Abstract Detail

Species delimitation in polyploid complexes

Wagner, Natascha [1], Hörandl, Elvira [1].

Tetra, hexa, octo – dealing with polyploid species in genus Salix L. subg. Chamaetia/Vetrix in times of big data.

Plant evolution is shaped by a bunch of different processes, for instance hybridization, introgression and polyploidization. Especially polyploidization seems to be an important factor that is supposed to be responsible for about 15% of speciation of land plants. However, despite this knowledge, dealing with taxa that underwent processes of reticulate evolution and/or polyploidization in molecular systematics is still challenging, even at the rise of NGS tools. However, to understand these processes, we study the genus Salix (c. 450 species), which is an interesting model system to analyse the effects of ancient and recent hybridization, reticulate evolution, and polyploidization. Especially the big and species-rich clade of northern hemisphere shrub willows (subg. Chamaetia and subg. Vetrix) is interesting due to morphological plasticity of the species contrasting the molecular purity, a high degree of polyploidy and frequent interspecific hybridization. The clade contains tiny shrub willows adapted to arctic-alpine regions as well as bigger shrubs and trees. We used the next generation sequencing approach RAD sequencing (Restriction site Associated DNA sequencing) to analyse the phylogenetic relationships of about 50 Eurasian, Asian and American species representing the Chamaetia/Vetrix clade. By mining a large number of single-nucleotide polymorphisms (SNPs) we could reconstruct the phylogenetic history of the genus including a rapid radiation in the Pan Himalaya region. The included North American species form a well-supported clade. We will further present the applicability of this genomic marker system to understand evolutionary origin, parentage and diversification of some polyploid willow species by using SNiPloid, a tool to analyse the SNP composition of the polyploid accessions in comparison to its putative parental species.

1 - University of Goettingen, Systematics, Evolution and Biodiversity of Plants, Untere Karspüle 2, Göttingen, 37073, Germany

Keywords:
polyploidization
Next Generation Sequencing
RADseq
phylogenomics.

Presentation Type: Colloquium Presentations
Session: CO01, Species delimitation in polyploid complexes
Location: Tucson J/Starr Pass
Date: Monday, July 29th, 2019
Time: 11:00 AM
Number: CO01009
Abstract ID:172
Candidate for Awards:None