Clearfield®Wheat Variety Released
New, non-transgenic herbicide-tolerant variety developed by Colorado State University will facilitate weed management.
A new hard red winter wheat variety, named Above, which incorporates the Clearfield® herbicide resistance technology, was released to seed producers by Colorado State University Agricultural Experiment Station researchers in August 2001. Above is the first wheat variety developed in the Great Plains that, when used in conjunction with imidazolinone herbicide, will allow selective control of several key grass (e.g., jointed goatgrass, brome, cheat, and feral rye) and broadleaf weeds in wheat. Prior to the development of this new technology, producers had few if any viable options for control of some of these economically devastating weeds. Certified seed of Above should be available for planting in fall 2002.
Scientists at BASF (then American Cyanamid) discovered the gene that confers tolerance to imidazolinone herbicide in wheat in the early 1990s. Clearfield® wheat was developed through a commonly used breeding technique known as seed mutagenesis, a process by which the function of a key enzyme in the plant (acetohydroxyacid synthase, or AHAS) was altered to allow continued wheat plant growth and development following herbicide treatment. While the Clearfield® technology is relatively new to wheat, it has already been commercialized in both corn and canola and is currently under development in rice, sugarbeets, and sunflower.
The availability of Clearfield® wheat represents a unique partnership between public-sector wheat breeding (CSU) and a private interest (BASF) that holds a U.S. patent on a commercially viable biotechnological product. As with other recent CSU wheat variety releases, ownership of Above was transferred to the Colorado Wheat Research Foundation, which has agreements in place with BASF to foster the promotion and intellectual property protection of Clearfield® wheat. Other important aspects of Clearfield® Wheat include the following:
- Because no foreign DNA was transferred, Clearfield® wheat is non-transgenic (i.e., not genetically engineered and not considered “genetically modified”). Producers will experience no barriers in either domestic or overseas markets.
- Potential exists for herbicide resistance to develop in weed populations either by artificial selection or by transfer of the tolerance gene by outcrossing to jointed goatgrass.
- Stewardship programs, designed to forestall herbicide resistance development in weed populations, will focus on promotion of crop and herbicide rotations and requirements for purchase of certified Clearfield® wheat seed for production of each commercial crop. The use of “farmer-saved” or “bin-run” seed will be prohibited.
Society and consumers have expressed various concerns over the development and use of transgenic crop plants. Although Clearfield® Wheat is non-transgenic, herbicide resistance that is transgenic (e.g., Roundup Ready® wheat) is currently under development by Monsanto in partnership with various university and private wheat breeding programs. If domestic and foreign marketing concerns are resolved, Roundup Ready® spring wheat could be available in the U.S. and Canada by 2003. Most university and private winter wheat breeding programs in the Great Plains region are also working with Monsanto on Roundup Ready® wheat, but this effort lags far behind the efforts already expended in the spring wheat producing areas.
