1. |
|
|
2. |
- Bella, Eleni, et al.
(author)
-
Genetic insights into the hybrid origin of Abies x borisii-regis Mattf.
- 2015
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110 .- 2199-6881. ; 301:2, s. 749-759
-
Journal article (peer-reviewed)abstract
- Abies × borisii-regis Mattf. (King Boris fir) is a taxon endemic to the southern Balkan Peninsula, described as a hybrid between the widespread A. alba Mill. (Silver fir) and the Greek endemic A. cephalonica Loud (Greek fir). Even though A. × borisii-regis has attracted much research attention in the past, its origin, geographical distribution and taxonomic status are not fully elucidated and molecular evidence for hybridization is missing. To shed more light on this issue, we analyzed representative populations from these three Abies taxa using paternally inherited (chloroplast) and maternally inherited (mitochondrial) DNA markers. Both Silver and Greek fir could be clearly distinguished using mitochondrial markers, while we observed a mixture of maternal lineages in theA. × borisii-regis populations. In contrast, using chloroplast markers, we could not identify species-specific haplotypes, but a neighbor-joining analysis of population genetic distances revealed two separate clusters for the Silver fir and the Greek fir, while the A. × borisii-regis populations were placed in intermediate positions. Our results are in agreement with the hypothesis that the A. ×borisii-regis populations investigated are a result of hybridization between A. cephalonica and A. alba.
|
|
3. |
- Bengtson, Annika, et al.
(author)
-
Species diversification in the Mediterranean genus Chiliadenus (Inuleae-Asteraceae)
- 2018
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110 .- 2199-6881. ; 304:7, s. 853-860
-
Journal article (peer-reviewed)abstract
- Chiliadenus is a small genus in the Inuleae (Asteraceae), consisting of ten species with allopatric distributions along the southern edge of the Mediterranean Sea. The different species have restricted areas of distribution, with only one being more widely distributed. The first molecular phylogenetic study of the genus with complete sampling, as well as a biogeographic analysis of the origin and biogeographic patterns leading to the current diversity of Chiliadenus is presented. Results confirm Chiliadenus as monophyletic and placed as sister to Dittrichia. The ancestor of Chiliadenus is dated to have diverged from that of Dittrichia around 5.45 Ma ago, coinciding with the Messinian salinity crisis, whereas the Chiliadenus crown group is dated to 2.29 Ma, around 3 million years later. Ancestral area reconstructions show the crown group to likely have originated in the area around Morocco and northwestern Algeria, which is also the area where the early divergences have occurred. Chiliadenus has then later diverged and dispersed over the Mediterranean to its current distribution. The evolution of the Chiliadenus crown group coincides with the onset of the Mediterranean climate, and its evolution may be connected to the subsequent climatic changes.
|
|
4. |
- Blackmore, Stephen, et al.
(author)
-
Developmental origins of structural diversity in pollen walls of Compositae
- 2010
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 284:02-jan, s. 17-32
-
Journal article (peer-reviewed)abstract
- Compositae exhibit some of the most complex and diverse pollen grains in flowering plants. This paper reviews the evolutionary and developmental origins of this diversity in pollen structure using recent models based on the behaviour of colloids and formation of micelles in the differentiating microspore glycocalyx and primexine. The developmental model is consistent with observations of structures recovered by pollen wall dissolution. Pollen wall diversity in Compositae is inferred to result from small changes in the glycocalyx, for example ionic concentration, which trigger the self-assembly of highly diverse structures. Whilst the fine details of exine substructure are, therefore, not under direct genetic control, it is likely that genes establish differences in the glycocalyx which define the conditions for self-assembly. Because the processes described here for Compositae can account for some of the most complex exine structures known, it is likely that they also operate in pollen walls with much simpler organisation.
|
|
5. |
- Cronberg, Nils, et al.
(author)
-
Hybridization between the peat mosses, Sphagnum capillifolium and S. quinquefarium (Sphagnaceae, Bryophyta) as inferred by morphological characters and isozyme markers
- 2002
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 234:1-4, s. 53-70
-
Journal article (peer-reviewed)abstract
- Isozyme markers and morphological characters were studied in four populations of Sphagnum capillifolium and S. quinquefarium. Recombinant plants were found in three populations, where the two species occur sympatrically. All recombinants possessed different haplotypes and combinations of morphological characters, which show that they are results of independent hybridization events. Strongly male-biased sex ratios were found for Sphagnum capillifolium in all populations where it grew sympatrically with S. quinquefarium. Most of the recombinants were also male fertile. These observations suggest that S. quinquefarium is the female parent in the primary crosses and in subsequent backcrosses.
|
|
6. |
- Dawes, T., et al.
(author)
-
Extremely low genetic diversity in the European clade of the modelbryophyte Anthoceros agrestis
- 2020
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110 .- 2199-6881. ; 306:2
-
Journal article (peer-reviewed)abstract
- The hornwort Anthoceros agrestis is emerging as a model system for the study of symbiotic interactions and carbon fixation processes. It is an annual species with a remarkably small and compact genome. Single accessions of the plant have been shown to be related to the cosmopolitan perennial hornwort Anthoceros punctatus. We provide the first detailed insight into the evolutionary history of the two species. Due to the rather conserved nature of organellar loci, we sequenced multiple accessions in the Anthoceros agrestis–A. punctatus complex using three nuclear regions: the ribosomal spacer ITS2, and exon and intron regions from the single-copy coding genes rbcS and phytochrome. We used phylogenetic and dating analyses to uncover the relationships between these two taxa. Our analyses resolve a lineage of genetically near-uniform European A. agrestis accessions and two non-European A. agrestis lineages. In addition, the cosmopolitan species Anthoceros punctatus forms two lineages, one of mostly European accessions, and another from India. All studied European A. agrestis accessions have a single origin, radiated relatively recently (less than 1 million years ago), and are currently strictly associated with agroecosystem habitats.
|
|
7. |
- Dida, Mulatu Geleta, et al.
(author)
-
Phylogenetics and taxonomic delimitation of the genus Guizotia (Asteraceae) based on sequences derived from various chloroplast DNA regions
- 2010
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 289, s. 77-89
-
Journal article (peer-reviewed)abstract
- Parsimony-based phylogenetic analyses of the genus Guizotia were undertaken based on DNA sequence data from the following chloroplast DNA (cpDNA) regions: trnT-trnL, trnL-trnF, trnY-rpoB, trnC-petN, psbM-trnD and rps16-trnQ intergenic spacers, trnL, rps16 and matK-5'trnK introns and matK gene. Out of the 26 primers used in this study, 14 were newly designed. The study was conducted to determine (1) the closest relative of Guizotia abyssinica, (2) the taxonomic status of some Guizotia taxa and (3) the subtribal placement of Guizotia in the tribe Heliantheae. The analyses of the sequence data showed that G. abyssinica, G. scabra ssp. scabra, G. scabra ssp. schimperi and G. villosa are phylogenetically closely related. However, G. scabra ssp. schimperi appeared as the most closely related taxon to G. abyssinica. Based on this phylogenetic analysis, we suggest that the two subspecies of G. scabra are better treated as separate species. The analysis also clearly demonstrated that "Chelelu" and "Ketcha" are distinct Guizotia species. The trnT-trnL and trnL-trnF intergenic spacer-based phylogenetic analysis of various subtribes of the tribe Heliantheae strongly supports the placement of the genus Guizotia within the subtribe Milleriinae.
|
|
8. |
- Ehlers, B. K., et al.
