This research area takes advantage of the relatively novel invasion of the soybean aphid, Aphis glycines, into North American agroecosystems.  The effects of this novel herbivore are far-reaching.  Both through its feeding and its vectoring of pathogens to soybean aphid can directly cause yield loss.  Aphids are also prey to a variety of resident predators which can increase in abundance and impact agroecosystems.  This research aims to understand the consequences of this invasion on other pests (herbivores and viruses), predators and how these effects propagate at the landscape scale.

RESEARCH PROJECTS

• Aphid-beetle-virus-soybean interactions
• Soybean aphid biological control
• Effect of nutrient stress on aphid performance

Aphid-beetle-virus-soybean interactions

This USDA-NRI funded project examines the potential reciprocal interactions among emergent pest complexes via a shared host, soybean.  Jack Donladson is studying whether above-ground (soybean aphid, Aphis glycines) and below-ground herbivores (Bean leaf beetle, Certoma trifurcata) can affect each other’s performance and if pathogens (Alfalfa mosaic virus and Bean-pod mottle virus) affect insect performance and preference.  The objective is to ultimately develop a conceptual model of how multiple plant stresses affect suites of co-occurring consumers.  In addition, in a USDA-RAMP funded project Emily Mueller is also examining whether soybean aphid is involved in the recent increase in incidence of aphid-borne viruses in crops such as snap-beans, which have not historically had virus problems.

Soybean aphid biological control

This NCRSRP-funded multi-state project aims to develop a classical biological control program against the soybean aphid.  Out team – which includes Bob O’Neil (Purdue), Matt O’Neal (Iowa State), and David Voegtlin (Illinois Natural History Survey) – is developing a framework for determining the likelihood of non-target effects of biological control releases.

Effect of nutrient stress on aphid performance

Although natural enemies of soybean aphid have been highlighted in the control of this pest, Scott Myers and I have been interested in how “bottom-up” factors affect aphid populations.  Ongoing studies in my lab have shown that nutrient deficiency, in particular K stress, is one factor that enhances aphid population growth rates and may contribute to aphid outbreaks [publications].