
Computer
Monitors Changing Rust Risk in WheatBy Ben Hardin May 1, 1997Recent 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: http://www.ars.usda.gov/is/AR/archive/apr97/rusty0597.htm 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,
[email protected]. U.S. Department of Agriculture | |