Abstract
Allopolyploidization, the process by which divergent parental genomes are combined into a single genome, is an important mode of instantaneous speciation and source of novelty in higher plants in recently glaciated areas. However, although individual allopolyploid plants may be highly heterozygous, a crucial question is whether this heterozygosity remains static as fixed heterozygosity or would be released and expressed in a way such that further diversification and adaptation may take place. In the former case, polyploids may be regarded as evolutionarily dead ends with little significance over time, whereas in the latter case polyploids may be components of divergent, phyletic speciation, just as diploids. In this project, polyploid members of the widespread orchid genus Dactylorhiza are used as study material. Genome restructuring in these polyploids will be described and quantified by means of variation at nuclear microsatellite loci. The diversity patterns obtained will be compared with a relative timescale for the age of various allopolyploid populations obtained from an ongoing study, in which the detailed origins of the allopolyploids are described by means of plastid microsatellite loci. The applicant and two PhD students will be involved in the project. The application covers lab running costs including development of nuclear microsatellite markers, some equipment, and a 50% position as universitetslektor for the applicant.
Sweden