Hydrotropism and its interaction with gravitropism in roots

Hideyuki Takahashi

Research output: Contribution to journalArticlepeer-review

24 Citations (Scopus)


We have studied hydrotropism and its interaction with gravitropism in agravitropic roots of a pea mutant and normal roots of peas (Pisum sativum L.) and maize (Zea mays L.). The interaction between hydrotropism and gravitropism in normal roots of peas or maize were also examined by nullifying the gravitropic response on a clinostat and by changing the stimulus-angle for gravistimulation. Depending on the intensity of both hydrostimulation and gravistimulation, hydrotropism and gravitropism of seedling roots strongly interact with one another. When the gravitropic response was reduced, either genetically or physiologically, the hydrotropic response of roots became more unequivocal. Also, roots more sensitive to gravity appear to require a greater moisture gradient for the induction of hydrotropism. Positive hydrotropism of roots occurred due to a differential growth in the elongation zone; the elongation was much more inhibited on the moistened side than on the dry side of the roots. It was suggested that the site of sensory perception for hydrotropism resides in the root cap, as does the sensory site for gravitropism. Furthermore, an auxin inhibitor, 2,3,5-triiodobenzoic acid (TIBA), and a calcium chelator, ethyleneglycol-bis-(β-aminoethylether)-N,N,N′,N′- tetraacetic acid (EGTA), inhibited both hydrotropism and gravitropism in roots. These results suggest that the two tropisms share a common mechanism in the signal transduction step.

Original languageEnglish
Pages (from-to)301-308
Number of pages8
JournalPlant and Soil
Issue number2
Publication statusPublished - 1994 Jun 1


  • gravitropism
  • hydrotropism
  • maize (Zea mays L.)
  • mutant
  • pea (Pisum sativum L.)
  • root

ASJC Scopus subject areas

  • Soil Science
  • Plant Science


Dive into the research topics of 'Hydrotropism and its interaction with gravitropism in roots'. Together they form a unique fingerprint.

Cite this