Control of Carmine Spider Mite on Cotton, 1983

Abstract

Abstract Varous newer chemical compounds were evaluatd for the control of the carmine spider mite on cotton at the Yuma Experiment Station in 1983. Plots consisted of 25 ft of row replicated four times. Treatments made on 23 Aug. were applied with a 2-liter CO2 pressurized sprayer unit using 20 gal/acre at 40 lb/in2 . Evaluations were made from 80 leaf samples per treatment (20 per plot) taken at random and examined in the laboratory with a SteroZoom microscope 3, 6, and 14 days following treatment. In all cases treatments appeared to be more efficient after 3 and 6 days with an increase at 14 days. this reflects limited residual action, partial ovicidal effectiveness, and the resurgence fo mites not killed. The most effective treatment was MK-936 at the higher rate (0.02 lb (AI)/acre). FMC54800 and UC81341 treatments provided satisfactory control. The standard. Comite, and FMC Spray Oil were not as effective as other treatments after 14 days but both of these were at a low rate. At this time of year Comite should be used at 2 pt/acre and the Spray Oil at 1% or higher. Coverage is another problem in controlling mites in that they inhabit the undersides of leaves. No phytotoxicity was observed.