1. Department of Crop Sciences; University of Illinois Urbana-Champaign; 3-320 Tuner Hall; 1102 S. Goodwin Avenue; Urbana; IL; 61801; USA
2. Carrington Research Extension Center; North Dakota State University; 663 Hwy 281 N. PO Box 219; Carrington; ND; 58421; USA
3. Central Agricultural Research Center; Montana State University; 52583 US Hwy 87; Moccasin; MT; 59462; USA
4. Odum School of Ecology; The University of Georgia; Athens; GA; 30602; USA
5. Agricultural Research Center; Kansas State University; Hays; KS; 67601; USA
6. Department of Plant and Soil Sciences; Oklahoma State University; 368 Agricultural Hall; Stillwater; OK; 74078; USA
7. Division of Plant Sciences; University of Missouri; 1-31 Agriculture Building; Columbia; MO; 65211; USA