Glyphosate e nitrgênio no controle de Brachiaria decumbens Stapf em capineiras estabelecidas

the objective of this experiment was to evaluate the efficiency of the use of the herbicide glyphosate associated with nitrogen fertilization in the control of brachiaria decumbens stapf in elephant grass stocking piles. the experimental design used was a randomized blocks with 17 treatments and three replications. the treatments were arranged in 4x4+1 factorial scheme, namely four doses of glyphosate (0, 720, 1440 e 2160 g/ha/application), four doses of nitrogen (0, 75, 150 e 225 kg/ha/ano) and one additional treatment (control with a hoeing). the application of the nitrogen and glyphosate, in the respective doses were performed immediately after the cutting of elephant grass. the association between glyphosate (2160 g/ha/application) and nitrogen (225 kg/ha/ano) was efficient in the control brachiaria grass in established elephant grass stocking piles. the application of the glyphosate (2160 g/ha/application) reduced the size of the bank of brachiaria grass seeds in the soil in 64%.