(author)
-
Floral morphology and reproductive success in the orchid Epipactis helleborine : regional and local across-habitat variation
- 2002
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 236:1-2, s. 19-32
-
Journal article (peer-reviewed)abstract
- The terrestrial orchid Epipactis helleborine is a morphologically variable species with a wide distribution in Europe. It is pollinated by social wasps, and most populations show the morphological characteristics of outcrossing species. However, local predominantly selfing subspecies and varieties have been documented from drier habitats. To document geographic variation in floral morphology, ability to produce seeds through autogamy, and reproductive success in E. helleborine, we sampled 13 populations from three geographic regions along a latitudinal gradient of c. 1000 km from northern to southern Sweden. In the southernmost region, populations in dry and mesic habitats were compared. Supplemental hand-pollination was conducted to determine whether among-population variation in fruit set could be explained by differences in the natural level of pollination, and whether any relationship between floral morphology and fruit production could be explained by interactions with pollinators. Bagging experiments showed no evidence of autogamy in any of the study populations. Number of flowers, pollinia removal and fruit set varied significantly among populations but did not differ among regions. Pollinia removal was positively correlated with population size and both pollinia removal and fruit set were lower in dry than in mesic habitats. At the level of the individual plant, the number of pollinia removed increased more rapidly with flower number than did number of fruits produced. The hand-pollination experiment indicated that the positive relationship between number of flowers and fruit production was due to a higher degree of pollen limitation in plants with few flowers than in plants with many flowers. The experiment also showed that variation in the level of pollen limitation could only partly explain variation in fruit set among populations.
|
|
9. |
- Eriksson, T., et al.
(author)
-
Sibbaldia: a molecular phylogenetic study of a remarkably polyphyletic genus in Rosaceae
- 2015
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 2199-6881 .- 1615-6110. ; 301:1, s. 171-184
-
Journal article (peer-reviewed)abstract
- Using DNA sequence data from nuclear ribosomal ITS in combination with plastid trnLF spacer and trnL intron data, we show that Sibbaldia is a polyphyletic assemblage. It falls into five separate clades of Potentilleae, three within Fragariinae and two within Potentilla (Potentillinae sensu Sojak). To a large extent, our results are congruent with Sojak's findings based on morphological characters such as anther structure. Four of the Sibbaldia species included in this study remain in Sibbaldia, while S. adpressa is classified in Sibbaldianthe, S. perpusilloides is considered to represent a new genus in Fragariinae, Chamaecallis Smedmark, S. micropetala is nested within the Potentilla anserina clade, and four species belong to a basal clade of Potentilla. The phylogenetic affinity of Sibbaldiopsis is still unsettled, but one of the three species that have been classified in the genus is found to belong inside Sibbaldia, and it should be named Sibbaldia retusa (O.F. Muller) T. Erikss. Further study will show whether the remaining two species, Potentilla cuneifolia and P. miyabei, are more closely related to Sibbaldia, Sibbaldianthe, or if they make up a distinct lineage separate from either of these.
|
|
10. |
|
|
11. |
- Ferm, Julia
(author)
-
A preliminary phylogeny of Zapoteca (Fabaceae: Caesalpinioideae: Mimosoid clade)
- 2019
-
In: Plant Systematics and Evolution. - : SPRINGER WIEN. - 0378-2697 .- 1615-6110 .- 2199-6881. ; 305:5, s. 341-352
-
Journal article (peer-reviewed)abstract
- The legume genus Zapoteca is separated from the genus Calliandra, i.e., by having pollen arranged in 16-grained polyads (compared to 8-grained polyads in Calliandra) and in chromosome number (13 vs. 8 or 11). As currently circumscribed, Zapoteca contains 22 species and 13 subspecies placed in five subgenera. This study included 20 species and 11 subspecies representing all subgenera. Representative species from the closely related genera Calliandra, Havardia, Pithecellobium and Viguieranthus were also included, as the more distantly related species Senegalia senegal and Vachellia farnesiana. The aims of this study were to test the monophyly of Zapoteca and investigate phylogenetic relationships within the genus. Total DNA was extracted from leaf material and the nuclear ETS and ITS, and plastid trnL-trnF regions were amplified. Additional sequence data were downloaded from GenBank, and the data sets were analyzed using Bayesian inference. Results show that Zapoteca is monophyletic and that the monospecific subgenera (subg. Nervosa and subg. Aculeata) are resolved as separate lineages within the genus, subg. Nervosa (containing Z. nervosa) as sister to all remaining taxa of Zapoteca. Subgenera containing more than one species (subg. Amazonica, subg. Zapoteca and subg. Ravenia) are shown to be non-monophyletic. Two subspecies of Z. caracasana, subsp. caracasana and subsp. weberbaueri, are found together in a clade. Furthermore, Zapoteca tehuana and Z. portoricensis subsp. portoricensis, Z. formosa subsp. gracilis and Z. formosa subsp. schottii are shown to be monophyletic. However, the other subspecific taxa of Z. formosa and of Z. portoricensis are not supported as monophyletic.
|
|
12. |
- Fiz-Palacios, Omar, et al.
(author)
-
Imbalanced diversification of two Mediterranean sister genera (Bellis and Bellium, Asteraceae) within the same time frame
- 2011
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 295:1-4, s. 109-118
-
Journal article (peer-reviewed)abstract
- The Daisies, Bellis and Bellium, form a monophyletic complex within the core Astereae (Asteraceae). Although most early diverging lineages show an African distribution, the core Astereae is today widespread on five continents with the Bellis/Bellium complex as the only representative in the Mediterranean basin. Molecular clock estimates placed the divergence of Astereae from its sister tribe Anthemideae in the Oligocene. Using a combination of three plastid genes, we estimated divergence times for different lineages of the tribe Astereae. This, together with temporal and biogeographical reconstructions using the nrITS region, allows placing and timing of the major lineages of the Bellis/Bellium complex. The age reconstruction places the divergence of the tribe Astereae in the late Miocene (18-19 million years ago), followed by an out-of-Africa dispersal into Asia where the worldwide expansion may have started. Our results suggest that the colonization of the Mediterranean basin by the Astereae started from Eurasia some 10 million years ago. A Messinian early divergence of the Bellis/Bellium complex in the Mediterranean was estimated. However, a parallel 4-million-year delay for the within-genera diversification was inferred, probably related to the establishment of the sclerophyllous Mediterranean forest. Despite a similar time frame for the within-genera diversification, today's species numbers differ considerably between Bellis (15 spp.) and Bellium (five spp.).
|
|
13. |
- Freire, Susana E., et al.
(author)
-
The Lucilia group (Asteraceae, Gnaphalieae): phylogenetic and taxonomic considerations based on molecular and morphological evidence.
