1. Leibniz Institute of Plant Genetics and Crop Plant Research, 06466 Gatersleben, Germany
2. Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan
3. Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Plant Molecular Biology, Ceske Budejovice 37005, Czech Republic
4. Departamento de Genética, Facultad de Biología, Universidad Complutense, 28040 Madrid, Spain