1. The State Key Laboratory of Plant Cell and Chromosome Engineering; Center for Agricultural Research Resources; Institute of Genetics and Developmental Biology; Chinese Academy of Sciences; 286 Huaizhong Road Shijiazhuang Hebei 050021 China
2. University of Chinese Academy of Sciences; No.19A Yuquan Road Beijing 100049 China
3. Max-Planck Institute for Plant Breeding Research; Carl-von-Linné-Weg 10 Cologne D-50829 Germany
4. Institute of Plant Biology, Biological Research Center of Hungarian Academy of Sciences; Temesvári krt. 62 Szeged H-6726 Hungary