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PremiseThe genusAntennariahas a complex evolutionary history due to dioecism, excessive polyploidy, and the evolution of polyploid agamic complexes. We developed microsatellite markers fromA. corymbosato investigate genetic diversity and population genetic structure inAntennariaspecies. Methods and ResultsTwenty‐four novel microsatellite markers (16 nuclear and eight chloroplast) were developed fromA. corymbosausing an enriched genomic library. Ten polymorphic nuclear markers were used to characterize genetic variation in five populations ofA. corymbosa. One to four alleles were found per locus, and the expected heterozygosity and fixation index ranged from 0.00 to 0.675 and −0.033 to 0.610, respectively. We were also able to successfully amplify these markers in five additionalAntennariaspecies. ConclusionsThese markers are promising tools to study the population genetics of sexualAntennariaspecies and to investigate interspecific gene flow, clonal diversity, and parentage ofAntennariapolyploid agamic complexes.
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A novel synthesis of two decades of microsatellite studies on European beech reveals decreasing genetic diversity from glacial refugia
Abstract Genetic diversity influences the evolutionary potential of forest trees under changing environmental conditions, thus indirectly the ecosystem services that forests provide. European beech ( Fagus sylvatica L.) is a dominant European forest tree species that increasingly suffers from climate change-related die-back. Here, we conducted a systematic literature review of neutral genetic diversity in European beech and created a meta-data set of expected heterozygosity ( He ) from all past studies providing nuclear microsatellite data. We propose a novel approach, based on population genetic theory and a min–max scaling to make past studies comparable. Using a new microsatellite data set with unprecedented geographic coverage and various re-sampling schemes to mimic common sampling biases, we show the potential and limitations of the scaling approach. The scaled meta-dataset reveals the expected trend of decreasing genetic diversity from glacial refugia across the species range and also supports the hypothesis that different lineages met and admixed north of the European mountain ranges. As a result, we present a map of genetic diversity across the range of European beech which could help to identify seed source populations harboring greater diversity and guide sampling strategies for future genome-wide and functional investigations of genetic variation. Our approach illustrates how to combine information from several nuclear microsatellite data sets to describe patterns of genetic diversity extending beyond the geographic scale or mean number of loci used in each individual study, and thus is a proof-of-concept for synthesizing knowledge from existing studies also in other species.
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- Award ID(s):
- 2021898
- PAR ID:
- 10399723
- Date Published:
- Journal Name:
- Tree Genetics & Genomes
- Volume:
- 19
- Issue:
- 1
- ISSN:
- 1614-2942
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s11295-022-01577-4
