Fungal associates of the tree-killing bark beetle, Ips typographus, vary in virulence, ability to degrade conifer phenolics and influence bark beetle tunneling behavior

Abstract

The bark beetle Ips typographus carries numerous fungi that could be assisting the beetle in colonizing live Norway spruce (Picea abies) trees. Phenolic defenses in spruce phloem are degraded by the beetle's major tree-killing fungus Endoconidiophora polonica, but it is unknown if other beetle associates can also catabolize these compounds. We compared the ability of five fungi commonly associated with I. typographus to degrade phenolic compounds in Norway spruce phloem. Grosmannia penicillata and Grosmannia europhioides were able to degrade stilbenes and flavonoids faster than E. polonica and grow on minimal growth medium with spruce bark constituents as the only nutrients. Furthermore, beetles avoided medium amended with phenolics but marginally preferred medium colonized by fungi. Taken together our results show that different bark beetle-associated fungi have complementary roles in degrading host metabolites and thus might improve this insect's persistence in well defended host tissues. (C) 2018 Elsevier Ltd and British Mycological Society. All rights reserved.

Keywords

Ips typographus; Fungal symbionts; Endoconidiophora; Grosmannia; Ophiostoma; Phenolic defenses; Detoxification; Complementary roles

Published in

Fungal Ecology
2019, volume: 38, pages: 71-79
Publisher: ELSEVIER SCI LTD

SLU Authors

• Zhao, Tao

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Plant Protection Network

UKÄ Subject classification

Zoology
Microbiology

Publication identifier

• DOI: https://doi.org/10.1016/j.funeco.2018.06.003

Permanent link to this page (URI)

https://res.slu.se/id/publ/99655