The soybean aphid, Aphis glycines Matsumura (Homoptera: Aphididae), is a pest of soybean in Asia that was detected in the Midwestern United States in 2000. During the late spring and early summer of 2001, we evaluated the potential of indigenous predators to aid in the biological control of the soybean aphid. Potential predators were collected from soybean fields and no-choice feeding assays were used to determine which were capable of consuming adult and early instar aphids. These feeding assays were run in the laboratory after predators were starved for 24hrs. Ten adult aphids were placed in a Petri dish with an individual predator and then the remaining adult and early instar aphids were counted after a 24 hr. period. In the field, a clip cage experiment determined if early-season predation reduced or eliminated incipient colonies of the aphid. The clip cage experiment was located at the Michigan State University Entomology Farm, Ingham County, Michigan in plots that either contained or did not contain a predator refuge strip to determine if this conservation practice had a significant effect on predator abundance and impact. Both ground-dwelling predators (Carabidae and Staphylinidae) and foliar predators (Coccinellidae) were observed feeding on soybean aphids in no-choice feeding assays, though coccinellids consumed more on average than others tested. In the field, Harmonia axyridis (Coleoptera: Coccinellidae) larvae and adults and Coccinella septempuncata (Coleoptera: Coccinellidae) adults were common, and feeding assay results revealed that both of these species were highly predaceous on soybean aphids.
Species 1: Homoptera Aphididae Aphis glycines (soybean aphid)
Species 2: Coleoptera Coccinellidae Harmonia axyridis (multicolored Asian lady beetle)
Species 3: Coleoptera Coccinellidae Coccinella septempunctata (sevenspotted lady beetle)
Keywords: conservation, biological control
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA