George Heimpel and his research group at the University of Minnesota have been working on biological control of the soybean aphid since 2001. They have used a number of methods, including releases of specialized aphid parasitoids from Asia, and promoting native biological control through plant diversification strategies.
Heimpel applied for an NCR-SARE Research and Education grant in 2013, and was awarded $178,558 to identify favorable conditions for release and establishment of the Asian parasitoid wasp Aphelinus glycinis, a biological control agent approved for release by the USDA.
Heimpel released A. glycinis at two sites of the U of MN Agricultural Experiment Station in the summer of 2013, at two organic soybean farms during the summer of 2014, and into a buckthorn stand at the U of MN Agricultural Station in St. Paul in the Fall of 2014 (buckthorn is the overwintering host of soybean aphid).
The research is ongoing, but Heimpel has learned that A. glycinis can be released into soybean fields successfully using the methods his team developed during 2013. They have also developed a sleeve cage method for assessing overwintering success and implemented it for the first time over the 2014-2015 winter.
“We have shown that A. glycinis can cause significant mortality of soybean aphids in the months post-release,” said Heimpel. “However, this parasitoid will need to be able to overwinter to become established in Minnesota.
Heimpel hopes this project will lead to improved protocols for establishment of A. glycinis, as well as parasitoids released in other cropping systems. He says sustainable biological control of soybean aphid would lead to increased profitability, decreased exposure to insecticides, and therefore increased quality of life for growers, “This research would also be some of the very first field-based work with Aphelinus glycinis in North America, representing a novel and timely contribution to efforts to control soybean aphid, a damaging pest found in all 12 states in SARE’s North Central Region.”
View George's presentation on this project, from the 2015 Farmers Forum, through NCR-SARE's YouTube playlist. Visit www.youtube.com/NCRSAREvideo for this and other videos.