Effect of different spray volumes in the control of citrus leprosis mite, Brevipalpus phoenicis (Geijskes), was studied. Two field trials were conducted in citrus (Citrus sinensis) orchards cv. Pêra-Rio located at Bebedouro, SP. The following treatments were used in a randomized block design: fenbutatin-oxide (Torque 500 FW) at 0.01, 0.02, 0.04 and 0.08% a.i., applied at 5, 10, 20 and 40 l per tree; water only, applied using the same volumes. Population assessments were conducted during the trial previous and after application. Ten fruits from each tree were sampled. Mites were removed from the fruits by means of an mite-brushing machine and counted under a stereoscopic microscope. It was concluded that the mitecide fenbutatin-oxide at the different concentrations and spray volumes presented high control efficiency with reductions in number of mites during the period of the experiments, that varied from 88.2% to 100% up to 63 days after spraying (experiment 1) and from 75.4% to 100% up to 123 days (experiment 2). This efficiency was dependent of spray volume rather than concentration, with higher volumes yielding higher reductions in populations. Spray volumes of 40 l/plant caused average reductions of 99.3% and 96.7%, independently of concentration.
Acari; fenbutatin-oxide; Citrus sinensis; chemmical control