- 2015
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110 .- 2199-6881. ; 301, s. 1227-1248
-
Journal article (peer-reviewed)abstract
- The Lucilia group sensu Anderberg and Freire comprises nine South American genera: Belloa, Berroa, Chevreulia, Cuatrecasasiella, Facelis, Gamochaetopsis, Jalcophila, Lucilia and Luciliocline. The aims of this contribution were, using DNA sequences from plastid (rpl32-trnL, trnL-F) and nuclear (ITS and ETS) markers, together with morphological characters, to test the monophyly of the Lucilia group and provide new insight into generic circumscriptions. Our studies, including a broad taxon sampling of Gnaphalieae species, suggest that the Lucilia group is paraphyletic, since Antennaria, Chionolaena, Gamochaeta, Loricaria, Micropsis, Mniodes and Stuckertiella are all nested within the Lucilia group. Morphology and molecular analyses combined showed that the traditional generic circumscription of most of the genera (e.g., Berroa, Chevreulia, Chionolaena, Cuatrecasasiella, Facelis, Jalcophila and Micropsis) correlates with the inferred phylogenetic relationships. Conversely, Lucilia and Luciliocline are non-monophyletic. Lucilia is nested in a clade with Berroa, Facelis and Micropsis. Luciliocline is strongly embedded within the clade Belloa pp + Mniodes. Our results are consistent with Dillon’s study that considered Belloa as a montotypic genus (B. chilensis). Luciliocline and the remaining species of Belloa are accommodated in the genus Mniodes, and the necessary combinations are proposed for the expanded Mniodes. All the analyses showed that the monotypic genera Stuckertiella and Gamochaetopsis are in a well-supported clade nested within Gamochaeta, which implies that taxonomic changes are required also for these genera. Internal relationships in the group and the key morphological characters used in the taxonomy of the group, as well as incongruences found between morphological and molecular analyses, are discussed.
|
|
14. |
- FRIIS, Else Marie, et al.
(author)
-
Notonuphar antarctica, an extinct water lily (Nymphaeales) from the Eocene of Antarctica
- 2017
-
In: Plant Systematics and Evolution. - Vienna : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110 .- 2199-6881. ; 303:7, s. 969-980
-
Journal article (peer-reviewed)abstract
- A new genus and species, Notonuphar antarctica, is described from the Eocene of Seymour (Marambio) Island, the Antarctic Peninsula and assigned to the Nymphaeales based on well-preserved seeds. This is the first record of a water lily from Antarctica and the first record of a Gondwanan plant with close link to the genus Nuphar (Nymphaeaceae), which is restricted today to the Northern Hemisphere. Critical features for systematic placement of Notonuphar are the presence of a germination cap with closely spaced hilar scar and micropyle, anatropous, bitegmic and exotestal seed organization, exotesta composed of one cell layer of high sclerenchymatic palisade-shape cells, mesotesta of smaller, low parenchymatic cells, a few cell layers deep, and a thin tegmen. The seeds of Notonuphar are particularly similar to seeds of extant and fossil Nuphar in the straight, unfolded anticlinal wall of the exotestal cells and the presence of a narrow zone of exotestal tissue between hilum and micropyle. Other seed features including the very tall exotestal cells and strongly thickened cell walls of exotesta also link Notonuphar to Brasenia and related fossil taxa (Cabombaceae). This character mosaic observed in Notonuphar corroborates the transitional position of Nuphar between Cabombaceae and Nymphaeaceae. Notonuphar is the only member of Nymphaeales recorded from Antarctica and so far the only fossil seeds of Nymphaeales known from the Southern Hemisphere. The discovery of this extinct Gondwanan taxon with features suggesting close relationship with extant Northern Hemisphere genus Nuphar is a further evidence for the relictual nature of the extant group.
|
|
15. |
|
|
16. |
- Groppo, Milton, et al.
(author)
-
Placement of Kuhlmanniodendron Fiaschi & Groppo in Lindackerieae (Achariaceae, Malpighiales) confirmed by analyses of rbcL sequences, with notes on pollen morphology and wood anatomy
- 2010
-
In: PLANT SYSTEMATICS AND EVOLUTION. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 286:1-2, s. 27-37
-
Journal article (peer-reviewed)abstract
- The phylogenetic placement of Kuhlmanniodendron Fiaschi & Groppo (Achariaceae) within Malpighiales was investigated with rbcL sequence data. This genus was recently created to accommodate Carpotroche apterocarpa Kuhlm., a poorly known species from the rainforests of Espirito Santo, Brazil. One rbcL sequence was obtained from Kuhlmanniodendron and analyzed with 73 additional sequences from Malpighiales, and 8 from two closer orders, Oxalidales and Celastrales, all of which were available at Genbank. Phylogenetic analyses were carried out with maximum parsimony and Bayesian inference; bootstrap analyses were used in maximum parsimony to evaluate branch support. The results confirmed the placement of Kuhlmanniodendron together with Camptostylus, Lindackeria, Xylotheca, and Caloncoba in a strongly supported clade (posterior probability = 0.99) that corresponds with the tribe Lindackerieae of Achariaceae (Malpighiales). Kuhlmanniodendron also does not appear to be closely related to Oncoba (Salicaceae), an African genus with similar floral and fruit morphology that has been traditionally placed among cyanogenic Flacourtiaceae (now Achariaceae). A picrosodic paper test was performed in herbarium dry leaves, and the presence of cyanogenic glycosides, a class of compounds usually found in Achariaceae, was detected. Pollen morphology and wood anatomy of Kuhlmanniodendron were also investigated, but both pollen (3-colporate and microreticulate) and wood, with solitary to multiple vessels, scalariform perforation plates and other features, do not seem to be useful to distinguish this genus from other members of the Achariaceae and are rather common among the eudicotyledons as a whole. However, perforated ray cells with scalariform plates, an uncommon wood character, present in Kuhlmanniodendron are similar to those found in Kiggelaria africana (Pangieae, Achariaceae), but the occurrence of such cells is not mapped among the angiosperms, and it is not clear how homoplastic this character could be.
|
|
17. |
- GUSTAFSSON, L, et al.
(author)
-
LOW GENETIC-VARIATION IN SWEDISH POPULATIONS OF THE RARE SPECIES VICIA-PISIFORMIS (FABACEAE) REVEALED WITH RFLP (RDNA) AND RAPD
- 1994
-
In: Plant Systematics and Evolution. - 0378-2697 .- 1615-6110. ; 189:3-4, s. 133-148
-
Journal article (peer-reviewed)abstract
- Nine Swedish populations, 1-5 individuals/population, and one cultivated individual of the rare species Vicia pisiformis were investigated for genetic variation. In hybridizations with two rDNA probes using 8 restriction enzymes, only two individuals belonging to one population were polymorphic. A map of the rDNA gene cluster was constructed for four of the restriction enzymes used. Two of the polymorphic sites were mapped and were found to be located outside regions coding for rRNA, presumably caused by single point mutations or small deletions. The repeat length of the rDNA region was c. 10,000 bp, which corresponds well with the size found for other species belonging to Fabaceae. No length polymorphism was found in the intergenic spacer, contrary to the situation found for most other plant species investigated for rDNA variation. The haplotype diversity for the species (Hsp Shannon) was very low (0.055). Within-population values (Hpop) was 0 for all populations except the variable one, which had 0.301. PCR amplification with 6 random primers also revealed very low levels of genetic diversity. A polymorphism was observed in a limited number of individuals for four populations. Hsp was 0.065 and HpopBAR was 0.050. The average D value (Wetton) for the PCR haplotypes was 0.99.
