Abstract

Initiation of dormancy in woody species is induced by a short photoperiod. In the early stages of dormancy development, growth can be initiated by long days. To study the possible involvement of gibberellins and indole-3-acetic acid in bud break in Salix pentandra, effects on levels of these plant hormones of transfer of seedlings in an early stage of dormancy to a growth-inductive long photoperiod was investigated. The bud break and initiation of growth correlated with a rapid transient increase in GA, in defined zones of shoot tips to levels twice of that in continuously elongating long day-grown control seedlings, followed by a rapid decrease to levels similar to in these control plants. Also, the contents of GA(53), GA(19), GA(201) GA(8) increased upon transfer from short to long days. Levels of indole-3-acetic acid showed a gradual decline under short days, and increased gradually upon transfer to long days up to a level of continuously elongating plants. The present data suggest an interaction between gibberellin and indole-3-acetic acid in the photoperiodic control of dormancy development and bud break in S. pentandra.

Keywords

bud break; gibberellins; IAA; indole-3-acetic acid; photoperiod; Salix pentandra

Published in

Plant and Cell Physiology
1997, Volume: 38, number: 5, pages: 536-540
Publisher: OXFORD UNIV PRESS

SLU Authors

• Moritz, Thomas

  • Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Botany


Publication identifier

DOI: https://doi.org/10.1093/oxfordjournals.pcp.a029202

Permanent link to this page (URI)

https://res.slu.se/id/publ/42931