Deposição de calda e controle de plantas daninhas empregando pulverizador de barra convencional e com barra auxiliar, em volumes de calda reduzidos

Application technology directly influences the success of desiccation, supporting the effectiveness of weed control. This work evaluated herbicide deposition on the weeds, spray loss to the soil and the efficacy of weed control by two application technologies (conventional boom sprayer and auxiliary boom sprayer, by varying the spray volumes between them: 100 and 150 L ha-1 in the conventional system and 30 and 50 L ha-1 using the auxiliary boom). The experiment was conducted in a randomized block design with five replications. A tracer was added to the solution containing the herbicide glyphosate, to be detected by spectrophotometry. Spray deposition on the weeds did not differ depending on the presence or absence of the auxiliary boom, nor the spray volumes, showing the feasibility of using spray volumes between 30 and 50 L ha-1 with the auxiliary boom. Soil losses were higher when the conventional spray boom was used. The efficacy of weed control was very good, regardless of the treatment used.