1. North Dakota State University, Department of Plant Sciences, P.O. Box 6050, Department 7670, Fargo, ND 58108-6050, U.S.A.
2. USDA-ARS, Cereal Crops Research Unit, Hard Red Spring and Durum Wheat Quality Laboratory, Harris Hall, North Dakota State University, Fargo, ND 58108, U.S.A.