The objective ofthis study was to evaluate the efficiency of two doses ofthe herbicide 2,4-D sprayed on Myriophyllum aquaticum plants and submitted to simulated rainfall during different periods oftime after application. The experiment was arranged in a completely randomized design, with four replications, in a factorial 2 x 8 (two herbicide doses and eight rain intervals). Herbicide 2,4-D was applied in the formulation DMA 806 in two doses, 670 and 1,340 g a.e. ha-¹ . Simulation of 15 mm rain for 5 minutes was performed in eight time intervals after herbicide spraying (0.25h, 0.5h, 1h, 2h, 4h, 8h, 12h, and no rain). Visual evaluations of control were carried out at 7, 14, 21, and 28 days after treatment application. The two doses ofthe herbicide 2,4-D were efficient in controlling the plants of M. aquaticum, even with the occurrence of rainfall 15 minutes after application.
efficiency; aquatic plant; weed, rainfall
