Journal Article

Gravitropism of Oat and Wheat Coleoptiles: Dependence on the Stimulation Angle and Involvement of Autotropic Straightening

Yutaka Tarui and Moritoshi Iino

in Plant and Cell Physiology

Published on behalf of Japanese Society of Plant Physiologists

Volume 38, issue 12, pages 1346-1353
Published in print January 1997 | ISSN: 0032-0781
Published online January 1997 | e-ISSN: 1471-9053 | DOI: https://dx.doi.org/10.1093/oxfordjournals.pcp.a029128
Gravitropism of Oat and Wheat Coleoptiles: Dependence on the Stimulation Angle and Involvement of Autotropic Straightening

More Like This

Show all results sharing these subjects:

  • Biochemistry
  • Molecular and Cell Biology
  • Plant Sciences and Forestry

GO

Show Summary Details

Preview

Gravitropism of oat (Avena sativa L.) and wheat (Triti-cum aestivum L.) coleoptiles was investigated in relation to the displacement angle or to the initially set stimulation angle (SA). We measured curvature rates at the early phase of curvature, before it was affected by the drop in SA resulting from the curvature response itself. The plot of the rates against the sines of initial SAs revealed similar curves for oats and wheat, which approached saturation as the sine increased to unity. The two species and previously analyzed rice [lino et al. (1996) Plant Cell Environ. 19: 1160] appeared to have similar gravisensitivities. Initial SAs below and over 90° yielded comparable rates when the sine values were the same, indicating that the extent of gravitropism is determined by the gravity component perpendicular to the organ's long axis. Long-term curvature kinetics at different SAs indicated that the net curvature rate dropped sharply before the tip reached the vertical position and then the tip approached the vertical slowly, with clear oscillatory movements in the case of wheat. During this late curvature phase, the coleoptile straightened gradually, although none of its parts had yet reached the vertical. When rotated on horizontal clinostats or displaced upwards to reduce SA in the late curvature phase, coleoptiles bent in the opposite direction. These results demonstrated that autotropism counteracts gravitropism to straighten coleoptiles.

Keywords: Autotropism; Coleoptile; Gravitropism; Oat (Avena sativa L.); Stimulation angle; Wheat (Triti-cum aestivum L.)

Journal Article.  0 words. 

Subjects: Biochemistry ; Molecular and Cell Biology ; Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.