Sökning: "systematik"

Visar resultat 16 - 20 av 128 avhandlingar innehållade ordet systematik.

  1. 16. Evolution and biodiversity of the Ixoroideae (Rubiaceae)

    Författare :Kent Kainulainen; Birgitta Bremer; Sylvain Razafimandimbison; Torsten Eriksson; Sandra Knapp; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Alberteae; character evolution; classification; Condamineeae; fruit evolution; Ixoroideae; phylogenetics; pollen presentation; Rubiaceae; systematics; taxonomy; Systematics and phylogenetics; Systematik och fylogeni; växtsystematik; Plant Systematics;

    Sammanfattning : The phylogenetic relationships within subfamily Ixoroideae of the coffee family are investigated by phylogenetic reconstruction of molecular data, including regions of the chloroplast DNA (matK, ndhF, rbcL, rps16, trnH-psbA, trnS-G, and trnT-F), and the nuclear ribosomal DNA (ITS). The evolution of morphological characters within the group are inferred, with focus on characters used in classification. LÄS MER

  3. 17. Phylogeny and species delimitation in Roccellaceae and Physciaceae (Euascomycetes)

    Författare :Katileena Lohtander; Mats Wedin; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Systematics and phylogenetics; Systematik och fylogeni; systematisk botanik; Systematic Botany;

    Sammanfattning : DNA sequence data (the ITS region and Group I Introns) from the nuclear ribosomal repeat (rDNA), partial β-tubulin gene sequences, RAPD markers, and some morphological characters were analysed phylogenetically in order to examine relationships in lichenized Euascomycetes, from the species level to higher taxonomic levels. The species level studies comprise some so-called species pairs in two families, Roccellaceae (Arthoniales) and Physciaceae (Lecanorales). LÄS MER

  4. 18. Systematics and polyploid evolution in Potentilleae (Rosaceae)

    Författare :Magnus Lundberg; Torsten Eriksson; Jürg Schönenberger; Bengt Oxelman; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Potentilleae; Fragariinae; Potentilla; Sibbaldia; Fragaria; Alchemilla; systematics; phylogeny; polyploidy; autopolyploidy; allopolyploidy; reticulate evolution; Systematics and phylogenetics; Systematik och fylogeni; växtsystematik; Plant Systematics;

    Sammanfattning : This thesis comprises studies of the phylogenetic relationships in the flowering plant clade Potentilleae in Rosaceae. The relationships were elucidated by using DNA sequence data from the nuclear genome as well as from the plastid genome. In particular, the focus of the studies was the investigation of allopolyploidy, i.e. LÄS MER

  5. 19. Evolutionary relationships within the Lysimachia complex : with special emphasis on Anagallis

    Författare :Ulrika Manns; Arne A. Anderberg; Katarina Andreasen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Systematics and phylogenetics; Systematik och fylogeni; växtsystematik; Plant Systematics;

    Sammanfattning : This thesis focuses on Anagallis, an herbaceous genus with a distribution mainly in (sub-) tropical Africa, Madagascar or South America. A few species are found in drier climate. Anagallis is considered close to Lysimachia, separated based on mode of capsule dehiscence. LÄS MER

  7. 20. Phylogenetic Relationships of Silene sect. Melandrium and Allied Taxa (Caryophyllaceae), as Deduced from Multiple Gene Trees

    Författare :Anja Rautenberg; Bengt Oxelman; Mikael Thollesson; Magnus Lidén; Freek Bakker; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Silene; Elisanthe; Melandrium; Conoimorpha; Caryophyllaceae; Silene multinervia; relative dating; extreme substitution rates; phylogeny; BEST; BEAST; cpDNA; mtDNA; RNA polymerase; RPA2; RPB2; RPD2; SlX1; SlY1; ITS; introgression; incongruent phylogenies; chromosome count; coalescent; Bayes Factors; Systematics and phylogenetics; Systematik och fylogeni; systematisk botanik; Systematic Botany;

    Sammanfattning : This thesis focuses on phylogenetic relationships among some of the major lineages in Silene subgenus Behenantha (Caryophyllaceae) using DNA sequences from multiple, potentially unlinked gene regions from a large taxonomic and geographic sample. Both traditional phylogenetic analyses and a strategy to infer species trees and gene trees in a joint approach are used. LÄS MER