A study at the University of Saskatchewan’s Crop Development Centre has identified two critical genes responsible for the bright yellow pigment in durum grain, a trait desired by foreign markets. The three-year study was a collaborative effort with the CDC durum program and the Agriculture and Agri-Food Canada durum breeding program at Swift Current. It was funded in part by the Endowment Fund, which is administered by Western Grains Research Foundation (WGRF).
“In durum wheat, the yellow color of the endosperm is highly desirable in the international markets. It produces a bright yellow pasta product, which our customers appreciate, so there’s an international demand for elevating the levels of yellow pigment in the durum endosperm,” says Dr. Curtis Pozniak, professor at the U of S and a durum wheat breeder at the Crop Development Centre.
“This project was designed to develop tools that Canadian breeders could use to select more efficiently for higher yellow pigment types, and to some extent understand the genetics behind pigment accumulation in the grain.”
“Once you understand the genes involved, you can develop some appropriate selection strategies to elevate pigment and to identify breeding and germplasm lines that can be used in crossing.” Contact with corn researchers provided hints to what genes might be used in pigment accumulation. Pozniak sequenced those genes, in search of genetic differences between high and low pigment durum lines.
“The first step was finding the genes and then finding differences in those genes between high and low pigment accumulators. When we had that information, we were able to develop and validate DNA-based markers for selection of elevated yellow pigment,” he says.
Pozniak sequenced two genes and was able to show those genes were associated with pigment accumulation in durum.
“That told us these markers and genes were involved. Once we had that solved, we evaluated these markers in a set of durum breeding lines and were able to show a NEWS RELEASE – for immediate release Page 1 of 2 reasonable correlation between different forms of this gene and pigment accumulation. That suggested these could be a target for markers when selecting durum wheat,” says Pozniak.
These markers are available to both programs and by using them in his current program, Pozniak says he has already seen examples of yellow pigments at higher levels than the current standards AC Navigator and Commander.
Graham Worden, senior manager, technical services with the Canadian Wheat Board in Winnipeg, says for yellow color, AC Navigator raised the bar to an extremely high level.
“It has one of the best bright yellow pigment values of any durum variety around the world. We have definitely improved the yellow pigment color of Canadian durum over the last few decades. But so has the competition. As we make improvements, so do they.”
Worden says Canada dominates the export market for durum wheat. The total annual world production of durum wheat is around 35 million tonnes and Canadian production is 4.5 to 5 million tonnes. But with most of that total available for export, Canada holds close to 60 percent of the world durum trade, typically around 8 million tonnes each year.
Pozniak has published three manuscripts in international journals, with a fourth on the way. He was invited to make a presentation at a prestigious international durum wheat symposium in Italy in 2008.
“The Western Grains Research Foundation has been a great partner with our breeding program. The dollars invested from the Endowment Fund has allowed us to focus on more upstream research that can then be applied to our breeding program. An important part of any plant breeding program is developing new and useful tools that can make the breeding process more efficient,” he says.
The Endowment Fund, the original core fund of WGRF, has supported more than 200 research projects since 1983. For more information on the project check the WGRF Web site at www.westerngrains.com.
