Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2013
Abstract
The relative frequency of Therrya fuckelii and T. pini fruiting on dead branches of Scots pine was investigated in southern Norway by examining lightning-damaged and wind-fallen trees, randomly collected branches and Nordic herbarium collections of these ascomycetes representing the order Rhytismatales. Ascus, ascospore, and subhymenium characteristics were used as criteria for species identification, while a sequence analysis of ITS rDNA gene cluster was performed to compare the relatedness of the species to each other and to corresponding fungal sequences available at the NCBI GenBank Sequence Database. In a few cases, the two Therrya species co-occurred on the same branch, but in general, whether field or herbarium material, T. fuckelii was clearly more common than T. pini.Within the Nordic countries, both species occurred throughout the natural distribution area of Scots pine. The ITS rDNA sequence of T. pini strains was 91% similar to T. fuckelii strains, the differences locating both within the internal transcribed spacers ITS1 and ITS2 and the 5.8 S rDNA gene. More variation in the ITS1-5.8S-ITS2 sequence was observed among T. pini than T. fuckelii samples; genetic implications of this finding are discussed. Upon sequence analysis, we discovered that a T. pini sequence has been deposited in the NCBI GenBank under a false identity. We emphasize the importance of co-examining strains that originate from mature fruit bodies with fully developed morphologic features as reference samples.
Authors
Hanne Sogge Thomas Rohrlack Trine Ballestad Rounge Jørn Henrik Sønstebø Ave Tooming-Klunderud Tom Kristensen Kjetill Sigurd JakobsenAbstract
Several Planktothrix strains, each producing a distinct oligopeptide profile, have been shown to coexist within Lake Steinsfjorden (Norway). Using nonribosomal peptide synthetase (NRPS) genes as markers, it has been shown that the Planktothrix community comprises distinct genetic variants displaying differences in bloom dynamics, suggesting a Planktothrix subpopulation structure. Here, we investigate the Planktothrix variants inhabiting four lakes in southeast of Norway utilizing both NRPS and non-NRPS genes. Phylogenetic analyses showed similar topologies for both NRPS and non-NRPS genes, and the lakes appear to have similar structuring of Planktothrix genetic variants. The structure of distinct variants was also supported by very low genetic diversity within variants compared to the between-variant diversity. Incongruent topologies and split decomposition revealed recombination events between Planktothrix variants. In several strains the gene variants seem to be a result of recombination. Both NRPS and non-NRPS genes are dominated by purifying selection; however, sites subjected to positive selection were also detected. The presence of similar and well-separated Planktothrix variants with low internal genetic diversity indicates gene flow within Planktothrix populations. Further, the low genetic diversity found between lakes (similar range as within lakes) indicates gene flow also between Planktothrix populations and suggests recent, or recurrent, dispersals. Our data also indicate that recombination has resulted in new genetic variants. Stability within variants and the development of new variants are likely to be influenced by selection patterns and within-variant homologous recombination.
Authors
Dominika Srednicka-Tober Marcin Baranski Joanna Gromadzka-Ostrowska Krystyna Skwarlo-Sonta Ewa Rembialkowska Jana Hajslova Vera Schulzova Ismail Cakmak Levent Ozturk Tomasz Krolikowski Katarzyna Wisniewska Ewelina Hallmann Elzbieta Baca Mick Eyre Håvard Steinshamn Teresa Jordon Carlo LeifertAbstract
No abstract has been registered
Authors
Jarle Werner Bjerke Stef Bokhorst Terry V. Callaghan Matthias Zielke Gareth K. PhoenixAbstract
No abstract has been registered
Authors
Claudio Ioriatti F. Özlem Altindisli Jorunn Børve Lucia Adriana Escudero-Colomar Andrea Lucchi Fabio MolinariAbstract
No abstract has been registered
Editors
Bruce TalbotAbstract
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Authors
Arnfinn NesAbstract
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Authors
Christian PedersenAbstract
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Abstract
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Authors
Anne-Kristin Løes Martha EbbesvikAbstract
No abstract has been registered