Skip to main content Accessibility help
×
Home

Loss of desiccation tolerance during germination in neo-tropical pioneer seeds: implications for seed mortality and germination characteristics 

  • Matthew I. Daws (a1) (a2), Sheina Bolton (a1), David F.R.P. Burslem (a1), Nancy C. Garwood (a3) and Christopher E. Mullins (a1)...

Abstract

Orthodox, desiccation-tolerant seeds lose desiccation tolerance during germination. Here, we quantify the timing of the loss of desiccation tolerance, and explore the implications of this event for seed mortality and the shape of germination progress curves for pioneer tree species. For the nine species studied, all seeds in a seedlot lost desiccation tolerance after the same fixed proportion of their time to germination, and this proportion was fairly constant across the species (0.63–0.70). The loss of desiccation tolerance after a fixed proportion of the time to germination has the implication that the maximum number of seeds in a seedlot that can be killed by a single drying event during germination (Mmax) increases with an increasing time to 50% germination (t50) and an increasing slope of the germination progress curve. Consequently, to prevent the seed population from becoming highly vulnerable to desiccation-induced mortality, species with a greater t50 would be expected to have a shallower germination progress curve. In conclusion, these data suggest that the loss of desiccation tolerance during germination may constitute a significant, but previously unexplored, source of mortality for seeds in seasonal environments with unpredictable rainfall.

Copyright

Corresponding author

*Correspondence Fax: +44(0)1444894110 Email: m.daws@rbgkew.org.uk

Footnotes

Hide All

Presented at the Fifth International Workshop, Desiccation Tolerance and Sensitivity of Seeds and Vegetative Plant Tissues, Drakensberg, South Africa, 14–21 January 2007.

 

