Stripe rust developing in PNW

Farm and Ranch February 22, 2011 Last year was a severe one for stripe rust in wheat in the Pacific Northwest and that meant that last fall;

Chen: “The rust spores are quite high nowadays in our region.”

Xianming Chen of the USDA’s Agricultural Research Service in Pullman speaking last fall. Now in a new update Chen states that stripe rust is already awake in the PNW, much earlier than last year. He says the rust survived the winter with the help of the widespread snow cover in the cold spell of early December.

Oregon scientists reported rust pustules in a wheat field near Pendleton on the first of February. The disease was also easily found in Willamette Valley wheat fields.

Chen says he found sporulating rust in several fields in Washington’s Horse Heaven Hills last week, even in fields where plants were still small and stripe rust was not found in November.

The ARS scientist says rust will develop fast when the weather warms, when night temperatures are in the 40 degree range and day temperatures are into the 50s. Chen says early application of fungicides will be better for fields planted with susceptible and moderately susceptible varieties. He says if stripe rust is found when the temperatures warm consider spraying with a fungicide even before herbicide application. Chen adds that even if no rust is found, based on last year’s experience, susceptible or moderately susceptible varieties should be sprayed with a fungicide when herbicides is applied. He also suggests using a fungicide at full rate as the rust is active and the season will likely be very long.

I’m Bob Hoff and that’s the Northwest Farm and Ranch Report on Northwest Aginfo Net.

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