Plant Biol (Stuttg) 2007; 9(6): 683-693
DOI: 10.1055/s-2007-965081
Research Paper

Georg Thieme Verlag Stuttgart KG · New York

Timing of Sexual Reproduction and Reproductive Success in the High-Mountain Plant Saxifraga bryoides L.

U. Ladinig1 , J. Wagner1
  • 1Institute of Botany, University of Innsbruck, Sternwartestraße 15, 6020 Innsbruck, Austria
Further Information

Publication History

Received: February 23, 2006

Accepted: February 16, 2007

Publication Date:
31 May 2007 (online)

Abstract

Saxifraga bryoides L. is one of the plant species reaching the upper limits of distribution for flowering plants in the European Alps. Because of its abundance in the subnival and nival zones, we expected S. bryoides to reproduce efficiently in the highly stochastic climate at higher altitudes. Investigations were carried out at two subnival sites (2650 m and 2880 m a.s.l.) in the Austrian Alps. We studied flowering phenology, dynamics of seed development, and reproductive success in the climatically different years from 2001 - 2004. For a nival plant species, S. bryoides showed a particularly long prefloration period (6 - 9 weeks). From onset of anthesis until seed maturity took an individual flower another 6 - 7 weeks and all individuals at a site 9 - 10 weeks. The length of the prefloration period and seed histogenesis was temperature-dependent, whereas seed maturation seemed to be endogenously controlled. Only in the exceptionally long and warm growing season of 2003 did all fruits mature at a site. In the other years, the onset of winter conditions halted development in many fruits before maturity. The seed/ovule ratio of mature fruits was around 0.7 in all years. The relative reproductive success (RRS) ranged from zero to 0.7, depending on the site and year. In conclusion, S. bryoides needs an unexpectedly long time to undergo reproductive development. Though fruit maturation is uncertain, the high S/O ratio of single intact fruits results in at least a small seed crop in most years. This seems to be sufficient to assure the spread and maintenance of S. bryoides at higher altitudes. As a seed-risk strategist ([Molau, 1993]), S. bryoides would clearly benefit from a prolonged growing season, which might occur more often if climate warming continues.

