Flower and Fruit Characteristics in Small and Isolated Populations of a Fleshy-Fruited Shrub

Abstract

During a warm period after the last glaciation the fleshy-fruited shrub, Prunus mahaleb, extended its area of distribution from the Mediterranean basin towards central Europe. Under a subsequent cooler climate, and probably increased competition from trees, the species became restricted to steep, south-facing cliffs and scree slopes with a particularly sunny and warm microclimate. Thus, the small relict populations in central Europe have been isolated for about 5000 - 6000 years. To investigate whether or not reproductive traits of P. mahaleb are affected by isolation and population size, several flower and fruit characteristics were sampled in ten populations in Switzerland. A Canonical Correlation Analysis (CCA) based on these reproductive characteristics differentiated the populations. The first CCA axis was determined by flower size, pollination frequency, pulp and seed mass. This ran parallel to increasing precipitation and decreasing altitude. The second axis correlated with the number of fruits per raceme and seed viability, and ran parallel to increasing sunshine. None of the six flower and fruit variables correlated with population size or with the degree of isolation. However, flower size, pollination frequency, pulp and seed mass showed a negative correlation with altitude. The results suggest that, in populations of P. mahaleb in central Europe, climatic conditions explain more of the observed variation in flower and fruit characteristics than population size or degree of isolation.

Nomenclature

Tutin et al. (1964 - 1980)

Altitude - flower size - pollination frequency - population size - Prunus mahaleb - pulp and seed mass - seed viability

