This experiment was carried out in Santa Bárbara do Oeste - SP - Brazil. The objective was to evaluate the efficacy of the herbicide sulfentrazone in the control of purple-nutsedge (Cyperus rotundus L.), and its selectivity on sugar cane. The soil of the area has high and low contents of sand (6 5.4%) and organic matter (1.6%), respectivelly. The sugar cane cultivar RB 76-5418 was planted on January 13, 1994. The experiment was designed in randomized blocks with four replications. The application equipment was a back pack sprayer with Teejet 110.03 XR nozzles, working at the pressure of 30 psi. The application volume was 300 Ilha. The herbicide was applied on January 20th; the soil was wet. The treatments were as follows: weedy and weed free checks; sulfentrazone applied in pre-emergence at the rates of 500, 600, 700, 800, 900 and 1000g a. ilha. The major weed was Cyperus rotundus with an average populational density of 312 plants/m2, 30 days after application. Sulfentrazone was selective to sugarcane at any rate and showed high control of purple-nutsedge in dosages iqual or superior to 800g a ilha.
Weed; selectivity; control; Cyperus rotundus; saccharum sp