1. Max Planck Partner Group Departamento de Biologia Vegetal Universidade Federal de Viçosa 36570‐900 Viçosa Minas Gerais Brazil
2. Max‐Planck‐Institute of Molecular Plant Physiology Am Mühlenberg 1 14476 Potsdam‐Golm Germany
3. Department of Plant Biochemistry Heinrich Heine University Düsseldorf 40225 Düsseldorf Germany
4. Department of Plant Physiology University of Kaiserslautern D‐67663 Kaiserslautern Germany
5. Department of Biosciences, Biotechnology and Biopharmaceutics University of Bari 70125 Bari Italy