Prey consumption by geocoris varius and G. proteus (Heteroptera: Geocoridae) provided with horticultural major pests in greenhouses

Abstract

We investigated the number of prey consumed in 24 h by 3rd and 5th instars of 2 species of polyphagous predators, Geocoris varius and G. proteus, provided with 4 prey species: Tetranychus urticae adult females, Frankliniella occidentalis 2nd instar, Aphis gossypii apterous adults, and Helicoverpa armigera eggs or 1st instar. The number of prey consumed differed significantly among prey densities in all predator×prey combinations, except in 3rd instar of G. varius provided with T. urticae or A. gossypii. Geocoris varius consumed prey maximally at higher prey density than G. proteus in 3rd instar with F. occidentalis larvae or H. armigera eggs, and in 5th instar, except with F. occidentalis larvae. Maximum numbers of prey consumed differed significantly between predator instars. Geocoris varius consumed more prey than G. proteus at 5th instar for all prey species. They also consumed more F. occidentalis larvae and H. armigera eggs than G. proteus at 3rd instar. These results show the higher predatory potential of G. varius and its promise as a biological control agent against major horticultural pests.