QUALITY OF SOWING AND DEVELOPMENT OF MAIZE AS A FUNCTION OF BLACK OAT MANAGEMENT METHODS APPLIED IN DIFFERENT PERIODS BEFORE MAIZE SOWING

The correct straw management in no-tillage system is necessary and has demonstrated to be an excellent alternative to improve sowing quality. Cover crop management periods may compromise the performance of planters and the productivity of the successor crop. The objective of this study was to evaluate the effect of black oat management methods, carried out in different periods before maize planting, on the quality of sowing and development of the crop. Two experiments were conducted in the municipality of Coimbra, MG: the first in 2013 and the second in 2016. Randomized block design was used in both experiments, in split-plot arrangement (4x3), with four replications. The plots consisted of four black oat management periods (21, 14, 7 and 0 days before sowing) and the subplots consisted of three black oat management methods (desiccated, rolled and cleared). The plants were managed in the flowering stage. The characteristics evaluated were: average, faulty, double and normal spacing between plants; sowing depth; emergence speed index; plant stand; and uniformity of plant development in V5 stage. In both experiments, the desiccated black oat presented lower emergence speed index, plant stand and uniformity of plant development. The mechanical managements of black oat, regardless of the period before maize planting, improve the quality of maize sowing, with significant reduction of faulty and double spacing, and promote proper plant development.