Rust resistance key to organic wheat survival
Updated: Friday, August 05, 2011 10:38 AM
Organic growers have few preventive or spray options
By MATTHEW WEAVER
EDWALL, Wash. -- Organic wheat growers in the Pacific Northwest are concerned about stripe rust, an epidemic for which they have few treatment options.
Oregon State University wheat breeder Mike Flowers said most organic growers were hit by the stripe rust "pretty hard," but losses vary depending on the variety of wheat they grew. He said loss of quality and yield will be an issue.
Corvallis, Ore., farmer Clinton Lindsey, farm manager of A2R Farms, said one of his best red wheat fields was "completely devastated" by the rust. He planted 45 acres of red wheat and 30 acres of white wheat, with 25 acres being hit hard.
"We're not really in a position to purchase organic fungicide," Lindsey said. "We were adopting a kind of preventive approach, but it didn't work as well."
They used several applications of compost tea in the spring and winter, but the weather didn't cooperate, Lindsey said. They used the same plan last year and only had a touch of stripe rust, he said.
There aren't many options available to organic producers, researchers and farmers say.
"Pray or not pray," said Owen Jorgensen, a Coulee City, Wash., farmer, who is on the northern edge of the stripe rust region.
Jorgensen's 100 acres of organic wheat held up well, even though one field is a half-mile away from a conventional fields that needed spraying.
In the future Flowers said farmers could vary planting dates or less-frequent irrigation, as the moisture helps the rust germinate. Planting winter wheat later helps to avoid many possible disease issues, he said.
Farmers could also go to a variety with better disease resistance. Many grow spring wheat, Flowers said, and if kernels don't get too soft or shrunken, a little stress actually helps the plant make protein. Hard red spring wheat tends to hold up better against rust compared to soft white spring wheats.
Stephen Jones, director of the Washington State University research and extension center in Mount Vernon, Wash., said there aren't many options. Jones breeds wheat for organic systems.
This year, most resistances aren't great due to the cool, damp weather conditions, Jones said, but several varieties look good on the western side of Washington. They include Bauermeister, MDM, Norwest 553 and club wheats Cara and Bruehl.
Jones advised farmers to attend field days at research farms to look for themselves at what's being worked on. He advised against bringing untested varieties in from outside the region.
Pat Hayes, professor and barley breeder at Oregon State University, said new, resistant barley varieties from his program include Alba and Streaker. Hayes also spoke of the need for genetic diversity, with resistant varieties possessing different resistance mechanisms.
"Rust never sleeps," Hayes said. "Even though we have resistance in our varieties that is effective now, you don't want to rely on that forever."
Not all growers are concerned.
Seth Williams said the epidemic of stripe rust that's had conventional farmers spraying their fields this year isn't cause for alarm by itself.
Williams is more worried about the potential for chemical drift from other fields. He tries to keep tabs on which fields are sprayed and when, he said. If the spray gets on his fields, it could mean a loss of the entire field in organic production for at least a year, he said.