Fungal Diversity

, Volume 41, Issue 1, pp 17–28 | Cite as

Endophytic fungi in European aspen (Populus tremula) leaves—diversity, detection, and a suggested correlation with herbivory resistance

  • Benedicte R. Albrectsen
  • Lars Björkén
  • Akkamahadevi Varad
  • Åsa Hagner
  • Mats Wedin
  • Jan Karlsson
  • Stefan Jansson


Fungal endophytes are found in most seed plants, but their ecological function mainly remains elusive, except in pooid (or clavicipitalean) systems. The diversity and dynamics of endophytes in non clavicipitalean plants make studies of their ecological function challenging. This paper describes the advantage of using molecular techniques to survey the ecological function of endophytes in Populus tremula clones. About 1,000 endophyte isolates were distinguished using traditional methods; these isolates represented approximately 100 morphologically distinct groups. We generated 73 DNA-sequences (18S and ITS rDNA) from these groups and determined 33 distinct taxa. They represented the Basidiomycota and Ascomycota, including diverse Sordariomycetes and Dothideomycetes, and three sequences that were identified, by their ITS sequences, as a species of Epicoccum (a genus of supposedly unknown relation within the Ascomycota) were placed within the Pleosporales, in the 18S phylogeny. Primer pairs were designed for eleven of the fungi. Of these, three primers produced bands for a subset of Aspen samples. The primer pairs allowed endophytes in field samples to be readily identified, with a detection limit of 0.15 percent fungal DNA. The presence of fungi in Aspen clones was related to field damage by herbivores and the pathogen Venturia tremula. A negative association was found in two separate surveys between Aureobasidium sp. and herbivore damage, but we found no evidence that endophyte presence was related to a history of Venturia symptoms. This approach promises to enhance greatly the scope for qualitative and quantitative detection of endophyte communities, and to improve our ability to elucidate the ecological function of non clavicipitalean endophytes.


Aureobasidium Primer design Species richness Phylogeny Seasonality Gene activity Populus tremula Non clavicipitalean system 



This study was inspired by a workshop held by Dr. Mark Vicari in Umeå in 2005 financed by the Edlunds Brothers foundation to BRA. Financial support was received from the Swedish Research Council, the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (MW and SJ) and the Kempe foundation (BRA and SJ).

Supplementary material

13225_2009_11_MOESM1_ESM.xls (112 kb)
Suppl. Table 1 (XLS 112 kb)
13225_2009_11_MOESM2_ESM.doc (42 kb)
Suppl. Table 2 Summary of endophyte names for isolates in aspen 14/1 2008 (classification according to AFTOL) (DOC 42 kb)


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Copyright information

© Kevin D Hyde 2010

Authors and Affiliations

  • Benedicte R. Albrectsen
    • 1
  • Lars Björkén
    • 1
  • Akkamahadevi Varad
    • 1
  • Åsa Hagner
    • 2
    • 3
  • Mats Wedin
    • 4
  • Jan Karlsson
    • 1
  • Stefan Jansson
    • 1
  1. 1.Department of Plant PhysiologyUmeå University, Umeå Plant Science CentreUmeåSweden
  2. 2.Department of Ecology and Environmental ScienceUmeå UniversityUmeåSweden
  3. 3.Department of Forest Resource ManagementSwedish University of Agricultural SciencesUmeåSweden
  4. 4.Cryptogamic BotanyThe Swedish Museum of Natural HistoryStockholmSweden

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