What is in this article?:
- Herbicide-resistant wheat varieties tested in Virginia
- Versatile material
• Clearfield wheat isn’t exactly new. BASF began working with the system back in the 1980s and the first Clearfield varieties were released nearly a decade ago. Clearfield wheat is tolerant to the herbicide Beyond. The first Clearfield wheat variety was called Above. Above and Beyond was a good marketing ploy, but has been slow to be accepted by Virginia farmers.
Beyond is labeled to control a wide range of weed pests common to wheat production in the upper Southeast. Italian ryegrass and wild oats are among the grasses it controls. It can control chickweed, henbit and other mustard species and suppresses and may control a number of other broadleaf weeds, including lambsquarters and pigweed.
The weed species controlled or suppressed by Beyond provides some interesting fits for Virginia growers, Thomason says.
If a grower has a field with a history of Italian ryegrass problems, Clearfield may be a good fit. Or, if a grower has chickweed that is resistant to Harmony, that would be another good fit, Thomason says.
Another scenario that may fit is for farmers who would like to grow a rye cover crop, but don’t do it because they are growing small grains. This material can take the ryegrass out and make a rye cover crop more feasible.
This herbicide doesn’t have full residual activity. That may create some problems with lambsquarters. That’s something we will have to keep an eye on when we get farther along with the Clearfield program, Thomason stresses.
“We thought we had something that would work 4-5 years ago with the product. At that time there was only one known gene with the tolerance needed for wheat. About the time Carl Griffey had a variety he thought would work, they found a second tolerant gene, so he started over again,” Thomason says.
“With the single gene we were still getting some herbicide damage to wheat. With the second gene, herbicide damage has virtually gone away. For example, damage rating using the same wheat variety and a double rate of Beyond herbicide were 5 for one gene and less than 1 for two genes.”
Thomason showed the farmers in attendance a plot of Jamestown wheat that did not contain the herbicide mutation gene and was sprayed with Beyond. There was one plant left alive in the plot. The first gene eliminated about 95 percent of the damage and two genes virtually eliminated plant damage in the Virginia tests.
How rapidly the Clearfield technology is accepted and put into use by Virginia farmers will likely depend on how well it works in higher yielding wheat varieties and how it fits into individual farming operations.