Limits...
Polyploidisation and geographic differentiation drive diversification in a European High Mountain Plant Group (Doronicum clusii Aggregate, Asteraceae).

Pachschwöll C, Escobar García P, Winkler M, Schneeweiss GM, Schönswetter P - PLoS ONE (2015)

Bottom Line: Taxonomic conclusions were informed, among others, by a Gaussian clustering method for species delimitation using dominant multilocus data.Doronicum glaciale subsp. calcareum was genetically and morphologically weakly separated from D. glaciale subsp. glaciale but exhibited significantly higher genetic diversity and rarity.This suggests that the more widespread D. glaciale subsp. glaciale originated from D. glaciale subsp. calcareum, which is restricted to a prominent Pleistocene refugium previously identified in other alpine plant species.

View Article: PubMed Central - PubMed

Affiliation: Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, A-1030 Vienna, Austria.

ABSTRACT
Range shifts (especially during the Pleistocene), polyploidisation and hybridization are major factors affecting high-mountain biodiversity. A good system to study their role in the European high mountains is the Doronicum clusii aggregate (Asteraceae), whose four taxa (D. clusii s.s., D. stiriacum, D. glaciale subsp. glaciale and D. glaciale subsp. calcareum) are differentiated geographically, ecologically (basiphilous versus silicicolous) and/or via their ploidy levels (diploid versus tetraploid). Here, we use DNA sequences (three plastid and one nuclear spacer) and AFLP fingerprinting data generated for 58 populations to infer phylogenetic relationships, origin of polyploids-whose ploidy level was confirmed by chromosomally calibrated DNA ploidy level estimates-and phylogeographic history. Taxonomic conclusions were informed, among others, by a Gaussian clustering method for species delimitation using dominant multilocus data. Based on molecular data we identified three lineages: (i) silicicolous diploid D. clusii s.s. in the Alps, (ii) silicicolous tetraploid D. stiriacum in the eastern Alps (outside the range of D. clusii s.s.) and the Carpathians and (iii) the basiphilous diploids D. glaciale subsp. glaciale (eastern Alps) and D. glaciale subsp. calcareum (northeastern Alps); each taxon was identified as distinct by the Gaussian clustering, but the separation of D. glaciale subsp. calcareum and D. glaciale subsp. glaciale was not stable, supporting their taxonomic treatment as subspecies. Carpathian and Alpine populations of D. stiriacum were genetically differentiated suggesting phases of vicariance, probably during the Pleistocene. The origin (autopolyploid versus allopolyploid) of D. stiriacum remained unclear. Doronicum glaciale subsp. calcareum was genetically and morphologically weakly separated from D. glaciale subsp. glaciale but exhibited significantly higher genetic diversity and rarity. This suggests that the more widespread D. glaciale subsp. glaciale originated from D. glaciale subsp. calcareum, which is restricted to a prominent Pleistocene refugium previously identified in other alpine plant species.

No MeSH data available.


Related in: MedlinePlus

Phylogenetic relationships of the Doronicum clusii aggregate based on nuclear DNA sequences.Maximum likelihood tree based on nuclear ITS data; numbers above branches are bootstrap support values above 50%. The coloured bar to the right represents morphologically defined taxa as in Fig. 1.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4352020&req=5

pone.0118197.g006: Phylogenetic relationships of the Doronicum clusii aggregate based on nuclear DNA sequences.Maximum likelihood tree based on nuclear ITS data; numbers above branches are bootstrap support values above 50%. The coloured bar to the right represents morphologically defined taxa as in Fig. 1.

Mentions: In the maximum likelihood tree of the 127 ITS sequences (-ln 2567.7; Fig. 6) the D. clusii aggregate forms a monophyletic group (BS 66). Doronicum clusii s.s., which shows no intraspecific sequence variation beyond a few ambiguous sites (Table 3), groups with cloned sequences of both D. × bauhini populations (BS 79). Doronicum stiriacum does not form a monophyletic group, but falls into two clades. An unsupported clade containing cloned sequences from the Carpathians (populations 36–38) and some, but not all populations from the Alps (populations 30–32, 35) is weakly supported sister (BS 56) to the unsupported clade containing D. glaciale subsp. calcareum, D. glaciale subsp. glaciale and D. stiriacum. Sequences of D. stiriacum (from all populations) form a clade (BS 63) sister group to a clade (BS 55) comprising D. glaciale subsp. calcareum, D. glaciale subsp. glaciale, their morphological intermediates and cloned sequences of both D. × bauhini populations. Samples from D. glaciale subsp. calcareum, D. glaciale subsp. glaciale and their morphological intermediates intermix, and phylogenetic structure, if present, does not correspond to taxonomic boundaries.


