CONTROLE DE Amaranthus deflexus, Ipomoea hederifolia E Cyperus rotundus COM DIFERENTES ASSOCIAÇÕES DE HERBICIDAS APLICADOS SOBRE PALHA DE CANA-DE-AÇÚCAR

Abstract

The objective of this work was to evaluate the control of Amaranthus deflexus, Ipomoea hederifolia and Cyperus rotundus through herbicides association applied on sugarcane straw from cultivar RB966928. The experiment was carried out in a commercial area in Tarumã - SP region, in randomized blocks, with 7 treatments and 3 replicates. The plots were composed of five sugarcane lines spaced 1.50 m with 5m length (37.5 m²), where the present infestation is natural of the area. The treatments were constituted by associations of more than one herbicide in an agitator tank, where: tebuthiuron+diclosulam (900 + 123 g i.a. ha-1); tebuthiuron+flumioxazin (900 + 150 g i.a. ha-1); isoxaflutole+imazapic (120 + 112 g i.a. ha-1); tebuthiuron + sulfentrazone (900 + 900 g i.a. ha-1); tebuthiuron + amicarbazone (900 + 910 g i.a. ha-1); isoxaflutole+hexazinone (120 + 224 g i.a. ha-1); diuron+hexazinone+ sulfometuron methyl (1387 + 391 + 33.35 g i.a. ha-1) and control with and without weeds. The application was carried out on a tratorized way with pressure and volume of constant syrup (ou silt??) of 150 L ha-1, in pre-emergency of the weeds. The control efficiency evaluations were performed at 30, 60, 90 and 120 days after the treatment (DAT). The herbicidal mixtures tebutiuron + sulfentrazone (900 + 900 g i.a. ha-1); tebutiuron + amicarbazone (900 + 910 g i.a. ha-1); isoxaflutole + hexazinone (120 + 224 g i.a. ha-1) obtained satisfactory controls of the three weeds simultaneously in all evaluation periods. The association of tebutiuron + sulfentrazone (900 + 900 g i.a. ha-1) was the only treatment that achieved 100% of control efficiency for the invasive triad at 120DAT.