References

• 01 Ågren,  J.. (1996);  Population size, pollinator limitation, and seed set in the self-incompatible herb Lythrum salicaria. .  Ecology. 77 1779-1790
• 02 Arroyo,  M. T. K.,, Armesto,  J. J.,, and Primack,  R. B.. (1985);  Community studies in pollination ecology in the high temperate Andes of central Chile. II. Effect of temperature on visitation rates and pollination possibilities.  Plant Systematics and Evolution. 149 187-203
• 03 Bundesamt für Landestopographie . (1982) Klimaatlas der Schweiz. Bern; BFL
• 04 Burga,  C. A., and Perret,  R.. (1998) Vegetation und Klima der Schweiz seit dem jüngeren Eiszeitalter. Thun; Ott
• 05 Cipollini,  M. L., and Levey,  D. J.. (1991);  Why some fruits are green when they are ripe: carbon balance in fleshy fruits.  Oecologia. 88 371-377
• 06 Colas,  B.,, Olivieri,  I.,, and Riba,  M.. (1997);  Centaurea corymbosa, a cliff-dwelling species tottering on the brink of extinction: a demographic and genetic study.  Proceedings National Academy Sciences USA. 94 3471-3476
• 07 Collinge,  S. K.. (1996);  Ecological consequences of habitat fragmentation: implications for landscape architecture and planning.  Landscape and Urban Planning. 36 59-77
• 08 Debussche,  M., and Isenmann,  P.. (1989);  Fleshy fruit characters and the choices of bird and mammal seed dispersers in a Mediterranean region.  Oikos. 56 327-338
• 09 Ellenberg,  H.. (1988) Vegetation ecology of central Europe. Cambridge; Cambridge University Press
• 10 Fenner,  M.. (1985) Seed ecology. London; Chapman and Hall
• 11 Fischer,  M., and Matthies,  D.. (1998 a);  Effects of population size on performance in the rare plant Gentianella germanica. .  Journal of Ecology. 86 195-204
• 12 Fischer,  M., and Matthies,  D.. (1998 b);  RAPD variation in relation to population size and plant fitness in the rare Gentianella germanica (Gentianaceae).  American Journal of Botany. 85 811-819
• 13 Gittins,  R.. (1985) Canonical analysis. A review with applications in ecology. Berlin; Springer
• 14 Goulson,  D.,, Stout,  J. C.,, Hawson,  S. A.,, and Allen,  J. A.. (1998);  Floral display size in comfrey, Symphytum officinale L. (Boraginaceae): relationships with visitation by three bumblebee species and subsequent seed set.  Oecologia. 113 502-508
• 15 Guitián,  J.. (1993);  Why Prunus mahaleb (Rosaceae) produces more flowers than fruits.  American Journal of Botany. 80 1305-1309
• 16 Guitián,  J.. (1994);  Selective fruit abortion in Prunus mahaleb (Rosaceae).  American Journal of Botany. 81 1555-1558
• 17 Guitián,  J.,, Fuentes,  M.,, Bermejo,  T.,, and López,  B.. (1992);  Spatial variation in the interactions between Prunus mahaleb and frugivorous birds.  Oikos. 63 125-130
• 18 Guitián,  J.,, Guitián,  P.,, and Sánchez,  J. M.. (1993);  Reproductive biology of two Prunus species (Rosaceae) in the northwest Iberian peninsula.  Plant Systematics and Evolution. 185 153-165
• 19 Haeupler,  H., and Schönfelder,  P.. (1989) Atlas der Farn- und Blütenpflanzen der Bundesrepublik Deutschland. Stuttgart; Ulmer
• 20 Herrera,  C. M.. (1984);  A study of avian frugivores, bird-dispersed plants, and their interaction in Mediterranean scrublands.  Ecological Monographs. 54 1-23
• 21 Herrera,  C. M.. (1987);  Vertebrate-dispersed plants of the Iberian peninsul: a study of fruit characteristics.  Ecological Monographs. 57 305-331
• 22 Herrera,  C. M.. (1989);  Frugivory and seed dispersal by carnivorous mammals, and associated fruit characteristics in undisturbed Mediterranean habitats.  Oikos. 55 250-262
• 23 Herrera,  C. M., and Jordano,  P.. (1981);  Prunus mahaleb and birds: the high-efficiency seed dispersal system of a temperate fruiting tree.  Ecological Monographs. 51 203-218
• 24 Herrera,  C. M.,, Jordano,  P.,, Guitián,  J.,, and Traveset,  A.. (1998);  Annual variability in seed production by woody plants and the masting concept: Reassessment of principles and relationship to pollination and seed dispersal.  American Naturalist. 152 576-594
• 25 Holderegger,  R.. (1997);  Recent perspectives in conservation biology of rare plants.  Bulletin of the Geobotanical Institute ETH. 63 109-116
• 26 Hoppes,  W. G.. (1987);  Pre- and postforaging movements of frugivorous birds in an eastern deciduous forest woodland, USA.  Oikos. 49 281-290
• 27 Huenneke,  L. F.. (1991) Ecological implications of genetic variation in plant populations. Genetics and conservation of rare plants. Falk, D. A. and Holsinger, K. E., eds. Oxford; Oxford University Press pp. 31-44
• 28 Hulme,  P. E.. (1997);  Post-dispersal seed predation and the establishment of vertebrate dispersed plants in Mediterranean scrublands.  Oecologia. 111 91-98
• 29 Inouye,  D. W., and Pyke,  G. H.. (1988);  Pollination biology in the Snowy Mountains of Australia: comparison with montane Colorado, USA.  Australian Journal of Ecology. 13 191-210
• 30 Jordano,  P.. (1993);  Pollination biology of Prunus mahaleb L.: deferred consequences of gender variation for fecundity and seed size.  Biological Journal of the Linnean Society. 50 65-84
• 31 Jordano,  P.. (1994);  Spatial and temporal variation in the avian-frugivore assemblage of Prunus mahaleb: patterns and consequences.  Oikos. 71 479-491
• 32 Jordano,  P.. (1995);  Frugivore-mediated selection on fruit and seed size: birds and St. Lucie's cherry, Prunus mahaleb. .  Ecology. 76 2627-2639
• 33 Jordano,  P., and Godoy,  J. A.. (2000);  RAPD variation and population genetic structure in Prunus mahaleb (Rosaceae), an animal-dispersed tree.  Molecular Ecology. 9 1293-1305