|
|
18. |
|
|
19. |
|
|
20. |
|
|
21. |
|
|
22. |
- Hedren, Mikael
(author)
-
Spatial genetic structure in the Madeiran endemic Dactylorhiza foliosa (Orchidaceae)
- 2022
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 308:4
-
Journal article (peer-reviewed)abstract
- Oceanic islands have isolated biota, which typically include many endemic species. However, island endemics are vulnerable due to small population sizes, and they are often threatened by habitat destruction or by introduced pests and predators. Adequate conservation planning requires good information on genetic variability and population structure, also when seemingly viable species are considered. Here, I analysed the genetic structure in the terrestrial orchid Dactylorhiza foliosa, which is endemic to Madeira. This species is a characteristic component of evergreen laurel forests occupying the northern slopes of the island. Levels of diversity in both the plastid genome and in the nuclear genome were comparable to levels of diversity found in congeners growing in continental regions. Within populations, plants separated by distances up to 256 m shared plastid haplotypes significantly more often than plants at random, but when nuclear markers were considered, only plants growing closer than eight metres were significantly more closely related. Analysis of plastid marker variation revealed that gene dispersal by seeds is not sufficiently large to counterbalance the accumulation of mutations that build up divergence between the most distant populations. However, differentiation in the nuclear genome was considerably smaller, suggesting that gene dispersal by pollen is much more efficient than gene dispersal by seeds in D. foliosa. The overall pollen to seed dispersal ratio, mp/ms, was 7.30. Considering genetic parameters, conditions for long-term persistence of D. foliosa on Madeira seem to be good.
|
|
23. |
- Hedrén, Mikael
(author)
-
Systematics of the Dactylorhiza euxina/incarnata/maculata polyploid complex (Orchidaceae) in Turkey: evidence from allozyme data
- 2001
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 229:1-2, s. 23-44
-
Journal article (peer-reviewed)abstract
- Material of Dactylorhiza were sampled from 49 localities in Turkey and investigated for allozyme variation at ten loci (nine enzyme systems). Among diploids, the Anatolian D. osmanica and D. umbrosa were allozymically variable, but not distinct from each other or from D. incarnata. Dactylorhiza saccifera contained the same alleles as the European D. fuchsii. Dactylorhiza iberica and D. euxina were distinct from each other and the other diploids. On basis of allozyme patterns three distinct allotetraploid genotypes were distinguished, and each of them could be treated as a separate species. Dactylorhiza nieschalkiorum is similar to European allotetraploids, and may have arisen from hybridization between D. incarnata s.l. and D. saccifera. Dactylorhiza urvilleana may have arisen from parents related to present-day D. saccifera and D. euxina, but it also contains additional alleles that have not been found in any of the diploids investigated. A third allotetraploid known from four populations in the Ardahan and Kars provinces of north-eastern Turkey combines the allozyme patterns found in material of D. incarnata s.l. from the same area with those from D. euxina. It is here described for the first time as D. armeniaca.
|
|
24. |
- Hou, Chen, et al.
(author)
-
Resolving phylogenetic relationships and species delimitations in closely related gymnosperms using high-throughput NGS, Sanger sequencing and morphology
- 2016
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110 .- 2199-6881. ; 302:9, s. 1345-1365
-
Journal article (peer-reviewed)abstract
- Plastid genomes have been widely applied to elucidate plant evolution at higher taxonomic levels, but have rarely been considered useful for addressing close relationships. Here, we resolve the phylogeny and taxonomy of the Chinese lianoid Gnetum clade (Gnetales), using high throughput and Sanger sequencing techniques and studies of plant morphology. Despite previous efforts, relationships among taxa and the taxonomy within the clade have remained unclear. We generated 11 plastid genomes representing one arborescent and four lianoid species. Phylogenetic analyses were conducted using (a) the entire plastid genomes and (b) the protein-coding genes only. Sequence divergence among the lianoid species was substantial, with 9345 variable sites. Four variable regions were identified, targeted and sequenced for an additional 54 specimens and analyzed together with one nuclear ribosomal marker. Results from the phylogenetic analyses corroborate G. parvifolium as sister to the remaining lianoid species and support the presence of at least five additional species in the Chinese lianoid clade: G. catasphaericum, G. formosum, G. luofuense, G. montanum and G. pendulum. Following morphological investigations, G. giganteum and G. gracilipes are included in and synonymized with G. pendulum. Gnetum hainanense is included in and synonymized with G. luofuense. Two names, G. indicum and G. cleistostachyum, remain questionable. A taxonomic revision and a key to Chinese lianoid Gnetum are presented. Internal nodes in the Chinese lianoid Gnetum clade are from the Miocene and onwards and coincide with the expansion of tropical to subtropical forests in South China, which may have facilitated speciation in the clade.
|
|
25. |
- Jacobson, Anders, et al.
(author)
-
Phylogenetic relationships in Alisma (Alismataceae) based on RAPDs, and sequence data from ITS and trnL
- 2007
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 265:1-2, s. 27-44
-
Journal article (peer-reviewed)abstract
- The phylogeny of Alisma (Alismataceae), a genus of approximately nine species of aquatic plants mainly distributed in the Northern Hemisphere, was reconstructed with parsimony analysis on RAPD data and sequences of the nuclear ITS and chloroplast trnL regions, and with MDS on RAPD data. Separate analyses were performed on each data set. Butomus umbellatus was used as outgroup in the analysis of sequence data, and Luronium and Baldellia in the analyses of RAPD data. Among diploid Alisma, two major groups were found: (i) the gramineum group consisting of A. gramineum and A. wahlenbergii, and (ii) the plantago-aquatica group with A. plantago-aquatica, A. orientale, A. subcordatum, A. juzepczukii and A. "bottnicum". Taxa within the groups were poorly separated. The Baltic endemics A. wahlenbergii, A. juzepczukii and A. "bottnicum" have probably originated relatively recently from local populations of A. gramineum (i.e. A. wahlenbergii) and A. plantago-aquatica (i.e. A. juzepczukii and A. "bottnicum"). The exact origin of the polyploid taxa, i.e. A. lanceolatum, A. triviale, A. canaliculatum and A. rariflorum, is still unclear.
|
|
26. |
- Kunze, H., et al.
(author)
-
Corona and anther skirt in Hoya (Apocynaceae, Marsdenieae)
- 2008
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 271:02-jan, s. 9-17
-
Journal article (peer-reviewed)abstract
- The so called revolute margins of the corona in the genus Hoya (Marsdenieae) are homologous to the anther skirt. The anther skirt is primarily formed of two latero-basal lobes of the anther. In Hoya these lobes are fused with the underside of the basal process of the staminal corona and have evolved into a dominant structure of the gynostegium. Embedded in the anther skirt is the nectar tube, formed by the basal elongation of the guide rail. In many species, however, the function of nectar secretion for pollinator reward has been transferred to the anther skirt beneath the basal process of the corona. A survey of the Marsdenieae shows that the potential for developing an anther skirt is present in several other genera as well, though nowhere has it evolved into such elaborated structures as in Hoya.
|
|
27. |
|
|
28. |
- Loots, Sonja, et al.
(author)
-
Genetic variation among and within Lithops species in Namibia
- 2019
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110 .- 2199-6881.
-
Journal article (peer-reviewed)abstract
- The dwarf succulent genus Lithops is endemic to Southern Africa and of considerable conservation concern. Species delimitation is often problematic and based mainly on leaf morphology, which is strongly associated with habitat. Relationships between taxa and populations in Namibia were studied with amplified fragment length polymorphisms using 44 wild Lithops populations representing 15 species and 23 taxa. Four primer pairs produced 92 polymorphic bands in the 223 samples. Expected heterozygosity (H-e) within taxa ranged from 0.086 to 0.450. Genetic and geographic distances were correlated according to a Mantel test. Analysis of molecular variance showed only 23% variation among the 15 investigated species. Genetic differentiation and structuring were investigated with a principal coordinate analysis, a neighbour-joining and a Bayesian phylogeny, a Bayesian clustering analysis and a discriminant analysis of principal components. In all five analyses, L. optica and L. herrei, which differ only in flower colour, clustered closely together and are here combined under L. optica. The morphologically similar species L. amicorum and L. karasmontana clustered together. Lithops amicorum is therefore reduced to subspecific level: L. karasmontana subsp. amicorum, comb. nov. Subspecific taxa overlapped to a large extent except in L. karasmontana where 13% of the variability resided among subspecies, whereas the nominal subspecies differed from subsp. bella and subsp. eberlanzii; the latter two could not be separated and are here combined under L. karasmontana subsp. bella.
|
|
29. |
- Långström, Elisabeth, et al.
