Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-10T23:23:20.121Z Has data issue: false hasContentIssue false

Physical dormancy in Geraniaceae seeds

Published online by Cambridge University Press:  22 February 2007

A. Meisert*
Affiliation:
Department of Biology, University of Hildesheim Marienburger Platz 22, Hildesheim 31141 Germany
*
*Correspondence Fax: +49–05121–883–177 Email: meisert@rz.uni-hildesheim.de

Abstract

Seed dormancy was analysed in Geraniaceae, testing 29,103 seeds of 35 species for seed-coat impermeability to water. Seeds of wild and cultivated species from a number of different climatic/ecological zones (northern Germany, the Canary Islands and South Africa) were investigated. Seeds from cultivated plants and natural populations had similar (±2%) percentages of water-impermeable seeds. The percentages of impermeable seeds at maturity were also mostly constant (±2%) for two different years. The species analysed contained from 0 to 100% impermeable seeds at maturity, and could be classified into three quantitative types of physical dormancy: four species with no impermeable seeds (PY0), 10 species with a maximum of 80% impermeable seeds (PY80), and 21 species with more than 80% impermeable seeds (PY100). Species with different life cycles and from very different habitats, e.g. Geranium pratense or Pelargonium capitatum, belonged to the PY100 group. However, all of the succulent shrubs investigated from the genus Pelargonium were PY0 species. Five years of dry storage at 20 ± 5°C decreased physical dormancy in a species-dependent fashion. Erodium cicutarium, for example, had 95% impermeable seeds at maturity; all of them became permeable during the dry storage and began to germinate immediately after placing them on a moist substrate. Physical dormancy of other species, e.g. Pelargonium zonale, Pelargonium vitifolium or Geranium pratense, was not affected by dry storage. Thus, physical dormancy is a diversely differentiated feature in Geraniaceae with regard to both percentages of impermeable seeds at maturity and maintenance of dormancy under particular conditions.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2002

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

Abrams, M.D. and Dickmann, D.I. (1982) Early revegetation of clear-cut and burned jack pine sites in northern lower Michigan. Canadian Journal of Botany 60, 946954.CrossRefGoogle Scholar
Allen, P.S. and Meyer, S.E. (1998) Ecological aspects of seed dormancy loss. Seed Science Research 8, 183191.CrossRefGoogle Scholar
Bachthaler, E. (1974) Über die Keimung der Pelargonium zonale-Samen. Gartenwelt 74, 501503.Google Scholar
Bachthaler, E. (1984) Brechung der Hartschaligkeit bei Sämlingspelargonien. Deutscher Gartenbau 38, 4647.Google Scholar
Baskin, C.C. and Baskin, J.M. (1998) In 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. (2000) Evolutionary considerations of claims for physical dormancy-break by microbial action and abrasion by soil particles. Seed Science Research 10, 409413.CrossRefGoogle Scholar
Bevilacqua, L.R., Fossati, F. and Dondero, G. (1987) ‘Callose’ in the impermeable seed coat of Sesbania punicea. Annals of Botany 59, 335341.CrossRefGoogle Scholar
Bhalla, P.L. and Slattery, H.D. (1984) Callose deposits make clover seeds impermeable to water. Annals of Botany 53, 125128.CrossRefGoogle Scholar
Boesewinkel, F.D. (1997) Seed structure and phylogenetic relationships of the Geraniales. Botanische Jahrbücher für Systematik 119, 277291.Google Scholar
Christiansen, M.N. and Moore, R.P. (1958) Seed coat structural differences that influence water uptake and seed quality in hard seed cotton. Agronomy Journal 51, 582584.CrossRefGoogle Scholar
Egley, G.H., Paul, R.N. and Lax, A.R. (1986) Seed coat imposed dormancy: Histochemistry of the region controlling onset of water entry into Sida spinosa seeds. Physiologia Plantarum 67, 320327.CrossRefGoogle Scholar
Fenner, M. (1985) Seed ecology. London, Chapman and Hall.CrossRefGoogle Scholar
Graaf, J.L. and van Staden, J. (1983) The effect of different chemical and physical treatments on seed coat structure and seed germination of Sesbania species. Zeitschrift für Pflanzenphysiologie 112, 221230.CrossRefGoogle Scholar
Granström, A. and Schimmel, J. (1993) Heat effects on seeds and rhizomes of a selection of boreal forest plants and potential reaction to fire. Oecologia 94, 307313.CrossRefGoogle ScholarPubMed
Harris, W.M. (1983) On the development of the macrosclereids in seed coats of Pisum sativum L. American Journal of Botany 70, 15281535.CrossRefGoogle Scholar
Kelly, K.M. and van Staden, J. (1985) Effect of acid scarification on seed coat structure, germination and seedling vigour of Aspalathus linearis. Journal of Plant Physiology 121, 3745.CrossRefGoogle Scholar
Kelly, K.M., van Staden, J. and Bell, W.E. (1992) Seed coat structure and dormancy. Plant Growth Regulation 11, 201209.CrossRefGoogle Scholar
McKeon, G.M. and Mott, J.J. (1982) The effect of temperature on the field softening of hard seed of Stylosanthes humilis and S. hamata in a dry monsoonal climate. Australian Journal of Agricultural Research 33, 7585.CrossRefGoogle Scholar
Meisert, A. (1998) Cytologische, histochemische und ökophysiologische Untersuchungen zur Impermeabilität der Testa bei Geraniaceae-Samen. Dissertation, Hannover University.Google Scholar
Meisert, A., Lehmann, H., Schulz, D., Stelzer, R. and Gierth, M. (1997) Die Lokalisation der Diffusionsbarriere in der Testa hartschaliger Samen von Pelargonium incrassatum mit Hilfe der EDX-Analyse. European Journal of Cell Biology 74 (Suppl. 45). pp 89Google Scholar
Meisert, A., Schulz, D. and Lehmann, H. (1999) Structural features underlying hardseededness in Geraniaceae. Plant Biology 1, 311314.CrossRefGoogle Scholar
Meisert, A., Schulz, D. and Lehmann, H. (2001) The ultrastructure and development of the light line in the Geraniaceae seed coat. Plant Biology 3, 351356.CrossRefGoogle Scholar
Milberg, P. (1994) Germination of up to 129-year old, dry stored seeds of Geranium bohemicum (Geraniaceae). Nordic Journal of Botany 14, 2729.CrossRefGoogle Scholar
Mott, J.J. and McKeon, G.M. (1979) Effect of heat treatments in breaking hardseededness in four species of Stylosanthes. Seed Science and Technology 7, 1525.Google Scholar
Patil, V.N. and Andrews, C.H. (1984) Effectiveness of scarification methods in reducing hard seeds in cotton. Seed Research 12(2), 8286.Google Scholar
Rice, K.J. (1985) Responses of Erodium to varying microsites: The rule of germination cueing. Ecology 66, 16511657.CrossRefGoogle Scholar
Rolston, M.P. (1978) Water impermeable seed dormancy. Botanical Review 44, 365396.CrossRefGoogle Scholar
Schulz, D., Bachthaler, E. and Kunz, U. (1991) Aufbau der Testa bei Pelargonium zonale-Samen. Gartenbauwissenschaft 56, 118126.Google Scholar
Serrato-Valenti, G., Cornara, L., Lotito, S. and Quagliotti, L. (1992) Seed coat structure and histochemistry of Abelmoschus esculentus. Chalazal region and water entry. Annals of Botany 69, 313321.CrossRefGoogle Scholar
Thanos, C.A., Georghiou, K., Kadis, C. and Pantazi, C. (1992) Cistaceae: a plant family with hard seeds. Israel Journal of Botany 41, 251263.Google Scholar
Van der Walt, J.J.A. (1977) Pelargoniums of Southern Africa. pp Cape Town, Purnell and Sons.Google Scholar
Van der Walt, J.J.A. and Vorster, P.J. (1988) Pelargoniums of Southern Africa. Vol. 3. Capetown, National Botanic Gardens Kirstenbosch.Google Scholar
Williams, W.A. and Elliott, J.R. (1960) Ecological significance of seed coat impermeability to moisture in crimson, subterreanean and rose clover in a mediterranean-type climate. Ecology 41, 733742.CrossRefGoogle Scholar