Spiralizations and tropisms in Arabidopsis roots

Trends Plant Sci. 2001 Dec;6(12):561-5. doi: 10.1016/s1360-1385(01)02152-5.


When Arabidopsis seedlings are grown on a hard-agar plate, their primary roots show characteristic spiralling movements, apparent as waves, coils and torsions, together with a slanting toward the right-hand side. All these movements are believed to be the result of three different processes acting on the roots: circumnutation, positive gravitropism and negative thigmotropism. The basic movement of the roots is described as that of a growing right-handed helix, which, because of the root tip hitting the agar plate, is continuously switched from the right-hand to the left-hand of the growth direction, and vice versa. This movement also produces a slanting root-growth direction toward the right-hand because of the incomplete waves made by the right-handed root to the left-hand. By contrast, the torsions seen in the coils and waves are interpreted as artefacts that form as an adaptation of the three-dimensional root helix to the flat two-dimensional agar surface.

Publication types

  • Review

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / growth & development*
  • Movement / physiology*
  • Plant Roots / genetics
  • Plant Roots / growth & development*
  • Tropism / physiology*