Multiple Control Effects by the Polyphagous Predator, Geocoris varius (Heteroptera: Geocoridae) in Presence of Multiple Pest Species

Abstract

Geocoris varius is a native, polyphagous insect predator that attacks many greenhouse pests such as thrips, spider mites and aphids. So far, their pest-control ability was investigated by releasing G. varius nymphs on crops infested with single species of the pests. In this study, we investigated the multiple control efficiency of G. varius on multiple pest species, by releasing their nymphs on watermelon or strawberry plants infested with both thrips and spider mites, or aphids in addition to the two pest groups. In the watermelon fields where thrips, spider mites and aphids occurred simultaneously, G. varius controlled both thrips and spider mites, but not aphids. In the strawberry field where thrips and spider mites occurred simultaneously, G. varius controlled thrips only. Thus, we recommend the use of phytoseiid predatory mites together with G. varius to control spider mites as well as thrips in strawberry fields.