Submitted to: Wheat Newsletter
Publication Type: Research Notes
Publication Acceptance Date: 5/1/2004
Publication Date: 7/13/2004
Citation: Chen, X., Ling, P., Wood, D.A., Moore, M.K., Pahalawatta, V. 2004. Epidemiology and control of wheat stripe rust in the united states, 2003. Wheat Newsletter. 50:274-277. Interpretive Summary: Wheat stripe rust, leaf rust, and stem rust were monitored throughout the Pacific Northwest (PNW) using trap plots and field survey. The diseases were accurately predicted for the PNW in 2003 using monitoring data and predictive models based on environmental factors such as temperature, precipitations, and resistance of wheat cultivars. Through cooperators in many other states, wheat stripe rust was monitored throughout the United States. In 2003, wheat stripe rust occurred in more than 25 states from Washington State to Florida and from Texas to Ontario, Canada. Severe yield losses caused by stripe rust occurred in the PNW, California, Texas, Louisiana, Arkansas, Oklahoma, Kansas, Nebraska, Colorado, and South Dakota. In 2003, stripe rust epidemic caused wheat yield losses of 88.88 million bushels plus multi-million dollars on fungicide application in the United States.
Technical Abstract: In 2003, wheat stripe rust, leaf rust, and stem rust were monitored throughout the Pacific Northwest sing trap plots and field survey. Through cooperators in many other states, wheat stripe rust was monitored throughout the US. Yield losses caused by stripe rust were estimated about 88.88 million bushels. Without fungicide applications, the damage would be much greater. More than 400 wheat stripe rust samples throughout the US were tested to determine their virulence and identify races of the pathogen. From the samples, 25 previously identified and 13 new races were detected. We evaluated more than 13,000 wheat germplasms and breeding lines for resistance to stripe rust. The wheat entries also were evaluated for resistance to leaf rust, powdery mildew, and physiological leaf spot in field sites where these diseases occurred naturally. Germplasms and breeding lines with resistance to the disease especially stripe rust were identified. We have determined genetics of resistance in some of the sources, developed molecular markers for several stripe rust resistance genes. A bacterial artificial chromosome (BAC) library was constructed for cloning stripe rust resistance genes. New fungicides were tested for control of stripe rust.