Above: LSU AgCenter wheat breeder Stephen Harrison discusses wheat variety trials with attendees of the 2023 wheat and oat field day at the LSU AgCenter Macon Ridge Research Station in Winnsboro. Photo by V. Todd Miller. Below: An example of Hessian fly pupae. Photo provided by Stephen Harrison.
In 2022, wheat prices rose due to drought and the war in Ukraine. This year, wheat prices remain high, and Louisiana producers are again taking an interest in planting the grain crop in 2023.
According to AgCenter statistics, producers planted about 45,000 acres of wheat in Louisiana during the past year, which is a substantial increase from the 14,000 acres of the previous season.
“There’s a significant amount of interest in wheat varieties right now because wheat prices are higher due to drought and the war in Ukraine,” LSU AgCenter small grains expert Stephen Harrison said.
Harrison is a 38-year veteran of harvest seasons at the AgCenter, where he works to improve wheat and oat varieties. He collaborates with breeders and research programs in several southern states through SunGrains, a seven-university wheat breeding cooperative he coordinates that shares genetic material, genomics knowledge, testing resources and royalties from seed sales.
“Proper variety selection determines whether farmers can capitalize on high wheat prices,” Harrison said. “This year, a big increase in wheat acres and a warm winter were associated with major Hessian fly damage across southern Louisiana, Texas, Mississippi, Alabama and Georgia.”
According to Harrison, Hessian flies haven’t been observed in Louisiana in the past for a number of years but may be a recurring problem for growers in the state going forward given the trend toward warmer winters.
Hessian flies lay eggs inside of young wheat between the stem and leaf sheathes, and the hatched larvae stunt tillers and create a patchy, dwarf look in fields. Longer periods of warmer temperatures in the late fall and winter allow the insects to complete multiple generations of reproduction and build up substantial numbers in fields. Yield of fields with heavy Hessian fly infestations were significantly reduced and some fields were abandoned as a result.
This year, Harrison said, the breeding team was able to collect good data on resistance of breeding lines in Baton Rouge, adding that variety resistance coupled with insecticidal seed treatment is the best way of preventing Hessian fly infestation. Major resistance genes characterized and incorporated by SunGrains breeders prevent infestation or limit its spread. SunGrains breeding lines from the seven collaborating universities will be screened for resistance this winter in a field that was managed over the summer to preserve viability of over-summering Hessian fly.
As far as variety resistance to the pest goes, Harrison said two years ago, AgSouth Genetics licensed AGS 3022, a wheat variety developed by the LSU AgCenter breeding team using methods that can bring new wheat varieties to market more quickly. The variety has excellent test weight and very high yields, he said, and is resistant to the Hessian fly. It also has a strong resistance to stripe rust and to fusarium head blight, or scab.
“Scab continues to be our biggest nemesis and what we spend a large proportion of our resources on,” Harrison said.
In most cases, new wheat varieties take 10 years to develop from the time breeders first make a cross between existing lines to the day the seed becomes available for farmers. However, AGS 3022 was released in six years. Harrison and his team used a time-saving procedure, the double haploid methodology, which is a breeding shortcut used in some cases to speed up the process.
“It’s a very expensive process, so we can’t do that with our entire breeding program” Harrison said. “It would take an additional half a million dollars to do that on every cross we make, but we do choose a few high-priority crosses each year.”
A new wheat breeder, Noah DeWitt, has been hired by the LSU AgCenter and will help lead the breeding program going forward, taking over the wheat and oat breeding program when Harrison retires.
Under DeWitt’s guidance, a joint initiative will focus on introducing large-scale genetic and drone data into developing improved oat varieties for use as forage, and increased efforts will be placed on developing triticale varieties for cover cropping.