Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-29T00:05:35.272Z Has data issue: false hasContentIssue false
  • English
  • Français

Seed development in Phaseolus vulgaris L. cv. Seminole. 3. NMR imaging of embryos during ethylene-induced precocious germination

Published online by Cambridge University Press:  19 September 2008

David W. Fountain ,
Lucy C. Forde ,
Edwin E. Smith ,
Karen R. Owens ,
Donald G. Bailey  and
Paul T. Callaghan
David W. Fountain*
Affiliation:
Department of Plant Biology and Biotechnology, Massey University, Palmerston North, New Zealand
Lucy C. Forde
Affiliation:
Department of Physics, Massey University, Palmerston North, New Zealand
Edwin E. Smith
Affiliation:
Department of Plant Biology and Biotechnology, Massey University, Palmerston North, New Zealand
Karen R. Owens
Affiliation:
Department of Physics, Massey University, Palmerston North, New Zealand
Donald G. Bailey
Affiliation:
Department of Physics, Massey University, Palmerston North, New Zealand
Paul T. Callaghan
Affiliation:
Department of Physics, Massey University, Palmerston North, New Zealand
*
*: Fax: 64 06 3505694 E-mail [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Embryos taken from late maturation phase seeds of Phaseolus vulgaris cv. Seminole prior to seed desiccation (35–45 DAA) can be induced to germinate in the absence of water by exogenous ethylene. NMR imaging of proton relaxation within the embryo shows changes in water status in putative (and not fully differentiated) vascular tissues of the hypocotyl within 3 h of ethylene administration. Difference imaging revealed that the change was progressive in the hypocotyl towards the radicle tip and was accompanied by changes in water status in the cotyledons. Water within plumular leaves was also affected. Increase in diameter of the hypocotyl–radicle axis (as estimated by pixel counts) was detectable from 3 h. Longitudinal radicle growth was detectable by NMR imaging at 18 h. Visible germination under the conditions used was apparent after 20 h. Changes in water status detected by this technique are an indication of changes in activity (concentration) or motion of water molecules or both. The data are consistent with a mode of action of ethylene in stimulating a redistribution of water within embryo structures from cotyledons to axis via the cotyledonary node and allowing the axis access to water sufficient to support germination. This supports the hypothesis that in vivo, quiescence at this developmental stage is induced and maintained by sequestration of water within the cotyledons.

Keywords

ethylenenuclear magnetic resonance imagingPhaseolusprecocious germinationwater imagingwater redistribution
Type
Physiology & Biochemistry
Information
Seed Science Research , Volume 8 , Issue 3 , September 1998 , pp. 357 - 365
Copyright
Copyright © Cambridge University Press 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abeles, F.B., Morgan, P.W. and Saltveit, M.E. (1992) Ethylene in plant biology, 2nd Ed, New York, Academic Press.Google Scholar
Bewley, J.D. and Black, M. (1982) Physiology and biochemistry of seeds in relation to germination, Vol 2. pp 231–233. Berlin, Springer-Verlag.CrossRefGoogle Scholar
Callaghan, P.T. (1991) Principles of NMR microscopy. Oxford, Oxford University Press.Google Scholar
Callaghan, P.T. (1992) Nuclear magnetic resonance microscopy. Proceedings of the Royal Microscopical Society 27, 67–70.Google Scholar
Ecker, J.R. (1995) The ethylene signal transduction pathway in plants. Science 268, 667–675.CrossRefGoogle ScholarPubMed
Fountain, D.W. and Outred, H.A. (1990) Seed development in Phaseolus vulgaris L. cv Seminole. II. Precocious germination in late maturation. Plant Physiology 93, 1089–1093.CrossRefGoogle ScholarPubMed
Mattysek, R., Tang, A.-C. and Boyer, J.S. (1991a) Plants can grow on internal water. Plant, Cell and Environment 14, 925–930.CrossRefGoogle Scholar
Mattysek, R., Murayama, S. and Boyer, J.S. (1991b) Growth-induced water potentials may mobilise internal water for growth. Plant, Cell and Environment 14, 917–923.CrossRefGoogle Scholar
Maurel, C., Reizer, J., Schroeder, J.I. and Chrispeels, M.J. (1993) The vacuolar membrane protein -TIP creates water specific channels in Xenopus oocytes. EMBO Journal 12, 2241–2247.CrossRefGoogle ScholarPubMed
Opik, H. (1965) Respiration rate, mitochondrial activity and mitochondrial structure in the cotyledons of Phaseolus vulgaris L. during germination. Journal of Experimental Botany 16, 667–682.CrossRefGoogle Scholar
Yeung, E.C. and Brown, D.C.W. (1982) The osmotic environment of developing embryos of Phaseolus vulgaris. Zeitschrift für Pflanzenphysiologie 106, 149–156.CrossRefGoogle Scholar
Yoshiyama, M., Yajima, H., Atsumi, T. and Esashi, Y. (1996) Mechanism of action of C2H4 in promoting the germination of cocklebur seeds. II. The role of C2H4 in the enhancement of priming effects. Australian Journal of Plant Physiology 23, 133–139.Google Scholar