Ecological, morphological and allozymic differentiation between diploid and tetraploid knapweeds (Centaurea jacea) from a contact zone in the Belgian Ardennes
Hardy, O. J.; Vanderhoeven, SONIA; De Loose, M.et al.
[en] In the northeastern part of Belgium, the Centaurea jacea complex shows extensive morphological variation and is represented by a diploid (2n = 22) and a tetraploid (2n = 44) cytotype. Polysomic inheritance of allozyme markers in the tetraploids, suggesting autopolyploidy, is here demonstrated for the first time. In order to test whether the tno cytotypes occupy distinct habitats and possess different gene pools, patterns of allozymic and morphological variation were investigated in relation to ploidy level and site characteristics in 26 populations from the Belgian Ardennes. The two cytotypes showed a parapatric distribution, the diploids occurring at higher elevations (mostly above 500 m) than the tetraploids (mostly below 500 m). Three mixed populations were found near the contact zone of the two cytotypes. Within the mixed populations no triploid plant and no evidence for gene flow between cytotypes were found, despite widely overlapping flowering periods. The two cytotypes can be distinguished on the basis of morphological traits and enzymatic gene pools. The congruence of morphological and allozymic variation with chromosome numbers suggests a secondary contact between the two cytotypes with limited gene flow between them. The origin and persistence of the parapatric distribution are discussed.
Ecological, morphological and allozymic differentiation between diploid and tetraploid knapweeds (Centaurea jacea) from a contact zone in the Belgian Ardennes
Blaise S, Cartier D, Reynaud J. 1991. Evolution and differentiation of Lotus corniculatus/Lotus alpinus populations from French South-Western Alps. I. Morphologic and cyanogenic variations. Evolutionary Trends in Plants 5: 137-148.
Bretagnolle F, Felber F, Calame FG, Küpfer P. 1998. La polyploïdie chez les plantes. Botanica Helvetica 108: 5-37.
Bretagnolle F, Thompson JD. 1995. Gametes with the somatic chromosome number: mechanisms of their formation and role in the evolution of autopolyploid plants. New Phytologist 129: 1-22.
Bretagnolle F, Thompson JD. 1996. An experimental study of ecological differences in winter growth between sympatric diploid and autotetraploid Dactylis glomerata. Journal of Ecology 84: 343-351.
Briquet J. 1931. Composées Cynaroïdées. In: Burnat E, Briquet J, Cavillier K, eds. Flore des Alpes-Maritimes, vol. III. Geneva, Switzerland, Georg et Cie.
Brunsberg K. 1977. Biosystematics of the Lathyrus pratensis complex. Opera Botanica 42: 1-78.
Burton TL, Husband BC. 1999. Population cytotype structure in the polyploid Galax ureolata (Diapensiaceae). Heredity 82: 381-390.
Demarly Y. 1963. Génétique des rétraploïdes et amélioration des plantes. Annales de l'Amélioration des Plantes 13: 307-400.
Dostal J. 1976. Centaurea L. In: Tutin TG et al., eds. Flora Europaea. Cambridge, UK: Cambridge University Press, 254-301.
Duvigneaud J, Saintenoy-Simon J. 1997. Centaurea nigra. Sa description, son écologie, sa distribution dans nos régions. Adoxa 15/16: 29-31.
Ellenberg H. 1974. Zeigerwerte der Gefässpflanzen Mitteleuropas. Scripta Geobotanica 9: 2-111.
Felber-Girard M, Felber F, Buttler A. 1996. Habitat differentiation in a narrow hybrid zone between diploid and tetraploid Anthoxanthum alpinum. New Phytologist 133: 531-540.
Galbraith DW, Harkins KR, Maddox JM, Ayres NM, Sharma DP, Firoozabadi E. 1983. Rapid flow cytometric analysis of the cell cycle in intact plant tissues. Science 220: 1049-1051.
Gardou C. 1972. Recherches biosystématiques sur la Section Jacea Cass. et quelques sections voisines du genre Centaurea L. en France et dans les régions limitrophes. Feddes Repertorium 83: 311-472.
Gauthier P, Lumaret R, Bédécarrats A. 1998. Genetical variation and gene flow in Alpine diploid and tetraploid populations of Lotus [L. alpinus (DC.) Schleicher/L. corniculatus L.]. I. Insights from morphological and allozyme markers. Heredity 80: 683-693.
Guinochet M, de Vilmorin R. 1982. Flore de France. 4. Paris, France: Centre National de la Recherche Scientifique.
Husband BC, Schemske DW. 1998. Cytotype distribution at a diploid-tetraploid contact zone in Chamerion (Epilobium) angustifolium (Onagraceae). American Journal of Botany 85: 1688-1694.
Kay QON. 1969. The origin and distribution of diploid and tetraploid Tripleurospermum inodorum (L.) Schultz Bip. Watsonia 7: 130-141.
