1. United States Department of Agriculture, Agricultural Research Service, Crop Production and Pest Control Research Unit, West Lafayette, Indiana 47907 (S.R.S., A.S.B.); Department of Agronomy, Purdue University, West Lafayette, Indiana 47907 (S.R.S., A.S.B.); and Department of Plant Pathology, Throckmorton Plant Sciences Center, Kansas State University, Manhattan, Kansas 66506 (L.H., B.S.G.)