More stripe rust possible in Willamette Valley
Stripe rust found in Oregon’s Willamette Valley last month may mean more is on the way, a researcher says.
“It is early to be finding stripe rust, so that may indicate we’re setting up for a bad stripe rust year,” said Mike Flowers, extension cereals specialist at Oregon State University. “In 2011, when we had the really bad stripe rust year, it was February before we found it. We’re basically finding it about a month earlier now.”
Last year, stripe rust appeared late, increasing the likelihood of the plant disease overwintering on volunteer plants or early-planted wheat, Flowers said.
He recommends growers check their fields and consider an early fungicide application with their herbicide spray, particularly if they’re growing a wheat variety that’s susceptible to stripe rust.
“I would say a lot of the varieties that people are growing are more resistant, but we do have a couple common varieties,” Flowers said. Stripe rust has been found on Goetze, Kaseberg and SY Ovation, he said.
Flowers isn’t particularly concerned about new strains of the disease.
“You never know you have one until you see it, so we definitely encourage people if they have a resistant variety, if they start seeing stripe rust on that variety, it’s important we as a group know about that so we can make sure everybody knows about it,” he said.
Rust in Western Oregon and Western Washington isn’t a surprise, said Xianming Chen, research plant geneticist for the USDA Agricultural Research Service in Pullman, Wash. Farmers in the western part of the region who see rust in their fields should spray to reduce the potential for its spreading, he said.
Chen is so far forecasting a moderate level of stripe rust across the Northwest, when susceptible wheat varieties experience roughly 38 percent yield loss. Chen bases his forecast on November and December weather conditions.
The most susceptible wheat varieties include Eltan, Xerpha, Tubbs 06 and ORCF-102, Chen said.
If the spring and early summer are dry and hot, stripe rust is not likely. But if weather conditions are cool and wet, yield loss can increase, Chen said.
Farmers in Idaho, Eastern Oregon and Eastern Washington need to begin checking their fields in March, Chen said.
Stripe rust has also been reported in Louisiana, Arkansas and Texas. When stripe rust is reported in Texas and Louisiana before March, it is likely to be significant in the Great Plains, he said. Warmer weather means the south-central states could likely see a severe stripe rust outbreak that could move north and east.
Chen plans to release a new stripe rust forecast in early March.