Hostname: page-component-848d4c4894-2xdlg Total loading time: 0 Render date: 2024-07-07T04:22:36.208Z Has data issue: false hasContentIssue false

Induced dormancy and colour polymorphism in seeds of the bull thistle Cirsium vulgare (Savi) Ten.

Published online by Cambridge University Press:  19 September 2008

Colleen Doucet*
Affiliation:
Department of Plant Sciences, University of Western Ontario, London, Ontario, N6A 5B7, Canada
Paul B. Cavers
Affiliation:
Department of Plant Sciences, University of Western Ontario, London, Ontario, N6A 5B7, Canada
*
*correspondence

Abstract

To colonize newly disturbed areas, weedy species must disperse their seeds in space and/or in time. Cirsium vulgare has poor dispersal in space, but can form a persistent seed bank. Fresh seeds are capable of germinating in either light/dark or constant dark conditions under favourable diurnal temperatures of 25°C: 10°C. Despite this lack of dormancy, a large proportion of seeds do not germinate in the autumn after dispersal. Variation in germination requirements according to seed colour was also examined. Fresh seeds were placed under one of two overwintering treatments at 5°C, alternating light/dark or constant darkness. Some seeds of all colours: white, light, intermediate, dark and black germinated under these conditions. Six months later, ungerminated seeds subjected to the light/dark treatment did not require light for germination when placed under optimal temperatures. However, most seeds that had overwintered in constant darkness required light for germination. In the field, this induced dormancy would prevent seeds from germinating if buried or located in deep shade. Such seeds have the potential of forming a persistent seed bank. The proportion of dormant seeds did not appear to be associated with seed colour. Seeds incubated at 10°C following overwintering under light/dark conditions germinated to a higher percentage than seeds overwintered in darkness, regardless of the light conditions for germination. The results of this study help to explain the contradiction between delayed germination in the field and the lack of seed dormancy.

