Showing papers by "Elizabeth A. Zimmer published in 2016"
TL;DR: The sampling of the Vitales was expanded to include representatives of all major clades of the order, as well as representatives of other key lineages including Saxifragales, Dilleniales, and Santalales, and possible morphological synapomorphies shared between Vitales and Sax ifragales are discussed.
31 citations
TL;DR: It is suggested that geographic differentiation of this important invasive species has occurred more often within pathways that regulate growth and response to defense and stress, which may be associated with survival in North America's diverse climatic regions.
Abstract: Common ragweed (Ambrosia artemisiifolia L.) is an invasive, wind-pollinated plant nearly ubiquitous in disturbed sites in its eastern North American native range and present across growing portions of Europe, Africa, Asia, and Australia. Phenotypic divergence between European and native-range populations has been described as rapid evolution. However, a recent study demonstrated major human-mediated shifts in ragweed genetic structure before introduction to Europe and suggested that native-range genetic structure and local adaptation might fully explain accelerated growth and other invasive characteristics of introduced populations. Genomic differentiation that potentially influenced this structure has not yet been investigated, and it remains unclear whether substantial admixture during historical disturbance of the native range contributed to the development of invasiveness in introduced European ragweed populations. To investigate fine-scale population genetic structure across the species' native range, we characterized diallelic SNP loci via a reduced-representation genotyping-by-sequencing (GBS) approach. We corroborate phylogeographic domains previously discovered using traditional sequencing methods, while demonstrating increased power to resolve weak genetic structure in this highly admixed plant species. By identifying exome polymorphisms underlying genetic differentiation, we suggest that geographic differentiation of this important invasive species has occurred more often within pathways that regulate growth and response to defense and stress, which may be associated with survival in North America's diverse climatic regions.
24 citations
TL;DR: The microsatellite markers reported here provide a valuable tool for paternity analysis in S. stellata and will also be useful for investigating the population genetic structure and selection on floral design through male reproductive success of the North American native species.
Abstract: Premise of the study: We designed and tested microsatellite markers for the North American native species Silene stellata (Caryophyllaceae) to investigate its population genetic structure and identify selection on floral design through male reproductive success. Methods and Results: A total of 153 candidate microsatellite loci were isolated based on next-generation sequencing. We identified 18 polymorphic microsatellite loci in three populations of S. stellata, with di- or trinucleotide repeats. Genotyping results showed the number of alleles per locus ranged from six to 45 and expected heterozygosity ranged from 0.511 to 0.951. Five of these loci were successfully amplified in S. virginica and S. caroliniana and were also polymorphic. Conclusions: The microsatellite markers reported here provide a valuable tool for paternity analysis in S. stellata. They will also be useful for investigating the population genetic structures of S. stellata and related species.
4 citations