Journal Article

Post-abscission, pre-dispersal seeds of <i>Digitalis purpurea</i> remain in a developmental state that is not terminated by desiccation <i>ex planta</i>

L. H. Butler, F. R. Hay, R. H. Ellis and R. D. Smith

in Annals of Botany

Published on behalf of The Annals of Botany Company

Volume 103, issue 5, pages 785-794
Published in print March 2009 | ISSN: 0305-7364
Published online January 2009 | e-ISSN: 1095-8290 | DOI: http://dx.doi.org/10.1093/aob/mcn254
Post-abscission, pre-dispersal seeds of Digitalis purpurea remain in a developmental state that is not terminated by desiccation ex planta

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

Seed quality may be compromised if seeds are harvested before natural dispersal (shedding). It has been shown previously that slow or delayed drying can increase potential quality compared with immediate rapid drying. This study set out to investigate whether or not there is a critical moisture content, below which drying terminates maturation events for seeds harvested after mass maturity but before dispersal.

Methods

Seeds of foxglove (Digitalis purpurea) in the post-abscission pre-dispersal phase were held at between 15 and 95 % RH for 4 or 8 d, with or without re-hydration to 95 % RH for a further 4 d, before drying to equilibrium at 15 % RH. In addition, dry seeds were primed for 48 h at −1 MPa. Subsequent seed longevity was assessed at 60 % RH and 45 °C.

Key Results

Rate of germination and longevity were improved by holding seeds at a wide range of humidities after harvest. Longevity was further improved by re-hydration at 95 % RH. Priming improved the longevity of the seeds dried immediately after harvest, but not of those first held at 95 % RH for 8 d prior to drying.

Conclusions

Maturation continued ex planta in these post-abscission, pre-dispersal seeds of D. purpurea dried at 15–80 % RH at a rate correlated positively with RH (cf. ageing of mature seeds). Subsequent re-hydration at 95 % RH enabled a further improvement in quality. Priming seeds initially stored air-dry for 3 months also allowed maturation events to resume. However, once individual seeds within the population had reached maximum longevity, priming had a negative impact on their subsequent survival.

Keywords: Digitalis purpurea; seed development; post-harvest treatment; priming; longevity; ex situ conservation

Journal Article.  7458 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.