European Red Mite Control on Apples in California

Abstract

Field trials for control of the European red mite, Panonychus ulmi (Koch), were conducted on Red Delicious apples near Watsonville, California, during the spring and summer of 1964. Naugatuck D-014 (2-( p-tert -butylphenoxy) cyclohexyl 2-propynyl sulfite); Morestan® (6-methyl-2,3-quinoxalinedithiol cyclic carbonate); Humble 70 viscosity oil; and Pennsalt 70 viscosity oil gave good seasonal control when applied once as preventive sprays at petal fall. Dinocap applied 3 times on a mildew-control schedule, also gave good seasonal control. Naugatuck C-940 (2-( p-tert -butylphenoxy)-l-ethylethyl o-tolyl sulfite) applied once at petal fall, and binapacryl, applied 3 times on a mildew-control schedule, gave satisfactory control for some time but permitted mite buildup before the end of the season. Union Carbide 19786 (2-sec-butyl-4,6-dinitrophenyl isopropyl carbonate) was not effective as a preventive spray. Ethion, Humble 60 viscosity oil, Humble 70 viscosity oil, and Volk Supreme oil gave good control when applied as midsummer therapeutic sprays. Chloropropylate® (isopropyl 4,4'-dichlorobenzilate) and Union Carbide 19786 were not effective as therapeutic treatments. Azinphosmethyl produced an initial reduction in mite levels but resulted in a severe mite resurgence. Preliminary observations on predator ratios suggest that azinphosmethyl and, to a lesser extent, Chloropropylate, UC 19786, and binapacryl may have a selective toxicity which affects predaceous phytoseiid mites more severely than P. ulmi