(author)
-
Tribes of Boraginoideae (Boraginaceae) and placement of Antiphytum , Echiochilon , Ogastemma and Sericostoma : A phylogenetic analysis based on atp B plastid DNA sequence data
- 2002
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 234:1-4, s. 137-153
-
Journal article (peer-reviewed)abstract
- The genera Antiphytum, Echiochilon, Ogastemma and Sericostoma, which have been difficult to place within the tribes of the subfamily Boraginoideae (Boraginaceae), are analysed using plastid atpB sequence data. A selection of Boraginaceae genera was used to obtain a framework for the phylogenetic position of Antiphytum, Echiochilon, Ogastemma and Sericostoma. Sericostoma is found to belong within Echiochilon. The new tribe Echiochileae, Boragineae and Lithospermeae are monophyletic but the tribes Eritrichieae and Cynoglosseae are paraphyletic. The biogeography of Echiochileae (Echiochilon and Ogastemma from Africa and western Asia, and Antiphytum from America) is discussed.
|
|
30. |
- Löfstrand, Stefan, et al.
(author)
-
Phylogeny of Coussareeae (Rubioideae, Rubiaceae)
- 2019
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 2199-6881 .- 1615-6110. ; 305, s. 293-304
-
Journal article (peer-reviewed)abstract
- Coussareeae are a Neotropical clade of morphologically heterogeneous plants in the subfamily Rubioideae of the coffee family (Rubiaceae). The tribe encompasses about 330 species assigned to ten genera: Bradea, Coccocypselum, Coussarea, Cruckshanksia, Declieuxia, Faramea, Heterophyllaea, Hindsia, Oreopolus, and Standleya. Historically, the genera of Coussareeae have rarely been considered closely related, and the widely defined Coussareeae were delimited based on molecular systematics without proposed morphological synapomorphies. In order to assess the tribe’s monophyly, as well as the generic limits, infrageneric relationships, and suprageneric relationships, multiple specimens per genus were sampled whenever possible and analyzed using multiple molecular loci with the Bayesian and maximum likelihood methods. The results of the phylogenetic analyses (all genera represented by multiple terminals are monophyletic, all genera are resolved with respect to each other, and three major suprageneric clades are resolved), coupled with herbarium and literature studies, were used to identify potential synapomorphic features. Non-molecular diagnostic features remain elusive for Coussareeae as a whole, but we have identified multiple diagnostic features and potential synapomorphies for each of the three major suprageneric clades: (1) Coussarea and Faramea(e.g., porate pollen grains with annuli bordering the pores); (2) Bradea, Coccocypselum, Declieuxia, Hindsia, and Standleya (e.g., colporate pollen grains with complex reticulate tecta); and 3) Cruckshanksia, Heterophyllaea, and Oreopolus (e.g., chartaceous, loculicidal capsules). The latter clade, distributed in different biomes of the Andes, is sister to the former two, both widely distributed in the Neotropics.
|
|
31. |
- Malm, J U, et al.
(author)
-
Chloroplast DNA haplotypes in Nordic Silene dioica: postglacial immigration from the east and the south
- 2005
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 250:1-2, s. 27-38
-
Journal article (peer-reviewed)abstract
- Analysis of PCR/RFLP variation in 57 Nordic populations of the herb Silene dioica, revealed 13 composite chloroplast DNA (cpDNA) haplotypes. The geographic distribution of the haplotypes suggests that the postglacial colonization of Fennoscandia by S. dioica may have involved immigration of populations from two main directions. The commonest cpDNA haplotype dominates in populations throughout most of Finland and northern and central Sweden, but is absent from southern Sweden. The distribution of this haplotype is interpreted in terms of immigration from an eastern or northern direction. In contrast, eight haplotypes that are absent from northern Fennoscandia are represented in populations in southern Sweden and in Denmark, suggesting colonization by populations derived from one or several refugial areas further to the south in Europe. The overall NE-SW pattern of cpDNA haplotype variation is similar to, but less diffuse than, the pattern revealed by allozyme markers.
|
|
32. |
- Marcussen, Thomas, 1971, et al.
(author)
-
Species delimitation in the Ponto-Caucasian Viola sieheana complex, based on evidence from allozymes, morphology, ploidy levels, and crossing experiments
- 2011
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 291:3-4, s. 183-196
-
Journal article (peer-reviewed)abstract
- Information from allozymes, ploidy levels, morphology, cross-compatibility and biogeography suggests that the easternmost occurrences of the Ponto-Caucasian Viola sieheana should be considered to belong to a separate species, V. caspia. Morphological characters delimitating V. sieheana and V. caspia are presented and discussed. The main distribution of V. sieheana s. str. is in the eastern Balkans, Turkey, Cyprus, and The Lebanon, and of V. caspia in the Caspio-Caucasian region westwards to Crimea and north-eastern Turkey. Their distributions in the intermediate areas remain unknown. Plants of V. sieheana s. str. from Cyprus, Greece, and Turkey were all blue-flowered and had the chromosome number 2n = 12x = 60. Its presence in the Peloponnese (Parnon, TaAgetos, Menalon) and in the Pindhos mountains, Greece, was confirmed. Reports of plants with 2n = 8x = 40 from these stations seem to refer to the sterile hybrid V. reichenbachiana x sieheana which is locally abundant. V. caspia from Azerbaijan had 2n = 8x = 40 and had either whitish or blue flowers. In spite of sympatry and almost complete cross-compatibility, the two corolla colour morphs showed strong allozymic differentiation in four out of seven isozyme systems, suggesting reproductive isolation and incipient speciation. Within section Viola, V. caspia and V. sieheana seem no more closely related to each other than to either of the other investigated European species. The possibility that V. sieheana is an ancient allopolyploid involving the Greek narrow endemic V. dirphya (2n = 40) is discussed.
|
|
33. |
- Meseguer, Andrea, et al.
(author)
-
Utility of low-copy nuclear markers in phylogenetic reconstruction of Hypericum L. (Hypericaceae)
- 2014
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 300:6, s. 1503-1514
-
Journal article (peer-reviewed)abstract
- Primers and sequence variation for two low-copy nuclear genes (LCG) not previously used for phylogenetic inference in the genus Hypericum, PHYC and EMB2765, are presented here in comparison with the fast-evolving nuclear intergenic spacer ITS. Substitution rates in the LCG markers were half those reported in ITS for Hypericum, which might help avoid the problems caused by substitution saturation and difficulties to establish homologies that afflict the latter marker. We included representatives of all major clades within Hypericum and found that levels of phylogenetic resolution, clade support values and internal character consistency were similar to, or even higher than, those of ITS-based phylogenies. The presence of at least two copies in EMB2765 in Hypericum imposed a methodological challenge that was circumvented by the design of an effective clade-specific primer. Both EMB2765 and, especially, PHYC appear to be good alternatives to the ITS marker, confirming the main phylogenetic relationships found in previous studies, but with improved resolution and support values for some basal relationships.
|
|
34. |
- Morrison, David
(author)
-
A framework for phylogenetic sequence alignment
- 2009
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 282, s. 127-149
-
Research review (peer-reviewed)
|
|
35. |
- Oh, Il-Chan, et al.
