Study: Wheat Resistance Genes Failing

Many of the genes that allow wheat to ward off Hessian flies are no longer effective in the southeastern United States, and care should be taken to ensure that resistance genes that so far haven’t been utilized in commercial wheat lines are used prudently, according to U.S. Department of Agriculture and Purdue University scientists.

An analysis of wheat lines carrying resistance genes from dozens of locations throughout the Southeast showed that some give little or no resistance to the Hessian fly, a major pest of wheat that can cause millions of dollars in damage to wheat crops each year. Others, even those considered the most effective, are allowing wheat to become susceptible to the fly larvae, which feed on and kill the plants.

Wheat resistance genes recognize avirulent Hessian flies and activate a defense response that kills the fly larvae attacking the plant. However, this leads to strains of the fly that can overcome resistant wheat, much like insects becoming resistant to pesticides.

“The number of genes available to protect wheat is limited. There really aren’t that many,” said Richard Shukle, a research scientist with the USDA Agricultural Research Service Crop Production and Pest Control Research Unit and Purdue adjunct associate professor of entomology. “In the Southeast, having multiple generations of Hessian fly each year enhances the ability of these flies to overcome wheat’s resistance.”

Sue Cambron, a USDA Agricultural Research Service research support scientist, received Hessian flies from 20 locations in Alabama, Georgia, North Carolina, South Carolina and Louisiana and used them to infest 21 varieties of wheat that each contained different resistance genes, most of which have been deployed in commercial wheat, and a few that haven’t yet. While the study did not include all of the 33 named resistance genes, it did show that only five of the 21 genes evaluated would provide effective resistance to flies in the Southeast, and none was effective in all the Southeast locations.

“Even some of the newer genes that haven’t been deployed in cultivars weren’t too effective,” Cambron said.

That’s because flies have likely interacted with, and adapted to, those genes already, said Brandi Schemerhorn, a USDA-ARS entomologist and Purdue assistant professor of entomology. She said it’s possible that some of the genes were introduced to flies unintentionally in plots where wheat cultivars with those genes were being tested for suitability to Southeast climates. The resistance genes also could have come from other plants, such as rye, and the flies may already have started to overcome those genes.

Schemerhorn said she suspects a certain number of flies in any population have the ability to overcome any wheat resistance gene, which defends against the flies’ ability to feed on the plant and starves the insect larvae. When a resistance gene kills off some of the flies, the survivors breed and eventually establish a population that renders the gene ineffective.

“We’re creating a system in which the fly is becoming more virulent,” Schemerhorn said. “What we have to do is slow down that adaptation or virulence.”

Shukle and Schemerhorn suggest stacking genes in a wheat cultivar. There are only a few genes that haven’t been deployed, and they believe combining two of those would be the best option.

“With a small number of identified resistance genes, we can’t afford to release wheat lines with only one resistance gene,” Shukle said. “If you deploy two different resistance genes, it’s unlikely that a population of flies could overcome both of them.”

Schemerhorn is working to combine two of the unreleased genes for testing with Hessian fly populations.

The USDA funded the research. Shukle, Schemerhorn and Cambron collaborated with David Buntin, a University of Georgia professor of entomology; Randy Weisz, a North Carolina State associate professor of crop science and small grains specialist; Kathy Flanders, an Auburn University associate professor of entomology; and Jeff Holland, a Purdue associate professor of entomology. Their findings were published in the Journal of Economic Entomology.

