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A critical update on seed dormancy. I. Primary dormancy1

Published online by Cambridge University Press:  19 September 2008

Henk W. M. Hilhorst
Henk W. M. Hilhorst*
Affiliation:
Dept. of Plant Physiology, Wageningen Agricultural University, Arboretumlaan 4, NL-6703 BD Wageningen, Netherlands
*
*Correspondence
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Abstract

The emphasis of modern dormancy research is almost entirely on the form of dormancy that is acquired during seed development, primary dormancy. Abscisic acid (ABA) appears to be intimately involved in its regulation. The action of abscisic acid has also been implied in many other developmental processes. The coincidence of developmental events, such as dehydration and completion of maturation, with the acquisition of primary dormancy suggests that dormancy is influenced by these processes. Germinability, both during development and after maturation, is sometimes directly correlated with ABA content. The lack of such a correlation may be explained by assuming a decisive role for the responsiveness to ABA or other overriding factors. ABA has been detected in all seed components. The different seed tissues may all contribute, to various extents, to the degree of whole seed dormancy. It is concluded that ABA action in dormancy regulation is not restricted to the embryo but is also located in endospermic tissue. In addition, a role of ABA in the morphological development of germination modifying seed tissues is proposed. The mechanism for ABA action appears to be associated with cell wall properties.

Keywords

abscisic aciddormancygerminationprecocious germinationseedseed development
Type
Review Article
Information
Seed Science Research , Volume 5 , Issue 2 , June 1995 , pp. 61 - 73
Copyright
Copyright © Cambridge University Press 1995

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Footnotes

1

An update on secondary dormancy will be published in a later issue of the journal

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