Two new varieties of winter wheat that will help farmers battle the Russian wheat aphid while increasing yields are being released this week. The two new varieties, developed by Colorado State University Agricultural Experiment Station, will be available to seed growers through the Colorado Wheat Research Foundation for next year’s crop.
The new varieties, Hatcher and Bond CL, offer farmers high-yielding choices compared to other Russian Wheat Aphid-resistant varieties developed by the university in previous years. One of the varieties also carried tolerance to Beyond herbicide, which allows growers to selectively control winter annual grassy weeds.
"The combination of traits these varieties offer can help growers increase their profits while decreasing their use of insecticides," said Scott Haley, Colorado State wheat breeder.
Hatcher is a hard red winter wheat variety with a high yield. It has properties that make it excellent for milling into flour and for bread baking. It is resistant to the original biotype of the Russian wheat aphid, and can replace previous varieties developed by Colorado State such as Prairie Red and Yumar, because it has a higher yield.
Bond CL also is a hard red winter wheat with a high yield. It also is resistant to the original biotype of the Russian wheat aphid and is variety that is ideal for bread baking. This variety also is tolerant to Beyond herbicide because it contains the Clearfield gene. This resistance is developed through traditional breeding practices and not through transgenic technology. With this gene, growers can control weeds such as jointed goatgrass, cheatgrass, downy brome and feral rye with Beyond herbicide.
Colorado State University previously released a wheat variety, called Above, with the Clearfield gene. This variety was the first publicly developed variety in the nation to contain the Clearfield gene. Bond CL has yields comparable to Above, but vastly improved traits for a quality baking wheat and Russian wheat aphid resistance.
Hatcher and Bond CL were developed by a team of researchers funded by the university’s Agricultural Experiment Station. The team was led by wheat breeder Scott Haley and included Jerry Johnson, Cooperative Extension agronomist and coordinator of the university’s statewide crop testing program, and Frank Peairs, Cooperative Extension entomologist.
These new varieties carry resistance to the original strain of Russian wheat aphid, but not to new strains identified in 2003 and 2004.
"Because growers do not know which strain could pose a problem for their crops, varieties with resistance to the original strain continue to be an effective means to minimize risk of damage from the aphid," said Haley.
The original strain of the aphid entered Colorado in 1986. Since then, it has cost the state’s 14,000 wheat farmers more than $132 million in crop losses and insecticide control efforts. In Colorado, 4.7 million acres has had to be treated with insecticides to control the aphid since 1986, which means that 30 percent of the total wheat acreage in the nation has been treated.
The Russian wheat aphid affects the growth of the young wheat plant and prevents the leaves from unrolling. They live in tubes formed by the rolled leaves, making it difficult to control them with predatory insects and insecticides. The insect, which can survive through the winter, feeds on the wheat grain and plants.
The new strain or biotype of the Russian wheat aphid began damaging wheat crops in Colorado last year before harvest. Since then, other biotypes, or slightly different strains of the insect, have been discovered in Colorado. Colorado State is currently working on developing new wheat varieties with to resistance to the newer Russian wheat aphid biotypes.
In an agreement between Colorado State, Colorado Wheat Research Foundation and Colorado Seed Growers Association, Hatcher and Bond CL seed may be grown and sold only as a class of certified seed by Colorado Seed Growers Association members licensed by the Colorado Wheat Research Foundation. The foundation will obtain a certificate of plant variety protection for these new varieties under the federal Plant Variety Protection Act. Royalties paid to the foundation by certified seed growers from the sale of these varieties is returned to Colorado State University to support continued research and variety development.
For more information about this story and other agricultural related news at Colorado State University, visit www.agnews.colostate.edu.