(author)
-
Comparative seed morphology and character evolution in the genus Lysimachia (Myrsinaceae) and related taxa
- 2008
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 271:3-4, s. 177-197
-
Journal article (peer-reviewed)abstract
- We investigated seed morphology in 34 species of the genus Lysimachia and in 14 species and two subspecies of six additional genera (Anagallis, Ardisiandra, Asterolinon, Glaux, Pelletiera, Trientalis), which have been shown to be closely related to, or are placed within Lysimachia in previous molecular studies. We studied seed shape, seed coat structure, and seed coat surface patterns. Three major types of seed shape were identified: (1) sectoroid, (2) polyhedral, and (3) coarsely rugose with concave hilar area. In addition, seeds may be keeled or winged. The outer layer of the seed coat is either sponge-like and adhering only loosely to the inner seed coat or it is thin and tightly adhering to the underlying tissue. Seed surface patterns can be divided into six main types: (1) reticulate, (2) tuberculate, (3) vesiculose, (4) colliculate, (5) undulate, or (6) poroid-alveolate. Seed surface patterns are mostly congruent with molecular phylogenetic relationships. A reticulate surface pattern is diagnostic of, e.g. Lysimachia subgenera Palladia and Hawaiian Lysimachiopsis. Mapping seed characters onto a recent phylogenetic tree, reveals that they provide potentially synapomorphic character states for various subclades of Lysimachia. Salient examples include a rugose seed shape, which turns out to be synapomorphic for the clade comprising the genus Pelletiera plus Asterolinon linum-stellatum and a sponge-like outer seed coat layer, which characterizes a clade with Lysimachia vulgaris, L. thyrsiflora, and L. terrestris, with an analogue that apparently evolved in parallel in Trientalis europaea. We also discuss possible habitat factors that may have favored the independent evolution of particular seed types such as winged seeds in various lineages.
|
|
36. |
- Olofsson, Sofie, et al.
(author)
-
Genetic differentiation and postglacial migration of the Dactylorhiza majalis ssp traunsteineri/lapponica complex into Fennoscandia
- 2008
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 276:1-2, s. 73-87
-
Journal article (peer-reviewed)abstract
- Eight variable regions (microsatellites, insertion/deletion and duplication regions) from the plastid DNA genome were analyzed for 91 populations belonging to Dactylorhiza majalis ssp. traunsteineri and closely related taxa. A total of 36 composite plastid haplotypes were found. The two dominating haplotypes had a clear geographic distribution suggesting at least two separate immigration routes into Scandinavia after the last glaciation: one southwestern route and one or two southeastern routes. D. majalis ssp. traunsteineri could not be clearly separated from any of the other taxa included in the study except for D. majalis ssp. sphagnicola. The morphologically similar taxa D. majalis ssp. traunsteineri, D. majalis ssp. lapponica and D. majalis ssp. russowii showed no genetic differentiation, and therefore we suggest an amalgamation of the three taxa into one broadly circumscribed subspecies; D. majalis ssp. lapponica. The plastid data also revealed incidents of hybridization and possible introgression between D. majalis ssp. lapponica and other members of the genus, e.g., D. incarnata.
|
|
37. |
- Ordas, Jorge Anton D., et al.
(author)
-
Phylogeny and the evolutionary origins of myrmecophytism in the Neonauclea clade (Rubiaceae) revisited, with particular emphasis on the Philippine lineages
- 2021
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 307:3
-
Journal article (peer-reviewed)abstract
- The Australasian Neonauclea is the largest genus of the tribe Naucleeae (subfamily Cinchonoideae, Rubiaceae) and is well known for its extensive radiation of myrmecophytic species. The genus is paraphyletic with respect to the genera Ludekia and Myrmeconauclea, and these three genera constitute the Neonauclea clade sensu Löfstrand et al. The Philippines is a center of species diversity of Neonauclea; however, its members have yet to be included in any molecular studies. We produced a phylogeny of the Neonauclea clade based on sequence data from nuclear (ETS and ITS) and plastid (rbcL and trnT-F) markers and including a large sampling of Neonauclea species from the Philippines. The resulting phylogeny was used to assess the phylogenetic positions and relationships of the Philippine Neonauclea species within the Neonauclea clade. We also reassessed the origins of myrmecophytism in the Neonauclea clade using ancestral state reconstructions. The sampled Philippine Neonauclea were resolved in five morphologically and geographically distinct clades. Our ancestral state reconstructions inferred a non-myrmecophytic ancestor for the Neonauclea clade, as shown by Razafimandimbison et al., and suggested at least two independent origins of myrmecophytism, one in myrmecophytic Myrmeconauclea and another in the myrmecophytic Neonauclea species from core Neonauclea. Losses of myrmedomes through multiple evolutionary reversals back to the non-myrmedome condition were inferred within core Neonauclea. Unlike the Bornean myrmecophytic lineages, our results favored a single origin of the Philippine endemic myrmecophytic Neonauclea.
|
|
38. |
- Persson, Helena, et al.
(author)
-
Allozyme diversity and genetic structure of marginal and central populations of Corylus avellana L. (Betulaceae) in Europe
- 2004
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 244:3-4, s. 157-179
-
Journal article (peer-reviewed)abstract
- Corylus avellana L. (hazel, Betulaceae) is a long-lived, widespread shrub in Europe, having its northern range margin in Fennoscandia and a postglacial history involving range-expansion from refugial areas in southern Europe. In this study, we tested for a relationship between marginality and low within-population genetic diversity by assessing patterns of variation at 14 putatively neutral allozyme loci (comprising 43 putative alleles) within and between 40 natural populations of C. avellana along a north-south transect in Europe. Geographically marginal populations (central Sweden) showed lower levels of within-population diversity than populations in more central regions, as indicated by significant negative correlations between latitude and the percentage of polymorphic loci (r(S)=-0.47, P < 0.001), the average number of alleles per locus (r(S)=-0.65, P < 0.001), the expected heterozygosity (r(S)=-0.19, P < 0.05), and the proportion of distinguishable genotypes (r(S)=-0.56, P < 0.001). These patterns, combined with the unusually high between-population component of gene diversity (G(ST)=19.7%) and allelic richness (A(ST)=24%) in the marginal region, can be attributed to historical bottlenecks during the species' postglacial range-expansion, but may also reflect a history of genetic drift in the small, isolated populations occupying the marginal region. Information on the spatial distribution of genotypes provide further support for a role of vegetative reproduction (layering) in the structuring of genetic variation within populations.
|
|
39. |
- Pornpongrungrueng, Pimwadee, et al.
(author)
-
Phylogenetic relationships in Blumea (Asteraceae: Inuleae) as evidenced by molecular and morphological data
- 2007
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 269, s. 223-243
-
Journal article (peer-reviewed)abstract
- The present study, based on sequences of cpDNA (trnL-F & psbA-trnH) and nrDNA (ITS) and morphology, examined the evolutionary relationships in Blumea and its position among related genera. The results confirmed that the closest relatives of Blumea are Caesulia, Duhaldea and Pentanema p.p., and showed that the monotypic genera Blumeopsis and Merrittia are nested within Blumea. In Blumea s.l., two major, well-supported clades were recognised and a single species, the widespread Blumea balsamifera, that could not be placed with certainty relative to the two main clades. The two main clades differ in habit, ecology and distribution. The Blumea densiflora clade contains shrubs and subshrubs of evergreen forests, distributed from continental Asia to New Guinea and Polynesia, whereas the Blumea lacera clade is a widespread paleotropical group that comprises mostly annual, weedy herbs of open forests and fields.
|
|
40. |
- Potter, Daniel, et al.
