Abstract Detail

Pteridological Section/AFS

Metzgar, Jordan [1], Ickert-Bond, Stefanie [2].

Using next-generation DNA sequencing to explore the phylogeography of two species of parsley fern (Cryptogramma).

We generated next-generation sequence data for 40 populations of parsley fern from North America to characterize population-level genetic diversity and infer the location of refugia during the Last Glacial Maximum (LGM). 33 populations of the diploid Cryptogramma acrostichoides were included, as well as seven populations of the allotetraploid C. sitchensis. Sampled populations range from New Mexico to Alaska, with two to twenty individuals from each population. Previous research using plastid and nuclear DNA has identified C. acrostichoides as the maternal parent of C. sitchensis, with subsequent introgression from C. sitchensis into C. acrostichoides. DNA samples were pooled for each population and then underwent a double restriction enzyme digestion. Each pooled population was marked with a unique six basepair barcode. RADSeq (Restriction-site associated DNA sequencing) DNA sequence data were generated for each population using the Illumina HiSeq platform. Over 500 million sequence reads were generated for these populations. Following data processing and quality filtering, each population was represented by an average of 10 million sequencing reads. Putative loci had an average sequence coverage depth of 52.8 reads. We analyzed a SNP dataset using ploidy-aware distance clustering and mixture models selected with Bayesian information criterion scores to identify possible effects of algorithm selection. SNP data also revealed population structure and diversity through the use of population genetics statistics, phylogenetic analysis and Approximate Bayesian Computation (ABC). These patterns of genetic diversity identify putative refugia such as Beringia and the Pacific Northwest that served as recolonization sources for Cryptogramma following the LGM. Usage of cryptic refugia along the northern Pacific coast and isolated nunatak sites was assessed as a possible distinction in recolonization strategies between diploid and tetraploid taxa.

Broader Impacts:

1 - University of Alaska Fairbanks, Museum of The North, 907 Yukon Drive, Fairbanks, AK, 99775, USA
2 - University of Alaska Museum of The North, Herbarium (ALA) And Dept. of Biology And Wildlife, University of Alaska Fairbanks, 907 Yukon Dr., Fairbanks, AK, 99775, USA, 9074741510

Keywords:
Pteridaceae
RADSeq
Next-generation sequencing
Phylogeography
Cryptogramma.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Grand Salon A - D/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 5:30 PM
Number: PPD006
Abstract ID:864
Candidate for Awards:None