Computer Monitors Changing Rust Risk in WheatBy Ben Hardin
May 1, 1997
Recent weather has been giving a workout to a computer model that predicts the severity of leaf rust fungi in this year's Central Great Plains wheat crop.
The predictions are vital to growers, who must decide in the next few weeks whether the rust threat is severe enough to justify the costs of fungicide applications on their crops. Next week, more numbers will be plugged into the model to assess potential wheat yield losses.
In late March, the computer model--nicknamed "Rusty"--warned of potential yield losses of up to 30 percent in some fields of susceptible wheat varieties in Kansas and Oklahoma. The picture changed with early April's freezing weather that thwarted fungi, but also stunted wheat so much that many fields may have to be plowed under to make way for other crops.
Merle Eversmeyer, a plant pathologist of USDA's Agricultural Research Service at Manhattan, Kan., will visit southern Texas soon to check wheat there for fungal spores that could hitch a ride northward on the wind.
Eversmeyer and his colleagues at Kansas State University, Manhattan, developed "Rusty" to help wheat growers make management decisions in both spring and fall. At 2-week intervals throughout the crop year, the model uses new weather information and field observations on rust spore survival to sharpen its predictions of rust outbreaks in wheat.
An article about the computer model appears in the April issue of Agricultural Research magazine. The article can be viewed on the World Wide Web at:
Scientific contact: Merle G. Eversmeyer, USDA-ARS Plant Science and Entomology Research Unit, U.S. Grain Marketing and Production Research Center, Manhattan, Kan., phone (785) 532-6168, fax (785) 532-6167, firstname.lastname@example.org.