1. Genome Center and Section of Plant Biology, University of California, Davis, California 95616 (D.B.-W., C.J., B.D., L.C.); Department of Horticulture and Landscape Architecture, Purdue University, Lafayette, Indiana 47907 (B.D.); Department of Biology, University of Washington, Seattle, Washington 98195 (N.K.); Department of Genetics, University of Potsdam, 14476 Potsdam-Golm, Germany (O.T., R.M.