Polyploidisation and geographic differentiation drive diversification in a European High Mountain Plant Group (Doronicum clusii Aggregate, Asteraceae).

Pachschwöll C, Escobar García P, Winkler M, Schneeweiss GM, Schönswetter P - PLoS ONE (2015)

Phylogenetic relationships of the Doronicum clusii aggregate based on nuclear DNA sequences.Maximum likelihood tree based on nuclear ITS data; numbers above branches are bootstrap support values above 50%. The coloured bar to the right represents morphologically defined taxa as in Fig. 1.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4352020&req=5

pone.0118197.g006: Phylogenetic relationships of the Doronicum clusii aggregate based on nuclear DNA sequences.Maximum likelihood tree based on nuclear ITS data; numbers above branches are bootstrap support values above 50%. The coloured bar to the right represents morphologically defined taxa as in Fig. 1.
Mentions: In the maximum likelihood tree of the 127 ITS sequences (-ln 2567.7; Fig. 6) the D. clusii aggregate forms a monophyletic group (BS 66). Doronicum clusii s.s., which shows no intraspecific sequence variation beyond a few ambiguous sites (Table 3), groups with cloned sequences of both D. × bauhini populations (BS 79). Doronicum stiriacum does not form a monophyletic group, but falls into two clades. An unsupported clade containing cloned sequences from the Carpathians (populations 36–38) and some, but not all populations from the Alps (populations 30–32, 35) is weakly supported sister (BS 56) to the unsupported clade containing D. glaciale subsp. calcareum, D. glaciale subsp. glaciale and D. stiriacum. Sequences of D. stiriacum (from all populations) form a clade (BS 63) sister group to a clade (BS 55) comprising D. glaciale subsp. calcareum, D. glaciale subsp. glaciale, their morphological intermediates and cloned sequences of both D. × bauhini populations. Samples from D. glaciale subsp. calcareum, D. glaciale subsp. glaciale and their morphological intermediates intermix, and phylogenetic structure, if present, does not correspond to taxonomic boundaries.

Bottom Line: Taxonomic conclusions were informed, among others, by a Gaussian clustering method for species delimitation using dominant multilocus data.Doronicum glaciale subsp. calcareum was genetically and morphologically weakly separated from D. glaciale subsp. glaciale but exhibited significantly higher genetic diversity and rarity.This suggests that the more widespread D. glaciale subsp. glaciale originated from D. glaciale subsp. calcareum, which is restricted to a prominent Pleistocene refugium previously identified in other alpine plant species.

View Article: PubMed Central - PubMed

Affiliation: Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, A-1030 Vienna, Austria.

ABSTRACT
Range shifts (especially during the Pleistocene), polyploidisation and hybridization are major factors affecting high-mountain biodiversity. A good system to study their role in the European high mountains is the Doronicum clusii aggregate (Asteraceae), whose four taxa (D. clusii s.s., D. stiriacum, D. glaciale subsp. glaciale and D. glaciale subsp. calcareum) are differentiated geographically, ecologically (basiphilous versus silicicolous) and/or via their ploidy levels (diploid versus tetraploid). Here, we use DNA sequences (three plastid and one nuclear spacer) and AFLP fingerprinting data generated for 58 populations to infer phylogenetic relationships, origin of polyploids-whose ploidy level was confirmed by chromosomally calibrated DNA ploidy level estimates-and phylogeographic history. Taxonomic conclusions were informed, among others, by a Gaussian clustering method for species delimitation using dominant multilocus data. Based on molecular data we identified three lineages: (i) silicicolous diploid D. clusii s.s. in the Alps, (ii) silicicolous tetraploid D. stiriacum in the eastern Alps (outside the range of D. clusii s.s.) and the Carpathians and (iii) the basiphilous diploids D. glaciale subsp. glaciale (eastern Alps) and D. glaciale subsp. calcareum (northeastern Alps); each taxon was identified as distinct by the Gaussian clustering, but the separation of D. glaciale subsp. calcareum and D. glaciale subsp. glaciale was not stable, supporting their taxonomic treatment as subspecies. Carpathian and Alpine populations of D. stiriacum were genetically differentiated suggesting phases of vicariance, probably during the Pleistocene. The origin (autopolyploid versus allopolyploid) of D. stiriacum remained unclear. Doronicum glaciale subsp. calcareum was genetically and morphologically weakly separated from D. glaciale subsp. glaciale but exhibited significantly higher genetic diversity and rarity. This suggests that the more widespread D. glaciale subsp. glaciale originated from D. glaciale subsp. calcareum, which is restricted to a prominent Pleistocene refugium previously identified in other alpine plant species.

No MeSH data available.


Related in: MedlinePlus