Using genomics to guide seed-sourcing at the right taxonomical level for ecological restoration projects: the complex case of Carex bigelowii s.lat. in Norway

• Main Authors: Westergaard, Kristine Bakke, Kyrkjeeide, Magni Olsen, Brandrud, Marie Kristine
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2022
• Subjects: double-digest restriction site-associated DNA sequencing (ddRAD-seq); Carex bigelowii
• Online Access: https://doi.org/10.5061/dryad.4b8gthtdr

There is a growing demand for ecological restoration using suitable seeds following international standards or national legal demands for local seed-sourcing. However, before selecting the appropriate geographic origin of seeds, it is vital to explore taxonomic complexity related to the focal taxa. We used ddRAD-seq to screen genomic diversity within Carex bigelowii s.lat. focussing on Norway. This species complex is considered a candidate for seeding, but presents considerable morphological, ecological, and genetic variation. The genetic structure of 132 individuals of C . bigelowii s.lat., including C . nigra as an outgroup, was explored using ordinations, clustering analyses, and a genetic barrier algorithm. Two highly divergent clusters were evident, supporting the recognition of two taxonomic units ' C . dacica ' and 'subsp. bigelowii '. Previously defined seed-sourcing regions for C . bigelowii s.lat. did not consider the known taxonomic complexity, and therefore interpreted the overall genetic structure as seed-sourcing regions, not taxa. We estimated genetic neighbourhood sizes within each taxon to be 100-150 km and 300 km, respectively, indicating species-specific delimitations of local seed-sourcing regions. Frequent hybrids, local genetic distinctiveness, and suggested ecotypes add complexity to the discussed seed-sourcing regions. Our results show how genomic screening of diversity and structure in a species complex can alleviate the taxonomic impediment, inform practical questions and legal requirements related to seed-sourcing, and together with traditional taxonomic work provide necessary information for a sound management of biodiversity. Uploaded file "Pop_vs_Sample_vs_CollectorsID" lists the pop_ID, Sample_ID_vcf and the Voucher_ID for all samples. pop_ID is the site number as listed in Table 1 in the publication. Sample_ID_vcf is the individual sample ID as used in the dataset files A and B Voucher_ID is the individual herbarium/DNA-collection identification for each samples, also listed in ...