme involved in the plant cell detoxification process.