Retraction to: Plant Cell Rep (2011) 30:1603–1616 DOI 10.1007/s00299-011-1071-5

This article has been retracted on the demand of the authors because of error in one figure panel. Consequently, the data is not unambiguous. All of the authors have agreed with the retraction notice and sincerely regret the inconvenience that this retraction causes to PCR and its readership.