Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-28T06:18:10.972Z Has data issue: false hasContentIssue false

Combinational dormancy in winter annual Fabaceae

Published online by Cambridge University Press:  30 July 2010

Jozef A. Van Assche*
Affiliation:
Laboratory of Plant Ecology, Catholic University Leuven, Kasteelpark Arenberg 31, B-3001 Leuven, Belgium
Filip E.A. Vandelook
Affiliation:
Laboratory of Plant Ecology, Catholic University Leuven, Kasteelpark Arenberg 31, B-3001 Leuven, Belgium
*
*Correspondence Fax: +3216321968 Email: [email protected]

Abstract

Among 14 species of herbaceous Fabaceae, all six winter annuals show a marked non-deep physiological dormancy of the embryo in addition to physical dormancy. This physiological dormancy is apparent at 23°C, but not at lower temperatures of 10°C and 5°C and disappears after 3 months of dry storage. These results corroborate the hypothesis that combinational dormancy is a double safety mechanism for delaying germination during summer: physical dormancy postpones germination, and even in early softened seeds germination is prevented by physiological dormancy of the embryo. Softened, swollen seeds of Medicago arabica tolerate a subsequent desiccation and remain viable even after five cycles of dehydration and rehydration. The rate of natural softening of M. arabica seeds increases exponentially at higher temperatures, with a Q10 between 3.4 and 5.1, and obeys the Arrhenius equation. This indicates that a chemical reaction might be involved in breakdown of physical dormancy. Winter annuals with hard seeds show similar properties as winter annuals with permeable seeds: the need for afterripening and requirement of lower temperatures delay germination until autumn. Only one species, Vicia sativa, loses physical dormancy during dry storage. Drying during summer might be a supplementary cue for germination in autumn.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2010

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

Ballard, L.A.T. (1958) Studies of dormancy in the seeds of subterranean clover (Trifolium subterraneum L.). 1. Breaking of dormancy by carbon dioxide and by activated carbon. Australian Journal of Biological Sciences 11, 246260.CrossRefGoogle Scholar
Baskin, C.C. (2003) Breaking physical dormancy in seeds – focussing on the lens. New Phytologist 158, 229232.CrossRefGoogle Scholar
Baskin, C.C. and Baskin, J.M. (1998) Seeds. Ecology, biogeography and evolution of dormancy and germination. San Diego, Academic Press.Google Scholar
Baskin, J.M. and Baskin, C.C. (1974) Some eco-physiological aspects of seed dormancy in Geranium carolinianum L. from Central Tennessee. Oecologia 16, 209219.CrossRefGoogle ScholarPubMed
Baskin, J.M. and Baskin, C.C. (2004) A classification system for seed dormancy. Seed Science Research 14, 116.CrossRefGoogle Scholar
Baskin, J.M., Baskin, C.C. and Li, X.J. (2000) Taxonomy, anatomy and evolution of physical dormancy in seeds. Plant Species Biology 15, 139152.CrossRefGoogle Scholar
Berrie, A.M.M. and Drennan, D.S.H. (1971) The effect of hydration–dehydration on seed germination. New Phytologist 70, 135142.CrossRefGoogle Scholar
Berry, J.A. and Raison, J.K. (1981) Responses of macrophytes to temperature. pp. 277338in Lange, O.L.; Nobel, P.S.; Osmond, C.B.; Ziegler, H. (Eds) Physiological plant ecology, Vol. 12A. Berlin, Springer-Verlag.Google Scholar
Bewley, J.D. and Black, M. (1994) Seeds, physiology of development and germination (2nd edition). New York, Plenum Press.CrossRefGoogle Scholar
Borris, H. (1940) Über die inneren Vorgänge bei der Samenkeimung und ihre Beeinflussung durch Aussenfaktoren. Jahrbuch für Wissenschaftliche Botanik 89, 254339.Google Scholar
Geneve, R.L. (1991) Seed dormancy in eastern redbud (Cercis canadensis). Journal of American Society of Horticultural Science 116, 8588.CrossRefGoogle Scholar
Grant Lipp, A.E. and Ballard, L.A.T. (1959) The breaking of seed dormancy of some legumes by carbon dioxide. Australian Journal of Agricultural Research 10, 495499.CrossRefGoogle Scholar
Grime, J.P., Mason, G., Curtis, A.V., Rodman, J., Band, S.R., Mowforth, M.A.G., Neal, A.M. and Shaw, S. (1981) A comparative study of germination characteristics in a local flora. Journal of Ecology 69, 10171059.CrossRefGoogle Scholar
Hegarty, T.W. (1978) The physiology of seed hydration and dehydration, and the relation between water stress and the control of germination: a review. Plant Cell and Environment 1, 101119.CrossRefGoogle Scholar
Jansen, P.I. and Ison, R.L. (1994) Hydration–dehydration and subsequent storage effects on seed of the self-regenerating annuals Trifolium balansae and T. resupinatum. Seed Science and Technology 22, 435447.Google Scholar
Katznelson, J. and Carpenter, J.A. (1972) Germination of subterranean clover in a Mediterranean summer. Israel Journal of Botany 21, 228242.Google Scholar
Kigel, J. (1995) Seed germination in arid and semi-arid regions. pp. 645700in Kigel, J.; Galili, G. (Eds) Seed development and germination. New York, Marcel Dekker.Google Scholar
McKersie, B.D. and Stinson, R.H. (1980) Effect of dehydration on leakage and membrane structure in Lotus corniculatus L. seeds. Plant Physiology 66, 316320.CrossRefGoogle ScholarPubMed
Meulebrouck, K., Ameloot, E., Van Assche, J.A., Verheyen, K., Hermy, M. and Baskin, C.C. (2008) Germination ecology of the holoparasite Cuscuta epithymum. Seed Science Research 18, 2534.CrossRefGoogle Scholar
Morrison, D.A., Auld, T.D., Rish, S., Porter, C. and McClay, K. (1992) Patterns of testa-imposed seed dormancy in native Australian legumes. Annals of Botany 70, 157163.CrossRefGoogle Scholar
Norman, H.C., Cocks, P.S., Smith, F.P. and Nutt, B.J. (1998) Reproductive strategies in Mediterranean annual clovers: germination and hardseededness. Australian Journal of Agricultural Research 49, 973982.CrossRefGoogle Scholar
Profumo, P. and Gastaldo, P. (1977) Ulteriori richerche sulla germinazione di Cercis siliquastrum L. Azione dell'acido gibberellico e ruolo dell'endosperma nel fenomeno della dormienza. Giornale Botanico Italiano 111, 211218.CrossRefGoogle Scholar
Taylor, G.B. (1981) Effect of constant temperature treatments followed by fluctuating temperatures on the softening of hard seeds of Trifolium subterraneum L. Australian Journal of Plant Physiology 8, 547558.Google Scholar
Thomson, J.R. (1965) Breaking dormancy in germination tests of Trifolium spp. Proceedings of the International Seed Testing Association 30, 905909.Google Scholar
Van Assche, J.A. and Vandelook, F.E.A. (2006) Germination ecology of eleven species of Geraniaceae and Malvaceae, with special reference to the effects of drying seeds. Seed Science Research 16, 283290.CrossRefGoogle Scholar
Van Assche, J.A., Debucquoy, K.L.A. and Rommens, W.A.F. (2003) Seasonal cycles in the germination capacity of buried seeds of some Leguminosae (Fabaceae). New Phytologist 158, 315323.CrossRefGoogle Scholar