1. Australian Research Council Centre of Excellence for Integrative Legume Research, The University of Queensland, St Lucia, Brisbane, 4072 Australia (C.A.B.);
2. School of Plant Science, University of Tasmania, G.P.O. Box 252–55 Hobart, Tasmania 7001 Australia (J.L.W.);
3. Department of Biology, Carleton College, Northfield, Minnesota 55057 (S.R.S.); and
4. Department of Crop Genetics, John Innes Centre, Norwich NR4 7UH, United Kingdom (J.M.I.H.)