Effect of Late-Season Fenvalerate and Flucythrinate Applications on European Red Mite (Acari: Tetranychidae) and Tufted Apple Bud Moth (Lepidoptera: Tortricidae) Populations on Apple

Abstract

Field studies were conducted from 1982 to 1984 to investigate the effects of selectively timed applications of the pyrethroids fen valerate and Oucythrinate on control of tufted apple bud moth, Platynota idaeusalis (Walker), and density of overwintering European red mite, Panonychus ulmi (Koch), eggs. The pyrethroids effectively controlled tufted apple bud moth, especially during Brood II, with only two alternate row-middle (ARM) applications in comparison with five ARM applications for standard organophosphate and carbamate insecticides. However, effect of the pyrethroid applications on the density of overwintering European red mite eggs depended on timing and rate. Applications of pyrethroids before 23 and 16 August in 1983 and 1984, respectively, increased the density of overwintering European red mite eggs in comparison with organophosphate and carbamate insecticides. A four-fold increase in the rate of fenvalerate was followed by an approximate three-fold increase in overwintering European red mite egg density. Results suggested that selectively timed applications of pyrethroids during Brood II oviposition and egg hatch may be used to prevent fruit injury by tufted apple bud moth without causing an increase in the density of overwintering European red mite eggs.