Effects of some insecticides on Kampimodromus aberrans:laboratory and field studies

Abstract: Kampimodromus aberrans is an important predatory mite in European vineyards andfruit orchards. Pesticides can exert profound effects on K. aberrans populations that areinfluenced by the pesticide experience of predatory mites. Resistance to organophosphates anddithiocarbamates has been suggested for some Italian populations of K. aberrans but thisphenomenon has not been shown in the laboratory. The effects of three different pesticides(chlorpyriphos-ethyl, methoxyfenozide and flufenoxuron) on K. aberrans were investigated infield and laboratory conditions. In field tests, predatory mites were released at the beginning ofFebruary on defined plots. Kampimodromus aberrans densities were evaluated on insecticidetreated plots and on control plots by examining leaf samples in the laboratory from June toAugust. The lethal and sub-lethal effects of the same pesticides were tested in the laboratoryusing a residual bioassay. Field experiments showed some effects of the three pesticides onpredatory mite populations. Results of bioassays were partially correlated with those obtained inthe field. Implications for IPM are discussed.