(author)
-
Phylogeny and classification of Rosaceae
- 2007
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 266, s. 5-43
-
Journal article (peer-reviewed)
|
|
41. |
- Prentice, Honor C, et al.
(author)
-
Chloroplast DNA variation in the European herb Silene dioica (red campion): postglacial migration and interspecific introgression
- 2008
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 272:1-4, s. 23-37
-
Journal article (peer-reviewed)abstract
- Many recent studies of intraspecific geographic variation in maternally inherited chloroplast DNA (cpDNA) in European trees have revealed haplotype distributions that can be interpreted in terms of scenarios of postglacial migration and range expansion. However, there is still a lack of comparable information from widespread herb species. In the present study, we investigated the geographic distribution of cpDNA variation in 124 populations, covering a large part of the range of the widespread, dioecious, European herb, Silene dioica. PCR-RFLP analysis revealed 24 different cpDNA haplotypes. As in the majority of European tree species, the large-scale geographic distributions of the most common S. dioica haplotypes suggest that the species colonized Europe from more than one geographic source. Material from 16 populations of S. latifolia and five hybrid populations was also included in the study for comparative purposes. Five out of seven haplotypes detected in S. latifolia were shared with S. dioica. The similarity of the geographic distributions of the shared haplotypes in both species is consistent with a history of past and/or recent interspecific hybridization and introgression between these closely related plants. The two haplotypes detected only in S. latifolia were present in populations in the Mediterranean region – on the southern margin of the species’ area of sympatry, or outside the range of S. dioica.
|
|
42. |
- Ronse De Craene, Louis, et al.
(author)
-
Flower morphology and anatomy of Sabia (Sabiaceae): structural basis of an advanced pollination system among basal eudicots
- 2015
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110 .- 2199-6881. ; 301:6, s. 1543-1553
-
Journal article (peer-reviewed)abstract
- Flowers of four species of Sabia are investigated using scanning electron and light microscopy to understand the complex floral system of Sabiaceae and to contribute to the understanding of the systematic position of the family among early diverging eudicots. The structure of the mature flower and the floral anatomy are here described and compared with that of the sister genus Meliosma. The floral structure is relatively uniform with the greatest variability in the shape of the nectary and the differentiation of the style. Flowers share a similar pollen release mechanism, as pollen is extruded from the monosporangiate thecae through an inward-out dehiscence process leading to seemingly extrorse anthers occasionally accompanied by the curving of the upper part of the filaments. The bicarpellate ovary is divided in a synascidiate zone and a symplicate zone of similar size with two superposed unitegmic ovules per carpel. The floral Bauplan of Sabia can be interpreted as precursory to a further evolution of the monosymmetric flower of Meliosma, as both genera share numerous characters. The isolated position of Sabiaceae in the early diverging eudicots is highlighted by their unique floral morphology, although several features point to a link with Ranunculales, such as Menispermaceae. These probably reflect the existence of apomorphic tendencies shared by members of the early diverging eudicots.
|
|
43. |
- Rosquist, Gabrielle, et al.
(author)
-
Genetic variation in Scandinavian Anthericum liliago (Anthericaceae): allopolyploidy, hybridization and immigration history
- 2002
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 236:1-2, s. 55-72
-
Journal article (peer-reviewed)abstract
- We investigated patterns of isozyme variation and the hierarchic structure of genetic diversity in 25 Scandinavian populations of the lilioid herb, Anthericum liliago. Isozyme data suggest that tetraploid A. liliago has an allopolyploid origin and that A. ramosum may be one of its diploid progenitors. Two populations contained known or suspected hybrids between A. liliago and A. ramosum. Isozymes show that one population from S Sweden contains both triploid (hybrid) and tetraploid individuals whereas a putatively hybrid Danish population represents diploid A. liliago. There is an overall northward and eastward decline in allelic richness in the tetraploid populations, with the highest numbers of alleles in Denmark and SW Sweden. This pattern is consistent with a progressive loss of allelic variation during the species' postglacial colonization of Scandinavia. The between-population component of genetic diversity is 4% (compared with 12% in diploid A. ramosum), the between-region diversity component is 7% and 89% of the total diversity is stored within populations.
|
|
44. |
- Rydin, Catarina, et al.
(author)
-
Deep divergences in the coffee family and the systematic position of Acranthera
- 2009
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 278, s. 101-123
-
Journal article (peer-reviewed)abstract
- Despite extensive efforts, there are unresolved questions on evolutionary relationships in the angiosperm family Rubiaceae. Here, information from six loci and 149 Rubiaceae taxa provide new insights. Acranthera and Coptosapelta are strongly supported as sisters. Pollen grains of Acranthera possess several features common in Rubiaceae, but amongst potential similarities with the unusual grains of Coptosapelta are the nature of the apertures andthe structure of the sexine. Luculia, Acranthera and Coptosapelta are excluded from the three subfamilies Ixoroideae, Cinchonoideae and Rubioideae. Sipaneeae and Condamineeae form a clade, sister to remaining Ixoroideae. Rondeletieae and Guettardeae are sisters to remaining Cinchonoideae. Colletoecema is sister to remaining Rubioideae, followed by the Urophylleae–Ophiorrhizeae clade. Nuclear ITS provided structured information at all phylogenetic levels, but the main gain from adding nrITS was the increased resolution. Average support values also increased but were generally high also without nrITS andthe increase was not statistically significant.
|
|
45. |
- Rydin, Catarina, et al.
(author)
-
Liaoxia Cao et SQ Wu (Gnetales) : ephedroids from the Early Cretaceous Yixian Formation in Liaoning, northeastern China
- 2006
-
In: Plant Systematics and Evolution. - 0378-2697 .- 1615-6110. ; 262:3-4, s. 239-265
-
Journal article (peer-reviewed)abstract
- Gnetalean compression-impression fossils are described from the Early Cretaceous Yixian Formation, Liaoning Province, north-eastern China, and assigned to six species of Liaoxia Cao et S.Q. Wu. The fossils have opposite-decussate phyllotaxis and cones comprising 2–12 pairs of bracts. Ovulate cones have seeds typically in a distal position. The species differ from each other and from previously described fossils in the absence or presence of leaves, shape of cones and seeds, and shape and position of cone bracts. The species of Liaoxia are probably close relatives of extant species of Ephedra L., but diagnostic reproductive details that could confirm this hypothesis are not preserved. The restricted information in the fossils and the poorly understood morphological diversity of extant Ephedra, prevent assignment of the fossils to any particular subgroup of Ephedra, as well as an explicit exclusion of them from the extant genus.
|
|
46. |
- Salomon, Björn
(author)
-
The origin of the H, St, W, and Y genomes in allotetraploid species of Elymus L. and Stenostachys Turcz. (Poaceae: Triticeae)
- 2011
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110. ; 291, s. 197-210
-
Journal article (peer-reviewed)abstract
- Based on sequences from two single-copy nuclear genes (DMC1 and EF-G), four plastid genes (rbcL, rpoA, matK, and ndhF), and one mitochondrial gene (coxII), we investigate the origin of the H, St, W, and Y genomes in four allotetraploid species of Elymus and two allotetraploid species of Stenostachys. Despite significant incongruence between the two nuclear genes and between the nuclear and organelle data partitions, individual and combined analyses of the data partitions unequivocally show that the St and H genomes of the tetraploid American species of Elymus are derived from Pseudoroegneria and Hordeum, respectively, with Pseudoroegneria serving as the female parent, and that the H and W genomes of Stenostachys are derived from Hordeum and Australopyrum, respectively, with Hordeum serving as the female parent. The analyses equally clearly demonstrate that the St genome of the tetraploid Asiatic Elymus species is derived from Pseudoroegneria, with the latter serving as the female parent, but the relationship of the Y genome is less clear. Individual analyses of the nuclear genes provide conflicting results, but combined analysis of all data suggests a sister group relationship to Heteranthelium, albeit without any jackknife support.
|
|
47. |
- Snogerup, Sven, et al.
