Hopp til hovedinnholdet

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.

2019

To document

Abstract

Four species of the destructive forest pathogen Heterobasidion annosum sensu lato (s.l.) are present in Europe: H. annosum sensu stricto (s.s.), H. abietinum and H. parviporum are native species, while H. irregulare is a non‐native invasive species currently reported only in Italy, yet recommended for regulation throughout Europe. In this study, real‐time PCR detection tests were developed for each of the four species, which can be used simultaneously or individually thanks to probes labelled with species‐specific fluorescent dyes. The different performance criteria of each assay were evaluated, and it was determined that they were theoretically capable of detecting amounts of DNA corresponding to 311, 29 and 29 cell nuclei in H. annosum s.s., H. irregulare and H. parviporum, respectively. The specificity of each assay was assessed with a wide set of strains. Real‐time PCR tests successfully detected Heterobasidion species from 36 fruiting bodies taken from the forest, as well as from artificially inoculated or naturally infected wood samples. The multiplex real‐time PCR assays developed in this study could have practical applications both in forest management and in phytosanitary monitoring.

2018

To document

Abstract

Political action can reduce introductions of diseases caused by invasive forest pathogens (IPs) and public support is important for effective prevention. The public’s awareness of IP problems and the acceptability of policies aiming to combat these pathogens were surveyed in nine European countries (N = 3469). Although awareness of specific diseases (e.g., ash dieback) varied, problem awareness and policy acceptability were similar across countries. The public was positive towards policies for informational measures and stricter standards for plant production, but less positive towards restricting public access to protected areas. Multilevel models, including individual and country level variables, revealed that media exposure was positively associated with awareness of IP problems, and strengthened the link between problem awareness and policy acceptability. Results suggest that learning about IPs through the media and recognizing the associated problems increase policy acceptability. Overall, the study elaborates on the anthropogenic dimension of diseases caused by IPs.

To document

Abstract

Accelerating international trade and climate change make pathogen spread an increasing concern. Hymenoscyphus fraxineus, the causal agent of ash dieback, is a fungal pathogen that has been moving across continents and hosts from Asian to European ash. Most European common ash trees (Fraxinus excelsior) are highly susceptible to H.fraxineus, although a minority (~5%) have partial resistance to dieback. Here, we assemble and annotate a H.fraxineus draft genome, which approaches chromosome scale. Pathogen genetic diversity across Europe and in Japan, reveals a strong bottleneck in Europe, though a signal of adaptive diversity remains in key host interaction genes. We find that the European population was founded by two divergent haploid individuals. Divergence between these haplotypes represents the ancestral polymorphism within a large source population. Subsequent introduction from this source would greatly increase adaptive potential of the pathogen. Thus, further introgression of H.fraxineus into Europe represents a potential threat and Europe-wide biological security measures are needed to manage this disease.