Effect of Mechanical Stimulation on the Electrical and Curvature Responses in the Avena Coleoptile

Some Effects of Decapitation on Electrical and Elongation Phenomena in the Avena Coleoptile

“…This mechanically stimulated region immediately became more negative with respect to the basal and grounded contact region. Such increase in negativity of the stimulated region is in agreement with results from the onion root (6), from Chara (1), and from Avena (7). Because of the orientation of the inherent electrical polarity, this stimulation resulted in a rapid increase in the potential difference.…”

“…Previous investigations have demonstrated that the electrical pattern of Avena is sensitive to mechanical stimulation (7). The data in figure 3 show that the initial electrical response caused by manual decapitation can be substantially reduced by use of a mechanical decapitator.…”

Plant Tropisms

“…had been removed for 130 min., gave no growth curvature (39). Such stimulation, however, causes the seedling to establish a transverse electrical polarity, which is about the same as in intact plants.…”

“…did not increase the geotropic curvature, but neither did it inhibit such bending. Later experiments (39), -in which an electrical vibrator was used for mechanical stimulation, demonstrated that the magnitude of the trans verse electrical polarity, its rate of change, and the rate of growth curvature are dependent on the duration of the mechanical stimulation. ( T he duration of stimulation is actually a measure of the number of weak taps that were applied.)…”

Inhibition of Curvature Responses by Shunting the Inherent Electrical Field

“…The techniques for making the electrical measurements have been published in preceding papers (3,4).…”