Lambinon J, De Langhe JE, Delvosalle L, Duvigneaud J. 1992. Nouvelle flore de la Belgique, du Grand-Duché de Luxembourg, du Nord de la France et des régions voisines (Ptéridophytes et Spermatophytes). Meise, Belgium: Jardin botanique national de Belgique.
Levin DA. 1975. Minority cytotype exclusion in local plant populations. Taxon 24: 35-43.
Lumaret R. 1988. Adaptive strategies and ploidy levels. Oecologia Plantarum 9: 83-93.
Lumaret R, Barrientos E. 1990. Phylogenetic relationships and gene flow between sympatric diploid and tetraploid plants of Dactylis glomerata (Gramineae). Plant Systematics and Evolution 169: 81-96.
Lumaret R, Guillerm JL, Delay J, Ait Lhaj Loutfi A, Izco J, Jay M. 1987. Polyploidy and habitat differentiation in Dactylis glomerata L. from Galicia (Spain). Oecologia 73: 436-446.
Lumaret R, Hanotte C. 1987. Mise en évidence d'un écotype de dactyle (Dactylis glomerata L.) de pelouses dolomitiques subalpines dans les Grisons (Suisse): origine et échanges géniques avec les dactyles des prairies adjacentes. Oecologia Plantarum 8: 3-20.
Marsden-Jones EM, Turrill WB. 1952. British knapweeds. London, UK: Ray Society.
Nei M. 1987. Molecular evolutionary genetics. New York, USA: Columbia University Press.
Petit C, Bretagnolle F, Felber F. 1999. Evolutionary consequences of diploid-polyploid hybrid zones in wild species. Trends in Ecology and Evolution 14: 306-311.
Petit C, Lesbros P, Ge X, Thompson JD. 1997. Variation in flowering phenology and outcrossing rate across a contact zone between diploid and tetraploid Arrhenatherum elatius. Heredity 79: 31-40.
Petit C, Thompson JD. 1997. Variation in phenotypic response to light availability between diploid and tetraploid populations of the perennial grass Arrhenatherum elatius from open and woodland sites. Journal of Ecology 85: 657-667.
Ramsey J, Schemske DW. 1998. Pathways, mechanisms, and rates of polyploid formation in flowering plants. Annual Review of Ecology and Systematics 29: 467-501.
Rodriguez DJ. 1996. A model for the establishment of polyploidy in plants. American Naturalist 147: 33-46.
Ronfort J, Jenczewski E, Bataillon T, Rousset F. 1998. Analysis of population structure m autotetraploid species. Genetics 150: 921-930.
Rothera SL, Davy AJ. 1986. Polyploidy and habitat differentiation in Deschampsia cespitosa. New Phytologist 102: 449-467.
Saarisalo-Taubert A. 1966. A study of hybridization in Centaurea sect. Jacea in eastern Fennoscandia. Annales botanici fennici 3: 86-95.
Segraves KA, Thompson JN, Soltis PS, Soltis DE. 1999. Multiple origins of polyploidy and the geographic structure of Heuchera grossulariifolia. Molecular Ecology 8: 253-262.
Sommer S. 1990. Isozymanalyse zur Ermittlung genetischer variabilität und mikroevolutiver prozesse bei Centaurea sect. Jacea (Asteraceae). PhD thesis, Universität Bayreuth, Bayreuth, Germany.
Stebbins GL, Zohary D. 1959. Cytogenetic and evolutionary studies in the genus Dactylis. University of California Publications in Botany 31: 1-40.
Thompson JD, Lumaret R. 1992. The evolutionary dynamics of polyploid plants: origins, establishment and persistence. Trends in Ecology and Evolution 7: 302-307.
Tyler B, Borrill M, Chorlton K. 1978. Studies in Festuca. X. Observations on germination and seedling cold tolerance in diploid Festuca pratensis and tetraploid F. pratensis var. apennina in relation to their altitudinal distribution. Journal of Applied Ecology 15: 219-226.
Van Dijk P, Bakx-Schotman T. 1997. Chloroplast DNA phylogeography and cytotype geography in autopolyploid Plantago media. Molecular Ecology 6: 345-352.
Van Dijk P, Bijlsma R. 1994. Simulations of flowering time displacement between two cytotypes that form inviable hybrids. Heredity 72: 522-535.
Van Dijk P, Hartog M, Van Delden W. 1992. Single cytotype areas in autopolyploid Plantago media L. Biological Journal of the Linnean Society 46: 315-331.
Van Soest JL. 1947. Centaurea sectie Jacea en het voorkomen in Nederland. Nederlandsch Kruidkundig Archief 54: 68-106.
Weeda EJ, Westra R, Westra C, Westra T. 1991. Nederlandse oecologische flora. Wilde planten en hun relaties. Vol. 4. Hilversum, The Netherlands: IVN.