Soil diaspore bank of ephemeral plants
Abstract
Genetic and/or phenotypic variation is required for populations to adapt to environmental change. Many annual, fugitive plant species maintain a persistent soil diaspore bank (buried viable diaspores), which adds an additional, temporal component to geographically structured genetic and phenotypic variation. Persistent soil diaspore banks may buffer local populations against dramatic changes in genetic composition occurring in conjunction with severe fluctuations in population size (genetic drift), they may retard response to selection (i.e., buffer local populations against selection), and they may act as a source of genetic novelty and may thus increase the evolutionary potential of populations, because aging of seeds is accompanied by chromosome breakage and genic mutation through progressive cleavage of DNA into fragments of lower molecular weight. Persistent soil diaspore banks are characteristic of species of ephemeral, semi-aquatic environments (communities of dwarf rushes). In Europe, these communities are declining. Historically important retreat areas of populations of dwarf rushes are secondary, man-made fishponds, with a European centre of distribution in the Bohemian Massif. The intensive disturbance regime (flooding, pond management) is expected to exert severe differential selection pressure on populations of dwarf rushes. There is little empirical evidence on the importance and functional significance of persistent soil diaspore banks for maintaining genetic and phenotypic variation. This project aims at illuminating the role of the persistent soil diaspore bank as an integral part of the life history of ephemeral, semi-aquatic plant species. The objectives and hypotheses are structured around two main components of variation in populations: (1) genetic variation as opposed to (2) variation in phenotypic and life history traits. The first objective is the study of the distribution of genetic variation within and among soil diaspore bank and surface population at study sites with different disturbance/management regimes in relation to total genetic diversity in the species. The second objective is the study of variation in quantitative traits associated with fitness as opposed to the supposedly neutral genetic variation. We aim at testing the hypotheses that adaptation processes in local populations lead to locally adapted phenotypes and that ephemeral, semi-aquatic plant species have adapted to natural water-level oscillations and irregular discharge of pond water through increased phenotypic plasticity by assessing the contribution of genotype vs. environment (availability of water) for observed phenotypic variation. Our species of interest is Cyperus fuscus (Cyperaceae), a character species of communities of dwarf rushes. We will take soil diaspore bank samples and compare soil diaspore bank vs. surface populations for their genetic composition (AFLPs and SSRs) and phenotypic variation and plasticity.
keywords Cyperus fuscus Phenotypic plasticity Soil seed bank Microsatellites Isoëto-Nanojuncetea habitats AFLP
Publikationen
Ex-situ conservation: Auswirkungen der Langzeitlagerung von Diasporen in einer Seedbank auf ihre Keimfähigkeit am Beispiel von Cyperus fuscus (Cyperaceae)
Autoren: Bernhardt, K.-G., Böckelmann, J., Tremetsberger, K., Tumpold, R., Wernisch M. Jahr: 2014
Conference & Workshop proceedings, paper, abstract
Fitness, plasticity, and the role of the diaspore bank of the semiaquatic Cyperus fuscus in near natural and secondary habitats
Autoren: Böckelmann, J., Bernhardt, K.-G.; Tremetsberger , K., Šumberová, K. Jahr: 2015
Conference & Workshop proceedings, paper, abstract
Fitness, plasticity, and the role of diaspore bank of the limose Cyperus fuscus in river and secondary habitats
Autoren: Böckelmann, J., Bernhardt, K.-G., Tremetsberger, K,. Šumberová, K. Jahr: 2016
Conference & Workshop proceedings, paper, abstract
Mikrosatellitenanalyse bei Cyperus fuscus, einem typischen Vertreter der Zwergbinsengesellschaften
Autoren: Böckelmann, J., Tremetsberger, K., Kohl, G., Šumberová, K., Bernhardt, K.-G. Jahr: 2016
Conference & Workshop proceedings, paper, abstract
Soil diaspore bank of ephemeral plants: Die Diasporenbank im Boden von ephemeren Pflanzen
Autoren: Bernhardt, K.-G., Böckelmann, J., Tremetsberger, K. Jahr: 2016
Forschungsbericht (extern. Auftraggeber)
Project staff
Karl Georg Bernhardt
Univ.-Prof. i.R. Dipl.Geograph Dr. Karl Georg Bernhardt
karl-georg.bernhardt@boku.ac.at
Tel: +43 1 47654-83111
Project Leader
01.01.2012 - 31.12.2015
Heinrich Grausgruber
Ao.Univ.Prof. Dipl.-Ing. Dr.nat.techn. Heinrich Grausgruber
heinrich.grausgruber@boku.ac.at
Tel: +43 1 47654-95711
Sub Projectleader
01.01.2012 - 31.12.2015
Karin Tremetsberger
Priv.-Doz. Mag. Dr. Karin Tremetsberger
karin.tremetsberger@boku.ac.at
Tel: +43 1 47654-83113
Sub Projectleader
01.01.2012 - 31.12.2015
BOKU partners
External partners
Academy of Sciences of the Czech Republic (ASCR), Institute of Botany
Dr. Kateřina Šumberová
partner