Leave a Reply

Seed/Biotech Stories

Syngenta Seedcare Institute
Seed/BiotechSyngenta Opens New North America Seedcare Institute In Stanton, MN
September 23, 2016
Syngenta unveiled its new Seedcare Institute in Stanton, MN, during a recent grand opening celebration. More than 150 industry leaders, Read More
Corn close up
Crop InputsNY Times: Bayer-Monsanto a Bad Deal for Farmers
September 15, 2016
Via NY Times: Don Halcomb, a 63-year-old farmer in Adairville, KY, is expecting his profit to vanish this year, largely Read More
Seed/BiotechAgrisure Trait Stack Approved For Above-Ground Corn Insect Control
September 12, 2016
Agrisure 3120 E-Z Refuge, a new trait stack from Syngenta, has received registration approval from the EPA. Agrisure 3120 E-Z Read More
Monsanto sign
Crop InputsBayer Ups The Ante On Monsanto Offer
September 6, 2016
Bayer AG says talks with Monsanto Co. have advanced, and it is now willing to offer more than $65 billion, Read More
Trending Articles
Corn Field
Eric SfiligojFacing Ag Industry Challenges
September 26, 2016
At the 2016 annual Mid America CropLife Association (MACA) meeting in September, a pair of crop protection company representatives discussed Read More
Bayer Monsanto
Crop InputsBayer-Monsanto Mega-Merger: 6 Things You Need To Know
September 14, 2016
Mega mergers have become almost routine in the agricultural industry. Right on the heels of Monday’s news that fertilizer giants Potash Read More
Potash Corp Agrium
Crop InputsAgrium, Potash Corp To Merge To Create $36 Billion Company
September 12, 2016
Canada’s Agrium Inc. and Potash Corp of Saskatchewan Inc. have agreed to combine in a deal that would create a Read More
Osage Co-op Elevator Osage, IA Finished Building
OpinionAre We Crazy?
September 8, 2016
At some point in the first few months of my employment here at CropLife® magazine, I started getting curious about Read More
ManagementMAGIE 2016 Highlights and Deere Anti-Trust
September 1, 2016
CropLife Editor Eric Sfiligoj discusses the recent Midwest AG Industries Exposition and the Department of Justice’s objection to John Deere Read More
ASMARK 2016 Retailers Live! Tour - CPS
CropLife 100CPS Acquires Texas Retail Operation
August 23, 2016
Crop Production Services (CPS) has acquired the assets of Larry’s Chemical and Spray, Inc., for an undisclosed amount in an Read More
Latest News
Young Corn Field
StewardshipStudy: Ohio Farmers Doing ‘A Good Job Of Managing…
September 27, 2016
Leaders from Ohio’s largest grain farming organizations announced today that Ohio farmers are doing their part in effectively managing phosphorus Read More
Growmark FS Outlet
Industry NewsGROWMARK To Purchase Suncor’s Share Of UPI
September 26, 2016
GROWMARK and Suncor have reached an agreement in which GROWMARK will purchase Suncor’s 50% interest in UPI, Inc. in Ontario, Read More
Corn Field
Eric SfiligojFacing Ag Industry Challenges
September 26, 2016
At the 2016 annual Mid America CropLife Association (MACA) meeting in September, a pair of crop protection company representatives discussed Read More
Syngenta Seedcare Institute
Seed/BiotechSyngenta Opens New North America Seedcare Institute In …
September 23, 2016
Syngenta unveiled its new Seedcare Institute in Stanton, MN, during a recent grand opening celebration. More than 150 industry leaders, Read More
StewardshipMonsanto Invests $1.6 Million In System To Quantify Gre…
September 23, 2016
The USDA – Natural Resources Conservation Service (USDA-NRCS) recently awarded the National Corn Growers Association (NCGA) and its Soil Health Read More
Pipe rack
LegislationCourt Sides With Ag Retailers On PSM
September 23, 2016
The D.C. Court of Appeals has ruled the Occupational Safety and Health Administration violated the Occupational Safety and Health Act when Read More
ManagementPacific Coast Fertilizer Announces Interest In Longview…
September 22, 2016
Pacific Coast Fertilizer LP (PCF) announced at the Cowlitz Economic Development Council board of directors meeting its interest in developing Read More
Young corn plants in soil
UncategorizedCool Planet Raises Additional $9 Million To Commerciali…
September 22, 2016
Cool Planet has announced the first close of a new financing round to commercialize the company’s Cool Terra Engineered Biocarbon Read More
Crop InputsJim Loar Promoted To President And CEO Of Cool Planet
September 22, 2016
In a move that reflects and reinforces the company’s commitment to the agricultural market, the Cool Planet board of directors Read More
BlendersNorth Dakota Coop Debuts Dry Fertilizer Plant
September 22, 2016
North Central Grain Cooperative has begun operations at a new dry fertilizer plant at its Rolla, ND, site. It is Read More
Crop InputsMonsanto, Bayer Officials Defend Proposed $66 Billion M…
September 21, 2016
Top officials for Monsanto and Bayer defended their proposed $66 billion merger before skeptical senators on Tuesday, insisting that the Read More
ManagementUpcoming Shows & Recent Events
September 19, 2016
Editors Paul Schrimpf and Eric Sfiligoj talk about upcoming trade shows and events and review the Mid America CropLife Association Read More
Industry NewsVerdesian Life Sciences Appoints New CEO
September 19, 2016
Verdesian Life Sciences, a plant health and nutrition company, today announced that its board of directors has named Kenneth M. Avery Read More
Corn
Crop InputsEPA Settles With Syngenta For Alleged Multi-Regional Pe…
September 19, 2016
The U.S. EPA has announced a multi-region settlement with Syngenta Crop Protection, LLC (Syngenta) in Greensboro, NC, for alleged violations of Read More
ManagementMerger Mania
September 16, 2016
Editors Paul Schrimpf and Eric Sfiligoj discuss this week’s mega-ag mergers of Bayer and Monsanto and Potash and Agrium. Read More
Monsanto sign
Crop InputsMonsanto Ends Up Being A Bargain For Bayer
September 16, 2016
History will say Bayer got a bargain in its $66 billion purchase of Monsanto, writes David Nicklaus, St. Louis Post-Dispatch. The Read More
Greg Musson, Gar Tootelian
CropLife 100California Ag Retailer Steps Up To Feed Families Affect…
September 16, 2016
GAR Tootelian, Inc. (GAR) in Reedley, CA, is challenging the Central Valley to help raise enough money and provide 525,000 meals Read More
Crop InputsBayer, Monsanto CEOs Discuss Merger
September 15, 2016
Werner Baumann, Bayer CEO, and Hugh Grant, Monsanto CEO, discuss why they decided to merge their companies. Read More