1. Dep. of Agronomy; Iowa State Univ.; 1208 Agronomy Hall Ames IA 50011-1010
2. USDA-ARS Plant Science Research Unit, Dep. of Crop Science; Box 7620 North Carolina State Univ.; Raleigh NC 27695-7620
3. Pathology & Entomology Specialists; Pioneer Hi-Bred Int., Inc.; 7301 NW 62nd Ave., PO Box 85 Johnston IA 50131-0085