The Hessian fly, one of the most serious pests of small grain crops worldwide, poses a significant threat to winter wheat grown in the eastern United States. Clemson University scientists are leading efforts to combat this issue.
Richard Boyles, a cereal grains breeder, and Francis Reay-Jones, an entomologist, both stationed at the Clemson Pee Dee Research and Education Center (REC) in Florence, are spearheading a study to improve Hessian fly resistance in winter wheat germplasm.
This research supports the mission of Clemson’s Advanced Plant Technology Program and is part of a broader effort across the southeastern U.S. Similar research trials are ongoing at Louisiana State University, Texas A&M University and the University of Georgia.
“For this study, we will use molecular markers to track wheat genes resistant to the Hessian fly,” Boyles said. “At present, genetic resistance to Hessian fly often relies only on a single gene, which poses a risk to the insect pest overcoming resistance. Our goal is to provide wheat with multiple mechanisms of resistance. Increasing durability of this crop to Hessian fly attack is becoming more critical as warm periods during the winter months are leading to additional Hessian fly life cycles.”
More frequent life cycles result in more flies and larvae that increase crop damage for wheat farmers.
This study aims to provide information to guide grower decisions, combine genotyping and field screening to improve resistance, identify additional sources of resistance and integrate new resistance genes to develop high-yielding, resistant wheat varieties.
Newly developed wheat lines will be tested at nurseries and in statewide variety trials. Information about this study will be highlighted at the Small Grains Field Day on April 30, at the Pee Dee REC, 2200 Pocket Road, Florence, South Carolina 29506.
Hessian fly management
With the Southeast’s warm climate, up to six generations of Hessian fly can occur per season.
The Land-Grant Press article, Management strategies for Hessian fly in wheat, written by Reay-Jones and University of Georgia entomologist G. David Buntin, shows researchers have identified 37 wheat genes resistant to Hessian fly.
“However, resistant varieties often lose effectiveness as the pest adapts,” Reay-Jones said. “Outbreaks can occur on wheat previously classified as resistant. Therefore, identifying novel resistance genes and releasing varieties with these new resistance genes will help to reduce yield losses and provide environmentally friendly management solutions.”
Adult Hessian flies live for one to four days. Females, reddish-brown and about 1/8 inch long, lay 250 to 300 eggs on wheat leaves. Males are brown or black and about 1/10 to 1/8 inch long. Depending on temperature, eggs hatch in three to 12 days. Feeding lasts 14 to 30 days under variable conditions.
Control options include planting resistant varieties and using insecticide seed treatments.
Wheat is the fourth highest row crop planted in South Carolina, behind soybeans, corn and cotton. According to the U.S. Department of Agriculture’s 2023 State Agriculture Overview, South Carolina planted 110,000 acres of wheat in 2023, yielding a production value of $33.3 million. Soybeans led with 395,000 acres, corn had 365,000 acres and cotton came in at 210,000 acres.
Source : clemson.edu