Just the facts: A review of the biology and economics behind soybean aphid recommendations

University of Minnesota: Bruce Potter, Robert Koch & Phil Glogoza
Iowa State University: Erin Hodgson
Purdue University: Christian Krupke
Penn State University: John Tooker
Michigan State University: Chris DiFonzo
Ohio State University: Andrew Michel & Kelley Tilmon
North Dakota State University: Travis Prochaska & Janet Knodel
University of Nebraska: Robert Wright & Thomas E. Hunt
University of Wisconsin: Bryan Jensen
University of Illinois: Kelley Estes & Joseph Spencer

Before soybean aphid was identified as a pest of soybean in the U.S. in 2000, insecticide applications to northern soybean crops were rare, targeting sporadic insect and mite outbreaks. Although large infestations have been relatively uncommon since the early to mid-2000’s, the soybean aphid is unquestionably still the key insect pest of soybeans in many North Central states. A tremendous amount of research and observational data has been obtained for this pest since its introduction and we have the tools and the knowledge to manage this pest effectively.

The question is where to get the best information? There is a wide array of pest management advice and information available for soybean producers. The internet is particularly rife with newsletters, social media postings, and videos that all purport to give expert advice. It’s wise to always consider the source of the information and also evaluate what it is actually based on - making a statement with absolute certainty doesn’t necessarily make it a fact. As scientists at universities, we make pest management recommendations that are based on repeated and controlled studies, statistical tests and, ultimately, a system called “peer review” that ensures that what we publish is vetted thoroughly and evaluated by other scientists, often anonymously. However, for many of the sources of information available to soybean farmers, there is no review of any kind. As a result, many of the “recommendations” from entities not relying on sound science are never challenged or critically evaluated. As such, they are just opinions.

The Land-Grant University system and the Extension mission were created to conduct unbiased research and provide education for the public good. The soybean aphid management recommendations from Land-Grant Universities are based on replicated research that is evaluated by other agricultural researchers and educators (peer-reviewed) before it is published and disseminated. These recommendations aren’t just anecdotal, or based on hunches and feelings. They’re based on facts, established crop and pest biology, effectiveness of single or combined management tactics, short- and long-term economic costs and environmental implications.

As farmers and their advisors begin to find soybean aphids in their fields, the timing is right for a fact-based review of what is known about soybean aphid, their effect on yield, and cost-effective management of this pest.

This review was a cooperative effort by entomologists from several North Central states. The data behind our discussion represent the research efforts of many more. Topics pertinent to insecticide as a management tool for soybean aphids will presented as a series of brief blog posts over the next few days.