1. Department of Plant Breeding, 240 Emerson Hall, Cornell University, Ithaca, NY 14853, USA
2. Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
3. Department of Plant Biology, Carnegie Institution of Washington, 260 Panama Street, Stanford, CA 94305, USA
4. Department of Biology, University of Missouri at St. Louis, St. Louis, MO 63121, USA
5. Maize Genetics Cooperation, Stock Center, Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA
6. Agricultural Research Service, United States Department of Agriculture, Soil and Nutrition Laboratory Research Unit, Cornell University, Ithaca, NY 14853, USA
7. Curtis Hall, University of Missouri at Columbia, Columbia, MO 65211, USA
8. Missouri Botanical Garden, 4344-Shaw Boulevard, St. Louis, MO 63110, USA