1. Department of Plant Nutrition; College of Resources and Environmental Science; China Agricultural University; Beijing 100193 China
2. Crop Functional Genomics; Institute of Crop Science and Resource Conservation (INRES); University of Bonn; Bonn 53113 Germany
3. State Key Laboratory of Plant Genomics; Institute of Genetics and Developmental Biology; Chinese Academy of Sciences; Beijing 100101 China
4. Faculty of Biology, Genetics; LMU Munich; Martinsried 82152 Germany
5. Plant Genetics; School of Life Science Weihenstephan; Technical University of Munich (TUM); Freising 85354 Germany