Decreasing soil mobilization in no-till is essential in order to reduce the risk of soil erosion and the development of weeds. The objective was to evaluate soil mobilization and seeding depth by the action of mechanisms for residue management in the seeding row of a direct seeder. The experiment was conducted in a clay soil under no-tillage with 10.7 Mg ha-1 of sorghum residue mechanically managed. The experiment had seven treatments composed by the combination of two mechanisms ahead of the shank, (flat cutting disc and row cleaners) and three mechanisms behind the double discs (disks covering models “vence-tudo”, M1 and Spider). The results showed the row cleaners without any covering mechanism had the highest soil mobilization area (105 cm²) and the combination of flat cutting disc with M1 had the lowest value (35.3 cm²). Evaluating the data set, there are shoaling gains when added coverer mechanisms to the row cleaners and the cutting disc at least 10% and 26%, respectively, improving the depth of the corn seed to 0.013 and 0.011 meters, respectively. But the breaker blade mechanism and their association with the covering models “vence-tudo” and M1 prototype were the ones that had the further deepening of the seeds and the lower mobilization soil inside the furrow and greater soil returns by the coverers.
Zea mays; no-tillage; agricultural mechanization; furrowers
