Assistência de ar e volumes de aplica??o na deposi??o de calda e no controle do arroz vermelho (Oryza sativa L.)

摘要

The aim of this research was to evaluate the effect of air-assistance on spraying at three volumes in spray deposition and control of red rice under fodder radish cultivation. To evaluate the control of this weed and spray deposition were used paraquat herbicide and a Brilliant Blue dye, respectively. The three spraying volumes were 100, 200 and 300 L ha-1, using a tracer dye at 1,500 mg L-1. Both solutions and volumes were sprayed with flat fan nozzles AXI 110015 at 117.3 kPa, AXI 11002 and AXI 11003 at 276 kPa, respectively, with and without air-assistance on the boom. The evaluation of deposition was made on red rice leaves. The highest spray volumes (200 and 300 L ha-1) permitted to obtain greater dye deposits with air assistance in the spray boom. No difference it was observed on spray deposition at 100; 200 and 300 L ha-1 volumes without air assistance and at 200 as well as 300 L ha-1 with air assistance. The highest percentages of red rice control were obtained with 300 L ha-1 without air assistance as well as for all spray volumes using this technology.