Research Highlights

Finding Biopesticides and Seed Treatments for SCN and SDS Control

By Barb Baylor Anderson

Soybean cyst nematode (SCN) is a real challenge for farmers growing soybeans in Minnesota, as well as across the rest of the United States. That’s because there just aren’t very good chemical controls available and plant genetic resistance is rapidly breaking down. 

Likewise, sudden death syndrome (SDS), which often develops in fields infested with SCN, can be a challenge. As with SCN, SDS can be tamed via the right variety selection. Seed treatments also can be effective for reducing yield loss for SDS, but most fungicides are not effective.

“It will be critical in the near future to find new solutions for managing particularly SCN and we aim to fill the gap by providing a pipeline for new biopesticide or biological control products,” says Kathryn Bushley, principal investigator for the Minnesota Soybean Research & Promotion Council project and University of Minnesota assistant professor of plant and microbial biology.

“Profitability for Minnesota soybean farmers is the number one goal of the Minnesota Research & Promotion Council, which naturally leads to investing checkoff dollars in production research,” says Gail Donkers, soybean farmer from Faribault, Minnesota, and district director. “For every dollar invested in production research, a return of $9.42 is created. It is always exciting to see new research projects and proposals each year and to fund proposals that align with our goal of increasing demand for Minnesota soybeans and returning a greater profit on each bushel sold.”    

Bushley’s checkoff-funded research uses a set of top-candidate parasitic and toxin-producing fungi identified in previous research funded by the Minnesota soybean checkoff. The goal of this next-phase work is to translate the findings into viable biocontrol or bionematicide products. 

Objectives include performing bioactivity guided fractionation to chemically identify nematicidal and antifungal compounds in strains with high bioactivity, testing combinations of highly effective biological and chemical agents in greenhouse trials for activity against both pathogens, and then developing and testing seed treatments and spore formulation applications. 

“We were able to complete greenhouse trials last spring, but we were not able to get isolates out into the field for testing due to the pandemic,” she says. “We hope to do that this year. We have identified several fungi that seem to be highly effective in the greenhouse, more so than treatments such as Poncho VOTiVO, but these do need further testing in the field.”

Her analysis of laboratory-based testing of fungi against SCN can assist other researchers. It has been published in Phytopathology and a manuscript on plant bioassays is in the pipeline. 

“Overall, we hope to provide new information about important biological resources (fungi) and their chemical metabolites that can be managed by crop rotation or directly applied to field soil or soybean roots/seeds as a component of integrated management of SCN and SDS,” she says.

Published: Apr 5, 2021