Type
Ecology
Copyright
Copyright © Cambridge University Press 1997

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

Alex, J.F. and Switzer, C.M. (1976) Ontario Weeds, Publication 505, Ontario Ministry of Agriculture and Food.Google Scholar
Andersson, S. (1996) Seed size as a determinant of germination rate in Crepis tectorum (Asteraceae): evidence from a seed burial experiment. Canadian Jounal of Botany 74, 568572.CrossRefGoogle Scholar
Baskin, J.M. and Baskin, C.C. (1985) The annual dormancy cycle in buried weed seeds: a continuum. BioScience 35, 492498.CrossRefGoogle Scholar
Bewley, J.D. and Black, M. (1994) Seeds. Physiology of development and germination (2nd edition). New York, Plenum Press.CrossRefGoogle Scholar
Breeman, A.M.M. van and Leeuwen, B.H. van (1983) The seed bank of three short-lived monocarpic species, Cirsium vulgare (Compositae), Echium vulgare and Cynoglossum officinale (Boraginaceae). Acta Botanica Neerlandica 32, 245246.Google Scholar
Brown, A.L. (1978) Ecology of soil organisms. London, Heinemann Educational Books.Google Scholar
Cavers, P.B. and Harper, J.L. (1966) Germination polymorphism in Rumex crispus and Rumex obtusifolius. Journal of Ecology 54, 367382.CrossRefGoogle Scholar
Doucet, C. (1995) Phénoplasticité des akènes chez Aster umbellatus. MSc Thesis, Université de Moncton, Moncton, Canada.Google Scholar
Doucet, C. (1996) Seed colour variation, dormancy, and seed banks in the bull thistle, Cirsium vulgare (Savi) Ten. PhD Thesis, University of Western Ontario, London, Canada.Google Scholar
Doucet, C. and Cavers, P.B. (1996) A persistent seed bank of the bull thistle Cirsium vulgare (Savi) Ten. Canadian Journal of Botany 74, 13861391.CrossRefGoogle Scholar
Enright, N.J. and Cameron, E.K. (1988) The soil seed bank of a kauri (Agathis australis) forest remnant near Auckland, New Zealand. New Zealand Journal of Botany 26, 223236.CrossRefGoogle Scholar
Fenner, M. (1980) The induction of a light requirement in Bidens pilosa seeds by leaf canopy shade. New Phytologist 84, 103106.CrossRefGoogle Scholar
Grant Lipp, A.E. and Ballard, L.A.T. (1963) Germination patterns shown by the light-sensitive seed of Anagallis arvensis. Australian Journal of Biological Sciences 16, 572584.CrossRefGoogle Scholar
Gutterman, Y. (1980/1981) Influences on seed germinability: phenotypic maternal effects during seed maturation. Israel Journal of Botany 29, 105117.Google Scholar
Harper, J.L. (1977) Population biology of plants. London, Academic Press.Google Scholar
Hilhorst, H.W.M. and Karssen, C.M. (1992) Seed dormancy and germination: the role of abscisic acid and gibberellins and the importance of hormone mutants. Plant Growth Regulation 11, 225238.CrossRefGoogle Scholar
Klinkhamer, P.G.L. and Jong, T.J. de (1989) Cirsium vulgare. CRC Handbook of Flowering 6, 228233.Google Scholar
Klinkhamer, P.G.L. and Jong, T.J. de (1993) Biological flora of the British Isles. Cirsium vulgare (Savi) Ten. (Carduus lanceolatus L., Cirsium lanceolatum (L.) Scop., non Hill). Journal of Ecology 81, 177191.CrossRefGoogle Scholar
Leeuwen, B.H. van and Breemen, A.M.M. van (1980) Similarities and differences in some biennials. Acta Botanica Neerlandica 29, 209210.Google Scholar
Lincoln, W.C.L. Jr. (1981) Laboratory germination of Cirsium vulgare — bull or spear thistle. Newsletter of the Association of Official Seed Analysts 55, 6769.Google Scholar
Matthews, D. (1963) Laboratory identification of seeds of some thistles. Cirsium arvense, Cirsium vulgare, Carduus nutans. Proceedings of the International Seed Testing Association 28, 1926.Google Scholar
Pons, T.L. (1984) Possible significance of changes in the light requirement of Cirsium palustre seeds after dispersal in ash coppice. Plant Cell and Environment 7, 263268.CrossRefGoogle Scholar
Pons, T.L. (1991) Induction of dark dormancy in seeds: its importance for the seed bank in the soil. Functional Ecology 5, 669675.CrossRefGoogle Scholar
Pons, T.L. (1992) Seed responses to light. pp. 259284in Fenner, M. (Ed) Seeds: the ecology of regeneration in plant communities, UK, CAB INTERNATIONAL.Google Scholar
Prinzie, T.P. and Chmielewski, J.G. (1994) Significance of achene characteristics and within-achene resource allocation in the germination strategy of tetraploid Aster pilosus var. pilosus (Asteraceae). American Journal of Botany 81, 259264.Google Scholar
Roberts, H.A. and Chancellor, R.J. (1979) Periodicity of seedling emergence and achene survival in some species of Carduus, Cirsium and Onopordum. Journal of Applied Ecology 16, 641647.CrossRefGoogle Scholar
Russell, E.W. (1973) Soil conditions and plant growth (10th edition). New York, Longman Inc.Google Scholar
Salisbury, E.J. (1964) Weeds and aliens (2nd edition). London, Collins.Google Scholar
Staden, J. van, Kelly, K.M. and Ross, J.A. (1995) Changes in germination requirements of Cirsium vulgare with storage. South African Journal of Botany 61, 14.CrossRefGoogle Scholar
Stevens, J. (1990) Intermediate statistics: a modern approach. Hillsdale, New Jersey, USA, L. Erlbaum Associates.Google Scholar
Thompson, K. and Grime, J.P. (1979) Seasonal variation in the seed banks of herbaceous species in ten contrasting habitats. Journal of Ecology 67, 893921.CrossRefGoogle Scholar
Threadgill, P.F. (1986) Variations in the biennial life history strategy among 15 ruderal species in an abandoned gravel pit near London, Ontario. PhD thesis, University of Western Ontario, London, Canada.Google Scholar
Turkington, R.A., Cavers, P.B. and Rempel, E. (1978) The biology of Canadian weeds. 29. Melilotus alba Desr. and Melilotus officinalis (L.) Lam. Canadian Journal of Plant Science 58, 523537.CrossRefGoogle Scholar
Wesson, G. and Wareing, P.F. (1969) The induction of light sensitivity in weed seeds by burial. Journal of Experimental Botany 20, 414425.CrossRefGoogle Scholar
Zar, J.H. (1984) Biostatistical analysis (2nd edition). Englewood Cliffs, New Jersey, USA, Prentice Hall Inc.Google Scholar