References

  • 1 Alatalo J. M., Totland O.. Response to simulated climatic change in an alpine and subarctic pollen-risk strategist, Silene acaulis.  Global Change Biology. (1997);  3 74-79
  • 2 Anchisi E.. Quatrième contribution à l'étude de la flore valaisanne.  Bulletin Murithienne. (1985);  102 115-126
  • 3 Billings W. D., Mooney H. A.. The ecology of arctic and alpine plants.  Biological Reviews. (1968);  43 481-529
  • 4 Brochmann C., Håpnes A.. Reproductive strategies in some arctic Saxifraga (Saxifragaceae), with emphasis on the narrow endemic S. svalbardensis and its parental species.  Botanical Journal of the Linnean Society. (2001);  137 31-49
  • 5 Buchner O., Neuner G.. Variability of heat tolerance in alpine plant species measured at different altitudes.  Arctic, Antarctic, and Alpine Research. (2003);  35 411-420
  • 6 Cannell M. G. R., Smith R. I.. Thermal time, chill days and prediction of budburst in Picea sitchensis.  Journal of Applied Ecology. (1983);  20 951-963
  • 7 Cannone N., Gerdol R.. Vegetation as an ecological indicator of surface instability in rock glaciers.  Arctic, Antarctic, and Alpine Research. (2003);  35 384-390
  • 8 Cleve A.. Zum Pflanzenleben in nordschwedischen Hochgebirgen. Bihang till Kungliga Svenska Vetenskapsakademien Handlingar, Vol. 26/III. Stockholm; Norstedt (1901): 1-105
  • 9 Dafni A.. Pollination Ecology. New York; Oxford University Press (1992): 1-250
  • 10 Diggle P. K.. Extreme preformation in alpine Polygonum viviparum: an architectural and developmental analysis.  American Journal of Botany. (1997);  84 154-169
  • 11 Grabherr G., Nagy L., Thompson D. B. A.. An outline of Europe's alpine areas. Nagy, L., Grabherr, G., Körner, C., and Thompson, D. B. A., eds. Alpine Biodiversity in Europe. Ecological Studies 167. Berlin, Heidelberg; Springer (2003): 3-12
  • 12 Gugerli F.. Sexual reproduction in Saxifraga oppositifolia L. and Saxifraga biflora All. (Saxifragaceae) in the Alps.  International Journal of Plant Science. (1997 a);  158 274-281
  • 13 Gugerli F.. Hybridization of Saxifraga oppositifolia and S. biflora (Saxifragaceae) in a mixed alpine population.  Plant Systematics and Evolution. (1997 b);  207 255-272
  • 14 Haughn G., Chaudhury A.. Genetic analysis of seed coat development in Arabidopsis.  Trends in Plant Science. (2005);  10 472-477
  • 15 Herr J. M.. A new clearing-squash technique for the study of ovule development in Angiosperms.  American Journal of Botany. (1971);  58 785-790
  • 16 Huelber K., Gottfried M., Pauli H., Reiter K., Winkler M., Grabherr G.. Phenological responses of snowbed species to snow removal dates in the Central Alps: implications for climate warming.  Arctic, Antarctic, and Alpine Research. (2006);  38 99-103
  • 17 Hodkinson I. D., Bird J.. Host-specific insect herbivores as sensors of climate change in arctic and alpine environments.  Arctic and Alpine Research. (1998);  30 78-83
  • 18 Inouye D., Morales M. A., Dodge G. J.. Variation in timing and abundance of flowering by Delphinium barbeyi Huth (Ranunculaceae): the roles of snowpack, frost, and La Niña, in the context of climate change.  Oecologia. (2002);  130 543-550
  • 19 Johri B. M., Ambegaokar K. B., Srivastava P. S.. Comparative Embryology of Angiosperms, Vol. 1. Berlin, Heidelberg, New York; Springer (1992): 1-614
  • 20 Jones V., Richards P. W.. Biological flora of the British Isles: S. oppositifolia L.  Journal of Ecology. (1956);  44 300-316
  • 21 Kaplan K.. Embryologische, pollen- und samenmorphologische Untersuchungen zur Systematik von Saxifraga (Saxifragaceae).  Bibliotheca Botanica. (1981);  134 1-56
  • 22 Kaplan K.. Saxifragaceae. Weber, H. E., ed. Gustav Hegi - Illustrierte Flora von Mitteleuropa, Vol. 4/2A. Berlin; Blackwell (1995): 130-229
  • 23 Keller F., Körner C.. The role of photoperiodism in alpine plant development.  Arctic, Antarctic, and Alpine Research. (2003);  35 361-368
  • 24 Körner C., Woodward F. I.. The dynamics of leaf extension in plants with diverse altitudinal ranges. II. Field studies in Poa species between 600 and 3200 m altitude.  Oecologia. (1987);  74 279-283
  • 25 Körner C.. Alpine Plant Life, 2nd ed. Berlin, Heidelberg, New York; Springer (2003): 1-349
  • 26 Kudo G.. Effects of snow-free period on the phenology of alpine plants inhabiting snow patches.  Arctic and Alpine Research. (1991);  23 436-443
  • 27 Ladinig U., Wagner J.. Sexual reproduction of the high mountain plant Saxifraga moschata Wulfen at varying lengths of the growing season.  Flora. (2005);  200 502-515
  • 28 Larcher W.. Hochgebirge: An den Grenzen des Wachstums. Morawetz, W., ed. Ökologische Grundwerte in Österreich. Wien; Österreichische Akademie der Wissenschaften (1994): 304-343
  • 29 Larl I., Wagner J.. Timing of reproductive and vegetative development in Saxifraga oppositifolia in an alpine and a subnival climate.  Plant Biology. (2006);  8 155-166
  • 30 Molau U.. Relationships between flowering phenology and life history strategies in tundra plants.  Arctic and Alpine Research. (1993);  25 391-402
  • 31 Molau U.. Phenology and reproductive success in arctic plants: susceptibility to climate change. Oechel, W. C., Callaghan, T., Gilmanov, T., Holten, J. I., Maxwell, B., Molau, U., and Sveinbjörnsson, B., eds. Global Change and Arctic Terrestrial Ecosystems. Ecological Studies 124. Berlin, Heidelberg; Springer (1997): 153-170
  • 32 Molau U., Nordenhäll U., Eriksen B.. Onset of flowering and climate variability in an alpine landscape: a 10-year study from Swedish Lapland.  American Journal of Botany. (2005);  92 422-431
  • 33 Morris W. F., Doak D. F.. Life history of the long-lived gynodioecious cushion plant Silene acaulis (Caryophyllaceae), inferred from size-based population projection matrices.  American Journal of Botany. (1998);  85 784-793
  • 34 Neuner G., Braun V., Buchner O., Taschler D.. Leaf rosette closure in the alpine rock species Saxifraga paniculata Mill.: significance for survival of drought and heat under high irradiation.  Plant, Cell and Environment. (1999);  22 1539-1548
  • 35 Pauli H., Gottfried M., Grabherr G.. Vascular plant distribution patterns at the low-temperature limits of plant life - the alpine-nival ecotone of Mount Schrankogel (Tyrol, Austria).  Phytocoenologia. (1999);  29 297-325
  • 36 Sandvik S., Totland O.. Short-term effects of simulated environmental changes on phenology, reproduction, and growth in the late-flowering snowbed herb Saxifraga stellaris L.  Ecoscience. (2000);  7 201-213
  • 37 Sørensen T.. Temperature relations and phenology of the northeast Greenland flowering plants.  Meddelelser om Grønland. (1941);  125 1-307
  • 38 Stenström M., Molau U.. Reproductive ecology of Saxifraga oppositifolia: phenology, mating system, and reproductive success.  Arctic and Alpine Research. (1992);  24 337-343
  • 39 Stenström M., Gugerli F., Henry G. H. R.. Response of Saxifraga oppositifolia L. to simulated climate change at three contrasting latitudes.  Global Change Biology. (1997);  3 44-54
  • 40 Taschler D., Neuner G.. Summer frost resistance and freezing patterns measured in situ in leaves of major alpine plant growth forms in relation to their upper distribution boundary.  Plant, Cell and Environment. (2004);  27 737-746
  • 41 Wagner J., Mitterhofer E.. Phenology, seed development, and reproductive success of an alpine population of Gentianella germanica in climatically varying years.  Botanica Acta. (1998);  111 159-166
  • 42 Wagner J., Tengg G.. Phänoembryologie der Hochgebirgspflanzen Saxifraga oppositifolia und Cerastium uniflorum.  Flora. (1993);  188 203-212
  • 43 Wiens D.. Ovule survivorship, brood size, life history, breeding systems, and reproductive success in plants.  Oecologia. (1984);  64 47-53

J. Wagner

Institute of Botany
University of Innsbruck

Sternwartestraße 15

6020 Innsbruck

Austria

Email: johanna.wagner@uibk.ac.at

Editor: F. R. Scarano

    >