Footnotes

References

Hide All
Acuna, P.I. and Garwood, N.C. (1987) Effect of light and scarification on the germination of five species of tropical secondary trees. Revista de Biologia Tropicale 35, 203207.
Augspurger, C.K. (1979) Irregular rain cues and the germination and seedling survival of a Panamanian shrub (Hybanthus prunifolius). Oecologia 44, 5359.
Augspurger, C.K. (1983) Offspring recruitment around tropical trees: changes in cohort distance with time. Oikos 40, 189196.
Becker, P., Rabenold, P.E., Idol, J.R. and Smith, A.P. (1988) Water potential gradients for gaps and slopes in a Panamanian tropical moist forest's dry season. Journal of Tropical Ecology 4, 173184.
Blain, D. and Kellman, M. (1991) The effect of water supply on tree seed germination and seedling survival in a tropical seasonal forest in Veracruz, Mexico. Journal of Tropical Ecology 7, 6983.
Bond, W.J., Honig, M. and Maze, K.E. (1999) Seed size and seedling emergence: an allometric relationship and some ecological implications. Oecologia 120, 132136.
Boubriak, I., Kargiolaki, H., Lyne, L. and Osborne, D.J. (1997) The requirement for DNA repair in desiccation tolerance of germinating embryos. Seed Science Research 7, 97105.
Bruggink, T. and van der Toorn, P. (1995) Induction of desiccation tolerance in germinated seeds. Seed Science Research 5, 14.
Buitink, J., Vu, B.L., Satour, P. and Leprince, O. (2003) The re-establishment of desiccation tolerance in germinated radicles of Medicago truncatula Gaertn. seeds. Seed Science Research 13, 273286.
Buitink, J., Leger, J.J., Guisle, I., Vu, B.L., Wuilleme, S., Lamirault, G., Le Bars, A., Le Meur, N., Becker, A., Küster, H. and Leprince, O. (2006) Transcriptome profiling uncovers metabolic and regulatory processes occurring during the transition from desiccation-sensitive to desiccation-tolerant stages in Medicago truncatula seeds. Plant Journal 47, 735750.
Croat, T.B. (1978) Flora of Barro Colorado Island. Stanford, USA, Stanford University Press.
Dalling, J.W., Swaine, M.D. and Garwood, N.C. (1998) Dispersal patterns and seed bank dynamics of pioneer trees in moist tropical forest. Ecology 79, 564578.
Dalling, J.W., Lovelock, C.E. and Hubbell, S.P. (1999) Growth responses of seedlings of two neotropical pioneer species to simulated forest gap environments. Journal of Tropical Ecology 15, 827839.
Daws, M.I. (2002) Mechanisms of plant species coexistence in a semi-deciduous tropical forest in Panamá. PhD thesis, University of Aberdeen, UK.
Daws, M.I., Burslem, D.F.R.P., Crabtree, L.M., Kirkman, P., Mullins, C.E. and Dalling, J.W. (2002a) Differences in seed germination responses may promote coexistence of four sympatric Piper species. Functional Ecology 16, 258267.
Daws, M.I., Mullins, C.E., Burslem, D.F.R.P., Paton, S.R. and Dalling, J.W. (2002b) Topographic position affects the water regime in a semideciduous tropical forest in Panamá. Plant and Soil 238, 7990.
Daws, M.I., Pearson, T.R.H., Burslem, D.F.R.P., Mullins, C.E. and Dalling, J.W. (2005) Effects of topographic position, leaf litter and seed size on seedling demography in a semi-deciduous tropical forest in Panamá. Plant Ecology 179, 93105.
Daws, M.I., Orr, D., Burslem, D.F.R.P. and Mullins, C.E. (2006) Effect of high temperature on chalazal plug removal and germination in Apeiba tibourbou Aubl. Seed Science and Technology 34, 221225.
Daws, M.I., Ballard, C., Mullins, C.E., Garwood, N.C., Murray, B., Pearson, T.R.H. and Burslem, D.F.R.P. (2007) Allometric relationship between seed mass and seedling characteristics reveal trade-offs for neotropical pioneer species. Oecologia (in press).
Dietrich, W.E., Windsor, D.M. and Dunne, T. (1982) Geology, climate and hydrology of Barro Colorado Island. pp. 2146in Leigh, E.G.; Rand, A.S.; Windsor, D.M. (Eds) The ecology of a tropical forest: Seasonal rhythms and long-term changes. Washington, DC, Smithsonian Institution Press.
Doussi, M.A. and Thanos, C.A. (2002) Ecophysiology of seed germination in Mediterranean geophytes. 1. Muscari spp. Seed Science Research 12, 193201.
Engelbrecht, B.M.J., Dalling, J.W., Pearson, T.R.H., Wolf, R.L., Gálvez, D.A., Koehler, T., Tyree, M.T. and Kursar, T.A. (2006) Short dry spells in the wet season increase mortality of tropical pioneer seedlings. Oecologia 148, 258269.
Evenari, M., Shanan, L. and Tadmor, N. (1971) The Negev: The challenge of a desert. Cambridge, Massachusetts, Harvard University Press.
Garwood, N.C. (1983) Seed germination in a seasonal tropical forest in Panama: a community study. Ecological Monographs 53, 159181.
Harper, J.L. (1977) Population biology of plants. London, Academic Press.
Hong, T.D. and Ellis, R.H. (1992) The survival of germinating orthodox seeds after desiccation and hermetic storage. Journal of Experimental Botany 43, 239247.
Kermode, A. and Finch-Savage, W.E. (2002) Desiccation sensitivity in orthodox and recalcitrant seeds in relation to development. pp. 149184in Black, M.; Pritchard, H.W. (Eds) Desiccation and survival in plants: Drying without dying. Wallingford, UK, CABI Publishing.
Leigh, E.G. (1999) Tropical forest ecology: A view from Barro Colorado Island. Oxford, UK, Oxford University Press.
Leigh, E.G., Rand, A.S. and Windsor, D.M. (1982) The ecology of a tropical forest: Seasonal rhythms and long-term changes. Washington, DC, Smithsonian Institution Press.
Lin, T.-P., Yen, W.-L. and Chien, C.-T. (1998) Disappearance of desiccation tolerance of imbibed crop seeds is not associated with the decline of oligosaccharides. Journal of Experimental Botany 49, 12031212.
Osborne, D.J. and Boubriak, I.I. (1994) DNA and desiccation tolerance. Seed Science Research 4, 175185.
Pammenter, N.W., Berjak, P., Wesley-Smith, J. and Vander Willigen, C. (2002) Experimental aspects of drying and recovery. pp. 93110in Black, M.; Pritchard, H.W. (Eds) Desiccation and survival in plants: Drying without dying. Wallingford, UK, CABI Publishing.
Pearson, T.R.H., Burslem, D.F.R.P., Mullins, C.E. and Dalling, J.W. (2002) Germination ecology of neotropical pioneers: interacting effects of environmental conditions and seed size. Ecology 83, 27982807.
Pearson, T.R.H., Burslem, D.F.R.P., Goeriz, R.E. and Dalling, J.W. (2003) Regeneration niche partitioning in neotropical pioneers: effects of gap size, seasonal drought and herbivory on growth and survival. Oecologia 137, 456465.
Reisdorph, N.A. and Koster, K.L. (1999) Progressive loss of desiccation tolerance in germinating pea (Pisum sativum) seeds. Physiologia Plantarum 105, 266271.
Smith, B.D. (1998) The emergence of agriculture. New York, Scientific American Library.
Swaine, M.D. and Whitmore, T.C. (1988) On the definition of ecological species groups in tropical rain forests. Vegetatio 75, 8186.
Thanos, C.A. and Doussi, M.A. (1995a) Ecophysiology of seed-germination in endemic Labiates of Crete. Israel Journal of Plant Sciences 43, 227237.
Thanos, C.A., Kadis, C.C. and Skarou, F. (1995b) Ecophysiology of germination in the aromatic plants thyme, savory and oregano (Labiatae). Seed Science Research 5, 161170.
Vázquez-Yanes, C. and Smith, H. (1982) Phytochrome control of seed germination in the tropical rain forest pioneer trees Cecropia obtusifolia and Piper auritum and its ecological significance. New Phytologist 92, 477485.
Veenendaal, E.M., Swaine, M.D., Agyeman, V.K., Blay, D., Abebrese, I.K. and Mullins, C.E. (1995) Differences in plant and soil water relations in and around a forest gap in West Africa during the dry season may influence seedling establishment and survival. Journal of Ecology 83, 8390.

Keywords

Loss of desiccation tolerance during germination in neo-tropical pioneer seeds: implications for seed mortality and germination characteristics 

  • Matthew I. Daws (a1) (a2), Sheina Bolton (a1), David F.R.P. Burslem (a1), Nancy C. Garwood (a3) and Christopher E. Mullins (a1)...

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed