Melatonin acts as a growth-stimulating compound in some monocot species

J Pineal Res. 2005 Sep;39(2):137-42. doi: 10.1111/j.1600-079X.2005.00226.x.

Abstract

In a recent study melatonin (N-acetyl-5-methoxytryptamine), a well-investigated animal molecule but minimally studied in plants, was seen to have a physiological role as growth-promoting molecule in lupin hypocotyls. In the present study, the role of melatonin as a growth promoter is extended to coleoptiles of canary grass, wheat, barley and oat, in which it shows a relative auxinic activity [with respect to indole-3-acetic acid (IAA), the main auxin in plants] of between 10 and 55%. In addition, melatonin is seen to have an important inhibitory growth effect on roots similar to that played by auxin. The quantitation by liquid chromatography with electrochemical detection and identification by tandem mass spectrometry of melatonin and IAA in etiolated coleoptiles of the monocots assayed showed that both compounds are present in similar levels in these tissues. These results point to the co-existence of auxin and melatonin in tissues and raises the possibility of their co-participation in some physiological actions as auxinic hormones in plants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Avena / drug effects
  • Avena / growth & development
  • Avena / metabolism
  • Chromatography, High Pressure Liquid
  • Growth Substances / pharmacology*
  • Hordeum / drug effects
  • Hordeum / growth & development
  • Hordeum / metabolism
  • Indoleacetic Acids / metabolism
  • Indoleacetic Acids / pharmacology
  • Melatonin / pharmacology*
  • Phalaris / drug effects
  • Phalaris / growth & development
  • Phalaris / metabolism
  • Plant Roots / drug effects
  • Plant Roots / growth & development
  • Plant Roots / metabolism
  • Plant Stems / drug effects
  • Plant Stems / growth & development
  • Plant Stems / metabolism
  • Poaceae / drug effects*
  • Poaceae / growth & development*
  • Poaceae / metabolism
  • Spectrometry, Mass, Electrospray Ionization
  • Triticum / drug effects
  • Triticum / growth & development
  • Triticum / metabolism

Substances

  • Growth Substances
  • Indoleacetic Acids
  • indoleacetic acid
  • Melatonin