Ackno wledgem ents
The authors wish to apologize to all those ethylene scientists
whose work has not been mentioned due to space limitations.
We thank the Editor and two Reviewers for valuable comments
that led to the improvement of this review. This work was
supported by the Direccio´n General de Investigacio´n (Spain;
grant no. CGL2004-01996/BOS). M.A.M.V. is the recipient of
a doctoral fellowship from Ministerio de Educacio´n y Ciencia
(Spain) in the CSIC (EEZ, Granada, Spain). The English
version was prepared by D. Nesbitt.