In this study, we report on the compatibility of two commercially available predatory mites, Neoseiulus californicus and Phytoseiulus persimilis, with three miticides used in greenhouse production systems to control the twospotted spider mite, Tetranychus urticae. We determined the lethal effects of the miticides chlorfenapyr, spiromesifen, and bifenazate to both predatory mite species 24 hours after exposure to spray applications in petri dishes. Two rates of chlorfenapyr (0.40 and 0.81 mL/2-L) and spiromesifen (0.15 and 0.31 mL·L–1), and one rate of bifenazate (0.62 mL·L–1) were used. All rates were based on the manufacturer label recommendations for twospotted spider mite. Both rates of chlorfenapyr and spiromesifen, and the single rate of bifenazate were not harmful to N. californicus with percent live mite values ≥85% for chlorfenapyr and ≥95% for spiromesifen, and 93% for bifenazate. However, these same miticides were substantially toxic to P. persimilis with percent live mite values of ≤63% for all the miticides tested. Based on the results of this study, the miticides chlorfenapyr, spiromesifen, and bifenazate are compatible with N. californicus whereas these miticides are toxic to P. persimilis indicating a difference in susceptibility based on predatory mite species.
Biological Control of the Twospotted Spider Mite (Trombidiformes: Tetranychidae) with the Predatory Mite Neoseiulus californicus (Mesotigmata: Phytoseiidae) in Blackberries
