Black Stem Rust Ug99

Puccinia graminis f. sp. tritici

^{Photo by Mary Burrows, Montana State University, Bugwood.org}

Survey Information

Black stem rust (Ug99) Puccinia graminis f.sp. tritici (Ug99) is a serious disease of wheat and barley. While wheat in the United States is resistant to most strains of black stem rust, it is not resistant to this strain which has shown up in eastern Africa and the Middle East. Black stem rust (Ug99) can cause 80-90% grain loss in infected crops.

The Wyoming Black Stem Rust (Ug99) Survey is conducted by the Wyoming Pest Detection /CAPS Program. Wheat and barley fields are visually surveyed throughout the growing season. Any suspect material found is sent to the University of Wyoming for further identification. Some fields are selected for a more intensive sampling effort, where twenty plants are randomly selected from each field for further examination at the University of Wyoming.