Spray volumes, adjuvant and rainless intervals in weed control with sulfentrazone

Abstract

The herbicide sulfentrazone, used in sugarcane cultivation, is recommended for the control of eudicots and monocotyledons in pre-emergence and is also indicated for the control of Panicum maximum and Ipomea hederifolia. The research was carried out with the objective of verify the influence of the sulfrentazone herbicide with and without adjuvant on soil without straw cover under different periods without rainfall, associated to different application volumes, for the control of P. maximum and I. Hederifolia. The experimental design was a completely randomized, with four replications, in the 2x2x6+1 factorial arrangement, that is, two treatments of herbicide, two volumes of spray liquid (60 and 120 L ha^-1), six periods without rain before application another witness, who received no application. Weed counts were evaluated at 15 and 33 days after rainfall. The dry matter of the aerial part of the plants was also evaluated. The results indicated that the application of sulfentrazone with all treatments was effective in the control I. hedrifolia, independent of the volume of syrup, period without rainfall or presence of adjuvant. Even if P. maximum plants escape (emergence of plants) in all periods without rainfall, the treatments are effective for the control of the species. The presence of the mineral oil in the syrup with the herbicide sulfentrazone does not increase the control of P. maximum and I. hederifolia