1. Donald Danforth Plant Science Center, St. Louis, Missouri 63132;
2. Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, United Kingdom;
3. Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588;
4. National Root Crops Research Institute, Umudike, Nigeria;
5. Department of Horticulture, Washington State University, Pullman, Washington 99164-6340;
6. Swiss Federal Institute of Technology, ETH Zürich, Zürich 8092, Switzerland;
7. Kenyan Agricultural Research Institute, Nairobi, Kenya;
8. International Institute for Tropical Agriculture, Ibadan, Nigeria;
9. Department of Biology, University of Puerto Rico, Mayaguez 00681, Puerto Rico;
10. Institute of Plant Physiology & Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200032 Shanghai, China