Abstract Detail

Bryophytes and Lichens on the Edges of Changing Ecosystems

Patel, Nikisha [1], Johnson, Matt [2], Medina, Rafael [3], Goffinet, Bernard [4].

Whole genome duplication and reticulate evolution in the Physcomitrium pyriforme species complex.

Whole genome duplication (WGD) is a mechanism critical to evolutionary change and speciation across the plant tree of life. Both conspecific genome doubling (autopolyploidy) and WGD following hybridization (allopolyploidy) may result in morphologically distinct lineages and hence may contribute significantly to species diversity. However, accurate phylogenetic reconstruction of allopolyploids and their component genomes remains a major challenge. The moss Physcomitrium pyriforme is a widespread species complex found across North America and Europe that exhibits substantial morphological variation, evident in the recognition of 29 synonyms. We hypothesize that this species complex comprises numerous cytotypes resulting from repeated WGD events. We sampled over 200 populations of P. pyriforme across its North American and use a target capture approach to sequence 648 genes to construct a phylogenetic tree establishing relationships among P. pyriforme populations, as well as identify allopolyploid populations by assessing heterozygosity across genes. We find evidence for three clades within monophyletic North American P. pyriforme as well as the presence of 38 allopolyploid populations. Here we utilize the significant genetic resources generated by target capture sequencing, as well as a novel approach to subgenome allele phasing, to reconstruct the reticulate evolutionary history of allopolyploid lineages by identifying hybrid progenitors. WGD plays a substantial role in the evolution of the P. pyriforme complex and provides evidence for morphologically cryptic speciation via polyploidy.

1 - University of Connecticut
2 - Texas Tech University, Biological Sciences, 2901 Main Street, Ms3131, Lubbock, TX, 79409, United States
3 - Universidad Complutense De Madrid, Biodiversidad, Ecología Y Evolución, C/ José Antonio Novais, 12, Botánica, Madrid, M, 28040, Spain
4 - University Of Connecticut, Department Of Ecology & Evolutionary Biology, 75 N. Eagleville Road, U-3043, Storrs, CT, 06269, United States

Keywords:
polyploidy
hybridization
phylogenomics
Funariaceae.

Presentation Type: Colloquium Presentations
Number: C7003
Abstract ID:766
Candidate for Awards:None