1. Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin 53706
2. Laboratory of Molecular and Cellular Biology, University of Wisconsin-Madison, Madison, Wisconsin 53706
3. Center for Applied Plant Sciences, Department of Molecular Genetics and Department of Horticulture and Crop Science, The Ohio State University, Columbus, Ohio 43210
4. Laboratory for Optical and Computational Instrumentation, University of Wisconsin-Madison, Madison, Wisconsin 53706
5. Department of Biological Sciences, University of Tokyo, Hongo, Bunkyo-ku Tokyo 113-0033, Japan
6. Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin 53706