Management of Cyperus rotundus L. in pre-sprouted seedlings (PSS) of sugarcane systemThe sugarcane crop underwent several changes in the weed management scenario.Recently the sugarcane planting system was diversified, being able to be realized with pre-sprouted seedlings (PSS) of sugarcane.Weed management is constantly changing, due to the change in weed flora; however, Cyperus rotundus L. stands out because it appears at all times, due to the difficulty of control.The aim of this study was determine: A) the PPI (Period Prior to Interference), CPIP (Critical Period of Interference Prevention) and TPIP (Total Period of Interference Prevention) in sugarcane in the PSS system; B) Evaluate the chemical control of weeds in PSS with herbicides used for the management of C. rotundus; C) To evaluate the initial growth of PSS of sugarcane after the application of herbicides used for the management of C. rotundus; D) Evaluate the control and viability of C. rotundus tubers under herbicide treatment.For all experiments the sugarcane cultivars used was IACSP95-5000.To determine the critical periods, a field experiment was carried out in a randomized block design with fourteen treatments and three replications.The treatments were composed of seven coexistence periods and seven weed control periods: 0 -30, 0 -60, 0 -90, 0 -120, 0 -150, 0 -210 and 0 -240 days after planting (DAP).Were evaluated height, diameter, number of tillers, weight of ten stalks and yield.Control experiment was carried out in the field too, in a randomized block design, with ten treatments and four replications.The treatments application corresponding to the herbicides sulfentrazone (800 g a.i.ha - 1 ), diclosulam (193.17g a.i.ha -1 ), imazapic (133 g a.i.ha -1 ) e imazapyr (500 g a.e.ha -1 ) in pre-planting (um dia antes do plantio) and, halosulfuron (112.5 g a.i.ha -1 ), ethoxysulfuron (135 g a.i.ha -1 ), MSMA (1,975 g a.i.ha -1 ) and 2,4-D (1,340 g a.e.ha -1 ) in post-planting (30 DAP), and two control treatments (with and without weeding).In the control experiment were evaluated height, diameter, number of tillers, control, symptoms of injury and yield.The experiment of initial growth of PSS was performed in greenhouse, in a completely randomized design, with nine treatments and four replications.The treatments corresponded to the herbicides applied in pre-planting: sulfentrazone (200; 400; 800; 1,600 and 3,200 g a.i.ha -1 ), diclosulam (48.3; 96.6; 193.17; 386.34 and 772.68 g a.i.ha -1 ), imazapic (33.25; 66.5; 133; 266 and 532 g a.i.ha -1 ) and imazapyr (125; 250; 500; 1,000 and 2,000 g a.e.ha -1 ) and post-planting: ethoxysulfuron (33.75; 67.5; 135; 270 and 540 g a.i.ha - 1 ), halosulfuron (28.125; 56.25; 112.5; 225 and 450 g a.i.ha -1 ), 2,4-D (335; 670; 1,340; 2,680 and 5,360 g a.e.ha -1 ) e MSMA (493.75;987.5; 1,975; 3,950 and 7,900 g a.i.ha -1 ), plus one control treatment.Were evaluated symptoms of injury, height, diameter, number of tillers, chlorophyll A, B and total, leaf area, shoots and roots dry mass.The C. rotundus tubers viability experiment was carried out in a greenhouse in a completely randomized design, with nine treatments and four replications.The treatments were composed by herbicides applied in preemergence: sulfentrazone (800 g a.i.ha -1 ), diclosulam (193.17g a.i.ha -1 ), imazapic (133 g a.i.ha -1 ) and imazapyr (500 g a.e.ha -1 ), and post-emergence: halosulfuron (112.5 g a.i.ha -1 ), ethoxysulfuron (135 g a.i.ha -1 ), MSMA (1,975 g a.i.ha -1 ) e 2,4-