• 34 Jordano,  P., and Schupp,  E. W.. (2000);  Seed disperser effectiveness: the quantity component and patterns of seed rain for Prunus mahaleb. .  Ecological Monographs. 70 591-615
• 35 Kahmen,  S., and Poschlod,  P.. (2000);  Populations size, plant performance, and genetic variation in the rare plant Arnica montana L. in the Rhön, Germany.  Basic and Applied Ecology. 1 43-51
• 36 Kelly,  P. E., and Larson,  D. W.. (1997);  Dendroecological analysis of the population dynamics of an old-growth forest on cliff-faces of the Niagara Escarpment, Canada.  Journal of Ecology. 85 467-478
• 37 Kirchhofer,  W.. (1982) Klimaatlas der Schweiz. Wabern; Bundesamt für Landestopographie
• 38 Kollmann,  J.. (1994);  Ausbreitungsökologie endozoochorer Gehölzarten.  Veröffentlichungen Projekt “Angewandte Ökologie”. 9 1-212
• 39 Kollmann,  J.. (1997);  Hypotheses on the regeneration niche of fleshy-fruited species in natural forest gaps and edges in central Europe.  Verhandlungen der Gesellschaft für Ökologie. 27 85-91
• 40 Köppler,  D.. (1995);  Vegetationskomplexe von Steppenheide-Physiotopen im Juragebirge.  Dissertationes Botanicae. 249 1-228
• 41 Küppers,  M.. (1992) Changes in plant ecophysiology across a central European hedgerow ecotone. Landscape boundaries. Hansen, A, J. and di Castri, F., eds. Berlin; Springer pp. 285-303
• 42 Leishman,  M. R., and Westoby,  M.. (1994);  The role of large seed size in shaded conditions.  Functional Ecology. 8 205-214
• 43 Loeschcke,  V.,, Tomiuk,  J.,, and Jain,  S. K.. (1994) Conservation Genetics. Basel; Birkhäuser
• 44 Legendre,  P., and Legendre,  L.. (1998) Numerical Ecology, 2nd ed. Amsterdam; Elsevier
• 45 Manly,  B.. (1997) Randomization, bootstrap and Monte Carlo methods in biology, 2nd ed. London; Chapman and Hall pp. 1171-1184
• 46 Menges,  E. S.. (1991);  Seed germination percentage increases with population size in a fragmented prairie species.  Conservation Biology. 5 158-164
• 47 Moor,  M.. (1962) Einführung in die Vegetationkunde der Umgebung Basels. Basel; Schwabe
• 48 Moor,  M.. (1979);  Das Felsenbirnen-Gebüsch (Cotoneastro-Amelanchieretum), eine natürliche Mantelgesellschaft im Jura.  Phytocoenologia. 6 388-402
• 49 Moore,  R. P.. (1973) Tetrazolium staining for assessing seed quality. Seed ecology. Heydecker, W., ed. London; Butterworths pp. 347-366
• 50 Müller,  T.. (1986);  Prunus mahaleb-Gebüsche.  Abhandlungen des Westfälischen Museums Naturkunde. 48 143-155
• 51 Ouborg,  N. J., and Treuren,  R.. (1995);  Variation in fitness-related characters among small and large populations of Salvia pratensis. .  Journal of Ecology. 83 369-380
• 52 Oostermeijer,  J. G. B.. (1996) Population size, genetic variation, and related parameters in small, isolated plant populations: a case study. Species survival in fragmented landscapes. Settele, J., Margules, C. R., Poschlod, P., and Henle, K., eds. Dordrecht; Kluwer pp. 61-68
• 53 Oostermeijer,  J. G. B.,, van Eijck,  M. W.,, and den Nijs,  J. C. M.. (1994);  Offspring fitness in relation to population size and genetic variation in the rare perennial plant species Gentiana pneumonanthe (Gentianaceae).  Oecologia. 97 289-296
• 54 Piper,  J. K.. (1986);  Germination and growth of bird-dispersed plants: effects of seed size and light on seedling vigor and biomass allocation.  American Journal of Botany. 73 959-965
• 55 Plitmann,  U.. (1994);  Assessing functional reproductive traits from herbarium material: the test case of pollen tubes in pistils of Polemoniaceae. .  Taxon. 43 63-69
• 56 Primack,  R. B.. (1987);  Relationships among flowers, fruits, and seeds.  Annual Review of Ecology and Systematics. 18 409-430
• 57 SAS . (1989 - 1997) JMP manual. Cary, NC; SAS Institute
• 58 Saunders,  D. A.,, Hobbs,  R. J.,, and Margules,  C. R.. (1991);  Biological consequences of ecosystem fragmentation: a review.  Conservation Biology. 5 18-32
• 59 Schneller,  J. J., and Holderegger,  R.. (1996);  Genetic variation in small isolated fern populations.  Journal of Vegetation Science. 7 113-120
• 60 Scholz,  H., and Scholz,  I.. (1995) Prunus mahaleb. Gustav Hegi - Illustrierte Flora von Mitteleuropa, 3. Ed., Vol. 4.2 b. Concert, H. J. et al., eds. Berlin; Blackwell pp. 472-475
• 61 Schreiber,  K.-F.. (1977) Wärmegliederung der Schweiz. Bern; Eidgenössisches Justiz- u. Polizeidepartement
• 62 Settele,  J.,, Margules,  C. R.,, Poschlod,  P.,, and Henle,  K.. (1996) Species survival in fragmented landscapes. Dordrecht; Kluwer
• 63 Stiles,  E. W.. (1989) Fruits, seeds and dispersal agents. Plant-animal-interactions. Abrahamson, W. G., ed. New York; McGraw-Hill pp. 87-122
• 64 Tutin,  T. G.,, Heywood,  V. H.,, Burges,  N. A.,, Valentine,  D. H.,, Walters,  S. M.,, and Webb,  D. A.. (1964 - 1976) Flora Europaea, Vol. 1 - 4. Cambridge; Cambridge University Press
• 65 Vaughton,  G., and Ramsey,  M.. (1998);  Floral display, pollinator visitation and reproductive success in the dioecious perennial herb Wurmbea dioica (Liliaceae).  Oecologia. 115 93-101
• 66 Waddington,  K. D.. (1983) Foraging behavior of pollinators. Pollination biology. Real, L., ed. Orlando; Academic Press pp. 213-239
• 67 Welten,  M., and Sutter,  R.. (1982) Verbreitungsatlas der Farn- und Blütenpflanzen der Schweiz. Basel; Birkhäuser
• 68 Westrich,  P.. (1989) Die Wildbienen Baden-Württembergs. Stuttgart; Ulmer
• 69 Zar,  J. H.. (1996) Biostatistical analysis. Upper Saddle River; Prentice-Hall

Section Editor: G. Gottsberger