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.
2021
Authors
Kirsten TørresenAbstract
No abstract has been registered
Authors
Kirsten TørresenAbstract
No abstract has been registered
Authors
Kirsten TørresenAbstract
No abstract has been registered
Authors
Kirsten TørresenAbstract
No abstract has been registered
Authors
Kirsten TørresenAbstract
No abstract has been registered
Authors
Daniel Powell Ewald Groβe-Wilde Paal Krokene Amit Roy Amrita Chakraborty Christer Löfstedt Heiko Vogel Martin N. Andersson Fredrik SchlyterAbstract
Conifer-feeding bark beetles are important herbivores and decomposers in forest ecosystems. These species complete their life cycle in nutritionally poor substrates and some can kill enormous numbers of trees during population outbreaks. The Eurasian spruce bark beetle (Ips typographus) can destroy >100 million m3 of spruce in a single year. We report a 236.8 Mb I. typographus genome assembly using PacBio long-read sequencing. The final phased assembly has a contig N50 of 6.65 Mb in 272 contigs and is predicted to contain 23,923 protein-coding genes. We reveal expanded gene families associated with plant cell wall degradation, including pectinases, aspartyl proteases, and glycosyl hydrolases. This genome sequence from the genus Ips provides timely resources to address questions about the evolutionary biology of the true weevils (Curculionidae), one of the most species-rich animal families. In forests of today, increasingly stressed by global warming, this draft genome may assist in developing pest control strategies to mitigate outbreaks.
Authors
Tomáš Hlásny Louis König Paal Krokene Marcus Lindner Claire Montagné-Huck Jörg Müller Hua Qin Kenneth F. Raffa Mart-Jan Schelhaas Miroslav Svoboda Heli Viiri Rupert SeidlAbstract
Purpose of Review Outbreaks of tree-killing bark beetles have reached unprecedented levels in conifer forests in the northern hemisphere and are expected to further intensify due to climate change. In parts of Europe, bark beetle outbreaks and efforts to manage them have even triggered social unrests and political instability. These events have increasingly challenged traditional responses to outbreaks, and highlight the need for a more comprehensive management framework. Recent Findings Several synthesis papers on different aspects of bark beetle ecology and management exist. However, our understanding of outbreak drivers and impacts, principles of ecosystem management, governance, and the role of climate change in the dynamics of ecological and social systems has rapidly advanced in recent years. These advances are suggesting a reconsideration of previous management strategies. Summary We synthesize the state of knowledge on drivers and impacts of bark beetle outbreaks in Europe and propose a comprehensive context-dependent framework for their management. We illustrate our ideas for two contrasting societal objectives that represent the end-members of a continuum of forest management goals: wood and biomass production and the conservation of biodiversity and natural processes. For production forests, we propose a management approach addressing economic, social, ecological, infrastructural, and legislative aspects of bark beetle disturbances. In conservation forests, where non-intervention is the default option, we elaborate under which circumstances an active intervention is necessary, and whether such an intervention is in conflict with the objective to conserve biodiversity. Our approach revises the current management response to bark beetles in Europe and promotes an interdisciplinary social-ecological approach to dealing with disturbances.
Authors
Paal KrokeneAbstract
No abstract has been registered
Abstract
The spruce bark beetle Ips typographus is the most damaging pest in European spruce forests and has caused great ecological and economic disturbances in recent years. Although native to Eurasia, I. typographus has been intercepted more than 200 times in North America and could establish there as an exotic pest if it can find suitable host trees. Using in vitro bioassays, we compared the preference of I. typographus for its coevolved historical host Norway spruce (Picea abies) and two non-coevolved (naïve) North American hosts: black spruce (Picea mariana) and white spruce (Picea glauca). Additionally, we tested how I. typographus responded to its own fungal associates (conspecific fungi) and to fungi vectored by the North American spruce beetle Dendroctonus rufipennis (allospecific fungi). All tested fungi were grown on both historical and naïve host bark media. In a four-choice Petri dish bioassay, I. typographus readily tunneled into bark medium from each of the three spruce species and showed no preference for the historical host over the naïve hosts. Additionally, the beetles showed a clear preference for bark media colonized by fungi and made longer tunnels in fungus-colonized media compared to fungus-free media. The preference for fungus-colonized media did not depend on whether the medium was colonized by conspecific or allospecific fungi. Furthermore, olfactometer bioassays demonstrated that beetles were strongly attracted toward volatiles emitted by both con- and allospecific fungi. Collectively, these results suggest that I. typographus could thrive in evolutionary naïve spruce hosts if it becomes established in North America. Also, I. typographus could probably form and maintain new associations with local allospecific fungi that might increase beetle fitness in naïve host trees.
Lecture – Natural disturbance factors affecting forests and possible mitigation actions
Paal Krokene
Authors
Paal KrokeneAbstract
No abstract has been registered