Revista Brasileira De Herbicidas 2015; 14(4): 271-279
Herbicides applied in pre-emergence to control Ipomoea spp. in sugarcane in dry season
The weed control through the application of long residual activity of herbicides is important strategy for the removal of these at different times of the year. The objective of this study was to evaluate the residual activity of herbicides applied pre-emergence of sugarcane on the morning glory of control in the dry season, and the selectivity of the herbicides sugarcane crop. The experiment was conducted in a randomized block design with four replications. The treatments were (g a.i. ha-1): hexazinone + diuron + sulfometuron (1,025.1 + 289 + 24.65); Amicarbazone (1,050); amicarbazone and sequential application of isoxaflutole (700 and 60); sulfentrazone (800); imazapic (133); tebuthiuron and sequential application of isoxaflutole (750 and 60), and a control without herbicide application. The hexazinone + diuron + hexazinone and amicarbazone caused Ipomoea hederifolia control levels of 96% and 92.5%, respectively. As for the Ipomoea quamoclit, all herbicides studied provided excellent levels of control. For Ipomoea nil, the herbicides hexazinone + diuron + sulfometuron, amicarbazone, amicarbazone and isoxaflutole and sulfentrazone control showed very good to excellent, while tebuthiuron and isoxaflutole herbicides only good level of control (88.8%) and imazapic with unsatisfactory level of control (45%). Therefore, it can be concluded that hexazinone + diuron + sulfometuron (1,025 + 289 + 24.65 g a.i. ha-1), amicarbazone (1050 g a.i. ha-1), sulfentrazone (800 g a.i. ha-1), and the sequential applications amicarbazone (700 g a.i. ha-1) and isoxaflutole (60 g a.i. ha-1), they can be considered as excellent alternatives for the control of different morning glory species (I. hederifolia, I. quamoclit and I. nil), while the imazapic (133 g a.i. ha-1) and the sequential application of tebuthiuron (750 g a.i. ha-1) and isoxaflutole (60g a.i. ha-1) can be considered as alternatives to control only Ipomoea quamoclit when applied in pre emergence of sugarcane crop in the dry season.
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