Institute for Biodiversity and Ecosystem Dynamics

Research Group of Experimental Plant Systematics (IBED-EPS)

Genetic variation within species is the fuel for evolution. Ultimately, all variation is generated by mutation, whether mutations are deleterious (which will be the most common situation), neutral, or beneficial for the functioning of an organism. In the latter case, adaptations can evolve by means of natural selection, which makes variation important for the survival of local populations and ultimately the whole species. Indeed, the Rio World Convention on Biodiversity identified this variation as essential for biodiversity conservation strategies. Loss of variation due to habitat destruction and fragmentation may lead to decreasing population sizes, declining reproductive success and ultimately to extinction.

In many plant species there are other mechanisms by which variation is created. Firstly, hybridization with related species may lead to introgression of genes from one species to another. Thus, genes with a long history of selection in one evolutionary lineage may jump to another species, giving new opportunities for selection and further evolution. Secondly, evolution by means of polyploidisation (the multiplication or fusion of entire genomes) can lead to variation in chromosome numbers within what is then called a 'species complex'. For instance, in the Great Yellow Cress, Rorippa amphibia, diploid plants with 16 (2x8) chromosomes, as well as tetraploid plants with 32 (4x8) chromosomes are found. Once genomes are duplicated, independent evolution of the gene copies may result in further evolution and divergence.

The group Experimental Plant Systematics studies the origin and maintenance of genetic variation in plants, its relationship with the plant's breeding system, and its role in the process of adaptation

Five main research lines

Our research is clustered around the following five main research lines:

  1. Breeding system and metapopulation dynamics of crucifer species (Arabidopsis, Rorippa)
  2. Biosystematics, Evolution and Phylogeny of Polyploid complexes (Rorippa, Taraxacum)
  3. Plant Conservation Biology (Gentiana, Gentianella, Arnica, other endangered species)
  4. Patterns and Processes in populations of tropical montane rain forest species (Tillandsia, Guzmania and other bromeliads)
  5. Crop/Wild relative complexes and GMO Risk Assessment (Lactuca, Cichorium)

The methods used are molecular genetic analyses (DNA, allozymes), experiments (in the field as well under controlled conditions in greenhouse or growth chamber) and modelling (matrix projection models, population viability analysis, quantitative genetic modelling).

The impact of human interference is a recurrent topic within these research lines, although the main focus is on answering fundamental questions on the distribution and functioning of plants. Indeed, in the light of the worldwide biodiversity crisis, it is indispensable to study and document changes in biodiversity. We tackle societal problems by applying the methods and techniques of molecular and experimental ecology to come up with suggestions and solutions for protecting the natural biodiversity at local or global scales. For instance, the effects of the introduction of transgenic agricultural crop races on the performance of wild relatives and on the functioning of the plant community are studied. These so-called 'biosafety assessments' will become increasingly important in the future, when more and more transgenic crops will be developed.

Published by  IBED

12 July 2012