Analysis of phylogenetic relationships of Hordeum (Poaceae) polyploids

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Polyploidy, this means the duplication of entire genomes, is a very important mechanism creating biodiversity in plants. Within the barley genus Hordeum about half of the taxa are polyploids, mostly allopolyploids combining genomes from two or three different parental species. While for the diploid taxa a good hypothesis of phylogenetic relationships already exists, for polyploids few information is available. Knowledge of the phylogeny of a group is indispensable for further analyses of evolutionary or ecological processes. Within the proposed project I will analyze species relationships in Hordeum with three single copy nuclear marker loci by sequencing of cloned PCR products of these regions and using phylogenetic analysis algorithms. For some polyploid groups in-detail studies will be conducted including sequence analysis and genomic in situ hybridization (GISH). The work will result in a better understanding of this important grass genus, will establish new markers regions useful in grass or at least in Triticeae systematics, provide dating of polyploid origins, and will allow further analyses of genomic and ecological changes after or connected with polyploidization.