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  • 1. Blackmore, Stephen
    et al.
    Wortley, Alexandra H.
    Skvarla, John J.
    Gabarayeva, Nina I.
    Rowley, John R.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Developmental origins of structural diversity in pollen walls of Compositae2010Ingår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 284, nr 02-jan, s. 17-32Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    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.

  • 2. Eriksson, Torsten
    et al.
    Lundberg, Magnus
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Topel, Mats
    Östensson, Pia
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Smedmark, Jenny E. E.
    Sibbaldia: a molecular phylogenetic study of a remarkably polyphyletic genus in Rosaceae2015Ingår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 301, nr 1, s. 171-184Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    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.

  • 3.
    Hou, Chen
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Wikström, Niklas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik. Bergius Foundation, The Royal Academy of Sciences, Sweden.
    Strijk, Joeri S
    Rydin, Catarina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik. Bergius Foundation, The Royal Academy of Sciences, Sweden.
    Resolving phylogenetic relationships and species delimitations in closely related gymnosperms using high-throughput NGS, Sanger sequencing and morphology2016Ingår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 302, nr 9, s. 1345-1365Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    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.

  • 4. Kunze, H.
    et al.
    Wanntorp, L.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Corona and anther skirt in Hoya (Apocynaceae, Marsdenieae)2008Ingår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 271, nr 02-jan, s. 9-17Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    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.

  • 5.
    Löfstrand, Stefan D.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Razafimandimbison, Sylvain G.
    Rydin, Catarina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik. The Royal Swedish Academy of Sciences, Sweden.
    Phylogeny of Coussareeae (Rubioideae, Rubiaceae)2019Ingår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 305, nr 4, s. 293-304Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Coussareeae are a Neotropical clade of morphologically heterogeneous plants in the subfamily Rubioideae ofthe 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.

  • 6.
    Pornpongrungrueng, Pimwadee
    et al.
    Department of Biological Sciences, University of Aarhus.
    Borchsenius, Finn
    Department of Biological Sciences, University of Aarhus.
    Englund, Markus
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Anderberg, Arne A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Gustafsson, Mats H. G.
    Department of Biological Sciences, University of Aarhus.
    Phylogenetic relationships in Blumea (Asteraceae: Inuleae) as evidenced by molecular and morphological data2007Ingår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 269, s. 223-243Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    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.

  • 7.
    Rydin, Catarina
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen. Stockholms universitet, Naturvetenskapliga fakulteten, Bergianska botaniska trädgården (tills m Kungl. Vetenskapsakademien).
    Kainulainen, Kent
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen. Stockholms universitet, Naturvetenskapliga fakulteten, Bergianska botaniska trädgården (tills m Kungl. Vetenskapsakademien).
    Razafimandimbison, Sylvain
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen. Stockholms universitet, Naturvetenskapliga fakulteten, Bergianska botaniska trädgården (tills m Kungl. Vetenskapsakademien).
    Smedmark, Jenny
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen. Stockholms universitet, Naturvetenskapliga fakulteten, Bergianska botaniska trädgården (tills m Kungl. Vetenskapsakademien).
    Bremer, Birgitta
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen. Stockholms universitet, Naturvetenskapliga fakulteten, Bergianska botaniska trädgården (tills m Kungl. Vetenskapsakademien).
    Deep divergences in the coffee family and the systematic position of Acranthera2009Ingår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 278, s. 101-123Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    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.

  • 8.
    Rydin, Catarina
    et al.
    Swedish Museum of Natural History, Sweden.
    Wu, S. Q.
    Friis, E. M.
    Liaoxia Cao et SQ Wu (Gnetales): ephedroids from the Early Cretaceous Yixian Formation in Liaoning, northeastern China2006Ingår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 262, nr 3-4, s. 239-265Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    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.

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