Thigmomorphogenesis: Changes in cell division and elongation in the internodes of mechanically-perturbed or ethrel-treated bean plants

Abstract

Examination of first internodes of young Phaseolus vulgaris L. plants which have been subjected to mechanical perturbation shows decreased elongation and increased radial growth. The decreased elongation can be attributed to both reduced cell elongation of epidermal and cortical cells and a reduced number of cells in the vascular and pith tissues. The increased radial enlargement is due to increased cortical cell expansion and increased secondary xylem production resulting from increased cambial activity. All of these responses are observable within a few hours of a single mechanical perturbation. Treatment of plants with ethrel mimics all of these effects of mechanical perturbation. © 1980 Annals of Botany Company.