Journal Article

Prior hydration of <i>Brassica tournefortii</i> seeds reduces the stimulatory effect of karrikinolide on germination and increases seed sensitivity to abscisic acid

Rowena L. Long, Kimberlyn Williams, Erin M. Griffiths, Gavin R. Flematti, David J. Merritt, Jason C. Stevens, Shane R. Turner, Stephen B. Powles and Kingsley W. Dixon

in Annals of Botany

Published on behalf of The Annals of Botany Company

Volume 105, issue 6, pages 1063-1070
Published in print June 2010 | ISSN: 0305-7364
Published online March 2010 | e-ISSN: 1095-8290 | DOI: http://dx.doi.org/10.1093/aob/mcq061
Prior hydration of Brassica tournefortii seeds reduces the stimulatory effect of karrikinolide on germination and increases seed sensitivity to abscisic acid

More Like This

Show all results sharing these subjects:

  • Ecology and Conservation
  • Evolutionary Biology
  • Plant Sciences and Forestry

GO

Show Summary Details

Preview

Background and Aims

The smoke-derived compound karrikinolide (KAR1) shows significant potential as a trigger for the synchronous germination of seeds in a variety of plant-management contexts, from weed seeds in paddocks, to native seeds when restoring degraded lands. Understanding how KAR1 interacts with seed physiology is a necessary precursor to the development of the compound as an efficient and effective management tool. This study tested the ability of KAR1 to stimulate germination of seeds of the global agronomic weed Brassica tournefortii, at different hydration states, to gain insight into how the timing of KAR1 applications in the field should be managed relative to rain events.

Methods

Seeds of B. tournefortii were brought to five different hydration states [equilibrated at 15 % relative humidity (RH), 47 % RH, 96 % RH, fully imbibed, or re-dried to 15 % RH following maximum imbibition] then exposed to 1 nm or 1 µm KAR1 for one of five durations (3 min, 1 h, 24 h, 14 d or no exposure).

Key Results

Dry seeds with no history of imbibition were the most sensitive to KAR1; sensitivity was lower in seeds that were fully imbibed or fully imbibed then re-dried. In addition, reduced sensitivity to KAR1 was associated with an increased sensitivity to exogenously applied abscisic acid (ABA).

Conclusions

Seed water content and history of imbibition were found to significantly influence whether seeds germinate in response to KAR1. To optimize the germination response of seeds, KAR1 should be applied to dry seeds, when sensitivity to ABA is minimized.

Keywords: Karrikinolide; karrikins; butenolide; smoke; germination stimulant; seed water content; abscisic acid; ABA; gibberellin; weed; Brassica tournefortii

Journal Article.  5288 words.  Illustrated.

Subjects: Ecology and Conservation ; Evolutionary Biology ; Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.