This research aimed to evaluate the efficacy of the herbicide sulphosate applied alone and in mixture with different adjuvants, compared to the herbicide glyphosate, both sprayed at low volume, to control red-rice (Oryza saliva L.) inpre planting condit ions of the rice crop. The experiment was conducted in the field; using the irri gated rice vari ety IAC -101. The fallow land was flooded for two days and after the area was drained, the red-rice began to germinate. When the weed reached approximately 20-25cm height, the herbicides were applied. Rice crop planting was performed 16 days after application at 60-80 seeds/linear meter density, 3cm depth and of 21 .8 cm inter-row spacing. The following treatments were tested: sulphosate at 1.20; 1.44 and 1.68K g a.i./ha and glyphosate at 1.20; 1.44 and 1.68Kg a.i./ha, which were applied alone and in mixture with the following adjuvants: Poliglicol, Organosil icone and Amina Graxa, be sides an untreated check. The following observations were made to evaluate the treatments effects: visu al phyt otoxic ity; % cont rol of red-rice; red-rice height (cm); crop height (cm) and the herbicides sulphosate, commercial formulation of Zaap at 2.5; 3.0 and 3.5 l/ha; glyphosate, Rodeo and Roundup commercial formulations, respectively, at 1.85; 2.22 and 2.59 1/ha, applied alone (except Rodeo) and in mixture with the adjuvants Mojante, Silwet and Frigate, resulted in excellent level of control of red-rice, when applied at post-emergence and total area, at pre-planting condition of rice crop implanted in direct planting system.
Glyphosate; Zaap; Mojante; Silwet; Frigate; Oryza sativa