Effects of gibberellic acid and zeatin on the growth response of cucumber cotyledons

Robert M. Muir, Yeong Jing Cheng

Research output: Contribution to journalArticle

2 Citations (Scopus)


In contrast to cytokinin, gibberellic acid has no effect on the growth of the isolated cucumber cotyledon in darkness. Like cytokinins in light, gibberellic acid causes increases in fresh weight and area of the cotyledon at concentrations from 10-7 to 10-3 M. Radiant energies in the blue, red, and far-red regions of the spectrum all induce the growth responses to gibberellic acid. The effect of the far red is greater than that of the red, which is greater than that of the blue. Gibberellic acid is ineffective in the promotion of chlorophyll development, whereas cytokinins are very effective. Although zeatin and gibberellic acid both cause an increase in fresh weight and area of the cotyledons in light, they appear to have entirely separate actions in the growth responses.

Original languageEnglish
Pages (from-to)197-201
Number of pages5
JournalJournal of Plant Growth Regulation
Issue number4
Publication statusPublished - 1988 Dec 1


ASJC Scopus subject areas

  • Agronomy and Crop Science
  • Plant Science

Cite this