1. North Dakota State University, Department of Plant Sciences, Cereal Science Graduate Program, Fargo, ND, U.S.A.
2. USDA-ARS, Red River Valley Research Center, Cereal Crops Research Unit, Hard Red Spring and Durum Wheat Quality Laboratory, Harris Hall, North Dakota State University, Fargo, ND 58108, U.S.A.
3. North Dakota State University, Department of Plant Pathology, Fargo, ND, U.S.A.
4. USDA-ARS, Cereal Crops Research Unit, Fargo, ND 58102, U.S.A.