Abstract
When plant stems are mechanically perturbed by wind or rubbing, they respond thigmomorphogenetically by retarding their elongation and increasing their radial growth. The perception of the perturbation seems to be membrane related. A burst of ethylene production occurs 30 min after perturbation and peaks at about 90–180 min. This ethylene seems to be responsible for the subsequent biochemical, anatomical, and morphological changes associated with thigmomorphogenesis.