Global population genomics of Erigeron canadensis
"Erigeron canadensis L. (Asteraceae, syn. Conyza canadensis (L.) Cronquist) is an annual self-compatible herb with high selfing rate (96%) and high annual seed output. These weedy traits make E. canadensis a successful invader, and an economically significant agricultural weed, and as such, an important model species. The species is native to large parts of North America and has occupied a non-native range in large parts of the rest of the temperate and subtropical world. The diploid genome is very small (426 Mbp/1C).  E. canadensis seeds were sampled within the iCONNECT network (Lucas et al. 2024, doi:10.1007/s10530-024-03249-x) from 280 populations - 103 native and 177 non-native - widely distributed across the North Hemisphere. In a common garden experiment, we grew offspring from three mother plants per population. Fresh leaves were collected from one offspring per mother plant, dried in a freeze dryer, and conserved in silica gel until DNA extraction. Genomic DNA was extracted from the dry macerated leaves using the peqGOLD Plant DNA Mini Kit (Avantor ®).  We used a modified version of ddRADseq protocol of Peterson et al. (2012, doi:10.1371%2Fjournal.pone.0037135) to construct reduced-representation libraries of genomic DNA for the genotyping of single nucleotide polymorphisms (SNPs) as described in Durka et al. (2025, doi:10.1016/j.baae.2024.11.004). In short, approximately 200 ng of DNA from each sample was digested with EcoRI and MspI. Custom-barcoded adapters were then ligated to restriction fragments. Groups of 96 samples, each with unique barcodes, were pooled in equal volumes, purified with Promega-Wizard Gel and PCR Clean-up Kit, and size-selected using the Blue Pippin electrophoresis platform to select fragments of 350-450 bp in length. Unique external indices were added to each pool through PCR amplification. The PCR products were purified with the Promega Clean-up kit and AMPure XP beads. Fragment sizes were verified on an Agilent 2100 Bioanalyzer. Libraries were then pooled in equimolar quantities and sequenced using the Illumina NovaSeq™ 6000 Sequencing System using 10% PhiX. Demultiplexing of the raw reads was performed using process_radtags from the Stacks pipeline (Catchen et al. 2013, doi:10.1534/g3.111.000240). "
"Erigeron canadensis L. (Asteraceae, syn. Conyza canadensis (L.) Cronquist) is an annual self-compatible herb with high selfing rate (96%) and high annual seed output. These weedy traits make E. canadensis a successful invader, and an economically significant agricultural weed, and as such, an important model species. The species is native to large parts of North America and has occupied a non-native range in large parts of the rest of the temperate and subtropical world. The diploid genome is very small (426 Mbp/1C).  E. canadensis seeds were sampled within the iCONNECT network (Lucas et al. 2024, doi:10.1007/s10530-024-03249-x) from 280 populations - 103 native and 177 non-native - widely distributed across the North Hemisphere. In a common garden experiment, we grew offspring from three mother plants per population. Fresh leaves were collected from one offspring per mother plant, dried in a freeze dryer, and conserved in silica gel until DNA extraction. Genomic DNA was extracted from the dry macerated leaves using the peqGOLD Plant DNA Mini Kit (Avantor ®).  We used a modified version of ddRADseq protocol of Peterson et al. (2012, doi:10.1371%2Fjournal.pone.0037135) to construct reduced-representation libraries of genomic DNA for the genotyping of single nucleotide polymorphisms (SNPs) as described in Durka et al. (2025, doi:10.1016/j.baae.2024.11.004). In short, approximately 200 ng of DNA from each sample was digested with EcoRI and MspI. Custom-barcoded adapters were then ligated to restriction fragments. Groups of 96 samples, each with unique barcodes, were pooled in equal volumes, purified with Promega-Wizard Gel and PCR Clean-up Kit, and size-selected using the Blue Pippin electrophoresis platform to select fragments of 350-450 bp in length. Unique external indices were added to each pool through PCR amplification. The PCR products were purified with the Promega Clean-up kit and AMPure XP beads. Fragment sizes were verified on an Agilent 2100 Bioanalyzer. Libraries were then pooled in equimolar quantities and sequenced using the Illumina NovaSeq™ 6000 Sequencing System using 10% PhiX. Demultiplexing of the raw reads was performed using process_radtags from the Stacks pipeline (Catchen et al. 2013, doi:10.1534/g3.111.000240). "
HELMHOLTZ CENTRE FOR ENVIRONMENTAL RESEARCH - UFZ.