Abstract
Effects of plants on the foraging behavior of polyphagous natural enemies Piocoris varius (Uhler) and Geocoris proteus Distant were examined in the laboratory. We first examined the prey consumption rates of the two predator species, using Ephestia kuehniella Zeller eggs as the model prey on four different plant species: green pepper, strawberry, kidney bean and tomato. P. varius consumed significantly more prey eggs on green pepper and strawberry than they did on tomato, with the prey consumption rate on kidney bean intermediate among these plant species. Similarly, G. proteus consumed significantly more prey eggs on green pepper and strawberry than they did on tomato and kidney bean. These results suggest that both predators prefer green pepper and strawberry to tomato as suitable plants. Subsequent experiments using strawberry seedlings and prey eggs showed differences in feeding site preference between the two predators: G. proteus consumed prey eggs equally on both upper and lower compound leaves, whereas P. varius consumed prey eggs almost entirely on the upper compound leaves of the strawberry seedlings.
