Microbial Ecology

, Volume 75, Issue 1, pp 7–9 | Cite as

Symbiont Spillover from Invasive to Native Woodwasps

  • Ann E. HajekEmail author
  • David C. Harris
  • Tonya D. Bittner


Hosts and their associated microbes are being increasingly introduced around the world, which can lead to novel host/microbe associations via new sympatries. Woodwasps (Hymenoptera: Siricidae) are able to utilize wood for its nutrients due to obligate mutualistic associations with white rot fungi in the genus Amylostereum and when invasive woodwasps are introduced to new areas, their symbionts accompany them. There is increasing evidence that woodwasp-fungus associations previously believed to be highly specific are actually flexible. We show that in North America, both Urocerus albicornis and Urocerus cressoni, which develop in trees in the Pinaceae, usually use Amylostereum chailletii but sometimes carry an Amylostereum areolatum strain putatively introduced to North America by the invasive woodwasp Sirex noctilio. Symbiont spillover from invasive to native hosts is a source of new host/introduced symbiont associations that could result in changes in microbes and host fitness with the potential to impact communities.


Mutualist Amylostereum White rot fungus Fungal fidelity Symbiont Urocerus 



We thank Ryan Kepler, Sergio Angeli, and Stefan Long for isolating fungi from mycangia and organizing fungal cultures and Louela Castrillo for advice on the manuscript. This study was funded by USDA Forest Service Cooperative Agreement 12-CA-11420004-043 and USDA NIFA AFRI 2009-02182.


  1. 1.
    Wingfield MJ, Garnas JR, Hajek AE, Hurley BP, de Beer ZW, Taerum SJ (2016) Novel and co-evolved associations between insects and microorganisms as drivers of forest pestilence. Biol Invasions 18:1045–1056CrossRefGoogle Scholar
  2. 2.
    Hochachka WM, Dhondt AA, Dobson A, Hawley DM, Ley DH, Lovette IJ (2017) Multiple host transfers, but only one successful lineage in a continent-spanning emergent pathogen. Proc R Soc B Biol Sci 280:20131068CrossRefGoogle Scholar
  3. 3.
    Thompson BM, Bodart J, McEwen C, Gruner DS (2014) Adaptations for symbiont-mediated external digestion in Sirex noctilio (Hymenoptera: Siricidae). Ann Entomol Soc Amer 107:453–460CrossRefGoogle Scholar
  4. 4.
    Gilbertson RL (1984) Relationships between insects and wood-rotting Basidiomycetes. In: Wheeler Q, Blackwell M (eds) Fungus-insect relationships: perspectives in ecology and evolution. Columbia University Press, NY, pp. 130–165Google Scholar
  5. 5.
    Nielsen C, Williams DW, Hajek AE (2009) Putative source of the invasive Sirex noctilio fungal symbiont, Amylostereum areolatum, in the eastern United States and its association with native siricid woodwasps. Mycol Res 113:1242–1253CrossRefPubMedGoogle Scholar
  6. 6.
    Hajek AE, Nielsen C, Kepler RM, Long SJ, Castrillo L (2013) Fidelity among Sirex woodwasps and their fungal symbionts. Microb Ecol 65:753–762CrossRefPubMedPubMedCentralGoogle Scholar
  7. 7.
    Wooding AL, Wingfield MJ, Hurley BP, Garnas JR, De Groot P, Slippers B (2013) Lack of fidelity revealed in an insect–fungal mutualism after invasion. Biol Lett 9(4):20130342CrossRefPubMedPubMedCentralGoogle Scholar
  8. 8.
    López S, González M, Goldarazena A (2012) Urocerus albicornis (Fabricius, 1781) (Hymenoptera: Siricidae), a new exotic horntail for the Iberian Peninsula. EPPO Bull 42:150–153CrossRefGoogle Scholar
  9. 9.
    Castrillo LA, Hajek AE, Pajares JA, Thomsen IM, Csóka G, Kenaley SC, Kepler RM, Zamora P, Angeli S (2015) Multilocus genotyping of Amylostereum spp. associated with Sirex noctilio and other woodwasps from Europe reveal clonal lineage introduced to the US. Fung Biol 119:595–604CrossRefGoogle Scholar
  10. 10.
    Thomsen IM, Harding S (2011) Fungal symbionts of siricid woodwasps: isolation techniques and identification. For Pathol 41:325–333CrossRefGoogle Scholar
  11. 11.
    Gardes M, Bruns TD (1993) ITS primers with enhanced specificity for basidiomycetes—application to the identification of mycorrhizae and rusts. Molec Ecol 2:113–118CrossRefGoogle Scholar
  12. 12.
    White TJ, Bruns T, Lee S, Taylor J (1990) Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. In: Innis MA, Gelfland DH, Sninsky JJ, White TJ (eds) PCR protocols: a guide to methods and applications. Academic Press, San Diego, pp. 315–322Google Scholar
  13. 13.
    Hoebeke ER, Haugen DA, Haack RA (2005) Sirex noctilio: discovery of a Palearctic siricid woodwasp in New York. Newsl Mich Entomol Soc 50:24–25Google Scholar
  14. 14.
    Fitza KNE, Tabata M, Kanzaki N, Kimora K, Garnas J, Slippers B (2016) Host specificity and diversity of Amylostereum associated with Japanese siricids. Fung Ecol 24:76–81CrossRefGoogle Scholar
  15. 15.
    Olatinwo R, Allison J, Meeker J, Johnson W, Streett D, Aime MC, Carlton C (2013) Detection and identification of Amylostereum areolatum (Russulales: Amylostereaceae) in the mycangia of Sirex nigricornis (Hymenoptera: Siricidae) in central Louisiana. Environ Entomol 42:1246–1256CrossRefPubMedGoogle Scholar
  16. 16.
    Ryan K, Hurley BP (2012) Life history and biology of Sirex noctilio. In: Slippers B, de Groot P, Wingfield MJ (eds) The Sirex Woodwasp and its fungal symbiont: research and management of a worldwide invasive pests. Springer, Dordrecht, pp. 15–20CrossRefGoogle Scholar
  17. 17.
    Schiff NM, Goulet H, Smith DR, Boudreault C, Wilson AD, Scheffler BE (2012) Siricidae (Hymenoptera: Symphyta: Siricoidea) of the Western Hemisphere. Can J Arthro Ident No 21:305Google Scholar

Copyright information

© Springer Science+Business Media, LLC 2017

Authors and Affiliations

  • Ann E. Hajek
    • 1
    Email author
  • David C. Harris
    • 1
  • Tonya D. Bittner
    • 1
  1. 1.Department of EntomologyCornell UniversityIthacaUSA

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