(author)
-
Changes in the flora of some Aegean islets 1968-2000
- 2004
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 245:3-4, s. 169-213
-
Journal article (peer-reviewed)abstract
- The flora of 17 islets was studied during the period 1968-2000, with thorough inventories from 1971. At each visit the species present and their population sizes were noted. The flora of the smallest islets of hard rock consisted mainly of perennials, and remained unchanged in terms of species present throughout the period of study. In the larger and more complex islets the major part of the flora consisted of islet-specialised taxa staying for long periods of time. To them are added some other mostly casual species from the close large islands, introduced by human influence, birds or winds and standing for most of the turnover in the islets' flora. Few changes were observed in the plant communities of rock crevices, the spray zone of the shores and other constant habitats. The dominant perennial species forming layer of shrubs or subshrubs also mostly remained the same. Most of the changes concerned soil spaces opened by animals or erosion. Most annual species were found to survive by an extreme seed bank strategy. Many taxa common on the neighbouring islands were lacking or casual on the islets. Some others reached dominance or high frequencies that have not been observed on islands or in mainland areas. The conditions for the flora on the Aegean islets are considered to differ fundamentally from that on large isolated islands because they are situated comparatively close among each other and to islands and mainland areas. They are also vulnerable towards catastrophic events and therefore frequently presenting opened targets for invasions. The islet-specialised taxa are found to retain good ability for dispersal over moderately long distances. The grazing of the islets is stated to be an important factor for the evolution of islet adapted and specialised taxa.
|
|
48. |
- Soubani, Eman, et al.
(author)
-
Genetic and morphological differentiation across a contact zone between two postglacial immigration lineages of Helianthemum nummularium (Cistaceae) in southern Scandinavia
- 2015
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697 .- 2199-6881. ; 301:5, s. 1499-1508
-
Journal article (peer-reviewed)abstract
- Helianthemum nummularium (L.) Mill. has two subspecies in southern Scandinavia, which differ in an indumentum character that is inherited as a Mendelian gene with two alleles. The dominant allele is the genetic basis for the key character of subsp. obscurum (absence of a dense felt of stellate hairs on the abaxial surface of the leaf), whereas the recessive allele is the genetic basis for the key character of subsp. nummularium (presence of a dense felt of stellate hairs). Subsp. obscurum occurs in southwest Scandinavia, whereas subsp. nummularium occurs in southeast Scandinavia. The distributions of the two subspecies overlap in a wide zone in south Sweden, where natural populations consist of a mixture of the two subspecies in various proportions. Eighty-five percent of the investigated populations in this zone are polymorphic. A significant positive correlation exists between latitude/longitude across the zone and the frequency of the recessive indumentum allele. There is no significant difference in the leaf shape between the two subspecies, but there is a geographical trend across the zone. Twenty-seven populations displayed six plastid DNA haplotypes in Scandinavia. The geographic distribution of four of these haplotypes supports an eastern postglacial immigration lineage, whereas the distribution of two others haplotypes supports a postglacial immigration lineage from southwest.
|
|
49. |
- Sousa, Filipe de, 1982, et al.
(author)
-
Patterns of phylogenetic incongruence in Medicago found among six linkage groups
- 2016
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 0378-2697 .- 1615-6110 .- 2199-6881. ; 302:5, s. 493-513
-
Journal article (peer-reviewed)abstract
- The species phylogeny of Medicago L. (Leguminosae) remains unresolved, as there is significant incongruence between the published gene phylogenies. Here, we compare six of these gene phylogenies of Medicago, inferred from unlinked loci from the nuclear, chloroplast and mitochondrial genomes. Data from all loci were re-analysed, including gap-coding of initial data sets, and dated phylogenies were produced. The patterns of species relationships observed in the six dated phylogenies are compatible with several different biological processes, such as incomplete lineage sorting and hybridisation. A subset of the original sampling that included 29 taxa was also analysed using coalescent-based tree distance comparisons. The observed topological distances suggest that differences between gene phylogenies cannot be solely attributed to incomplete lineage sorting. Hybridisation is strongly suspected to have occurred in the history of many taxa in the genus, because of overlapping divergence times between suspected hybrids and each parental lineage, confirming earlier results based on only two genes. An attempt to reconcile the conflicting histories in a multispecies coalescent analysis, using multiple labels for taxa with hybrid histories, did not produce satisfactory results and may be fatally limited. We conclude that although the currently available data are not sufficient to clarify relationships in Medicago, many cases of hybridisation are probable. The phylogenetic history of the genus is therefore better understood as a network and not a single tree. This raises concerns over previous studies that have used single gene trees as summaries of the history of species relationships.
|
|
50. |
- Ståhlberg, David, et al.
(author)
-
Systematics and phylogeography of the Dactylorhiza maculata complex (Orchidaceae) in Scandinavia: insights from cytological, morphological and molecular data
- 2008
-
In: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 273:1-2, s. 107-132
-
Journal article (peer-reviewed)abstract
- Flow cytometry, morphometry and molecular markers [plastid DNA and internal transcribed spacers(ITS) of nuclear ribosomal DNA] were used to determine taxonomic and phylogeographic patterns in Dactylorhiza maculata s.l. from Scandinavia. A total of 238 individuals from 27 populations from throughout all of Scandinavia, including the adjacent Kola Peninsula of Russia, were analyzed. Diploid D. maculata ssp. fuchsii and autotetraploid D. maculata ssp. maculata are morphologically differentiated. Fragment size variants from 10 plastid DNA loci (seven microsatellite loci and three loci with indel variation) were combined to give 43 haplotypes. Three major groups of haplotypes were found. Group I haplotypes were prevalent in the north and the northeast, whereas Group II haplotypes were prevalent in the south and the southwest. Group III was represented by only a single haplotype and appeared to be the result of introgression from D. incarnata s.l. Group I and Group II haplotypes did not correspond with cytologically and morphologically defined D. maculata ssp. fuchsii or D. maculata ssp. maculata. Past introgressive gene flow rather than recent hybridization is envisaged. Intermediate Group I haplotypes between Group II and the rest of Group I were detected in a zone of contact in central Sweden, which may suggest plastid DNA recombination. The six ITS alleles scored showed strong positive correlation with taxonomy. All data sets obtained for ssp. maculata were significantly correlated with geography. Three different autotetraploid lineages are hypothesized. One lineage may represent postglacial immigration from the south and the other two lineages may represent eastern immigration routes. Morphology and ITS data suggested that subarctic populations of ssp. maculata should be recognized as var. kolaensis.
|
|