Breeders seek strains high in tocotrienols to open up new barley acreage

By JOHN O'CONNELL

Capital Press

ABERDEEN, Idaho -- Recent discoveries made at the USDA's Small Grains and Potato Germplasm Research Unit could speed development of improved cold-tolerant barley lines and eventually expand the crop's winter production in Idaho.

While examining data on winter and spring barley varieties in a USDA laboratory in Wisconsin, former Aberdeen USDA research geneticist Eric Jackson noticed winter varieties were high in tocotrienols, members of the vitamin E family.

He asked fellow Aberdeen geneticist Becky Oliver to research the genetic sequence of HGGT -- an enzyme that helps assemble tocotrienols -- in a barley population she'd already been using to study vitamin E.

"People think of vitamin E as an antioxidant. They don't think of it as a cold-tolerance gene," Oliver said. "(Jackson) thinks the tocotrienols act as a protection mechanism to defend plant tissue against cold."

By comparing the sequences she identified, Oliver developed a marker for HGGT, which should help breeders promptly identify plants with the desirable vitamin E trait.

"If you have markers ... it really speeds up breeding by eliminating the undesirable types before you have to do field trials," Oliver said.

Oliver has also identified important sites within the gene's promoter, which determines the extent to which a gene is expressed.

She said new cold-tolerant lines could be developed, or cold tolerance could be incorporated into proven lines.

Based on the work by Oliver and Jackson, Gongshe Hu, barley breeder with the USDA facility, intends to start testing barley lines this year for cold tolerance.

"If they do show those kinds of cold-tolerance preferences, we will incorporate them into our winter barley breeding program," Hu said.

Nonetheless, resulting varieties could still be a decade away from commercial availability, Hu said.

"This is an interesting area we'd like to look at. Right now we are trying every effort we can to speed up the breeding process," Hu said.

Idaho's winter barley production is now confined to the Magic Valley, said Kelly Olson, administrator of the Idaho Barley Commission.

"That leaves a lot of the rest of the state not adapted to these varieties. Winter barley provides a lot of flexibility to the producer to be able to plant it in the fall," Olson said. "The research at Aberdeen, we believe, is really going to accelerate the pace we can release new varieties adapted to eastern Idaho winter conditions."

Oliver has also identified a genetic mutation in another Aberdeen barley line that could lead to development of seed that helps fight cancer.