Submitted to: Biocontrol News and Information
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/25/2007
Publication Date: 6/20/2007
Citation: Wyckhuys, K.A., Hopper, K.R., Wu, K., Straub, C., Gratton, C., Heimpel, G.E. 2007. Predicting potential ecological impact of soybean aphid biological control introductions. Biocontrol News and Information. 28(2):30-34 Interpretive Summary: Soybean aphid is a major pest of soybean which invaded the United States in 2000, putting whole regions of soybean production at risk. In China, soybean aphid rarely reaches damaging levels and has a diverse complex of predators and parasites. In the US, predators are commonly found preying on soybean aphid, but parasites are rarely collected on this aphid. US researchers have traveled to Asia to study the ecology of soybean aphid and identify candidate parasites for release in North America to control this pest. Exploration in China, Japan, and Korea yielded 21 populations of parasites of soybean aphid in at least 7 species that might be useful for its control. Host specificity testing narrowed the candidate to 4 species. More detailed studies on one of these, BINODOXYS COMMUNIS, have led to its authorization for release, and releases are planned for summer 2007.
Technical Abstract: The soybean aphid, APHIS GLYCINES, was first reported in the US in 2000; since then, it has spread to 22 states, putting >24 million hectares of soybean at risk. In China, APHIS GLYCINES rarely reaches damaging levels and has a diverse complex of predators and parasitoids. In the US, parasitoids are rarely collected from APHIS GLYCINES, so US researchers have traveled to Asia to study the ecology of APHIS GLYCINES and identify candidate parasitoids for release in North America. Twenty-six populations of aphelinid and aphidiine parasitoids have been collected in Asia and studied in quarantine facilities at USDA-ARS in Newark, Delaware, and the University of Minnesota in Saint Paul, Minnesota. These parasitoids were first tested against seven aphid species in five genera and two tribes on four host plant species in four families. Based on these evaluations, all but five populations tested were considered to have host ranges too broad for safe introduction. However, two species of BINODOXYS, two populations in the APHELINUS-VARIPES complex, and two populations in the APHELINUS-MALI complex had relatively narrow host ranges and may prove suitable for introduction. Further behavioural assays and analysis of ecological limitations showed that various factors would limit B. COMMUNIS parasitism of non-target aphid species. A permit for release has been granted for this parasitoid and field releases are planned for summer 2007.