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.
2017
Abstract
The impact of Delphinella shoot blight (Delphinella abietis) and Grovesiella canker (Grovesiella abieticola) on subalpine (Abies lasiocarpa) and corkbark fir (A. lasiocarpa var. arizonica) in a provenance trial in Idaho (ID) was evaluated in 2013. Both pathogens were previously reported from North America on fir species. D. abietis had been found on subalpine fir in USA, but not in ID, and G. abieticola on grand fir (Abies grandis) in ID, but not on subalpine or corkbark fir. D. abietis kills current-year needles and in severe cases buds and shoots, and G. abieticola results in dead shoots and branches and can eventually kill whole trees. Significant differences between provenances in susceptibility to D. abietis and G. abieticola were observed in the provenance trial in ID. In general, subalpine fir was more susceptible to both diseases than corkbark fir. In 2013, D. abietis was also found on subalpine fir in the Puget Sound area of Washington State and G. abieticola was seen on white fir (Abies concolor), but neither disease was detected in native stands of subalpine fir in Washington State. Morphological features of both fungi were described from samples collected in the provenance trial in ID in May 2016.
Authors
B. M. Kisselstein Lance Cadle-Davidson W. Weldon B. B. Forcelini Natalia A. Peres M. McGrath Belachew Asalf Tadesse Arne Stensvand David M. GadouryAbstract
No abstract has been registered
Authors
Isabella Børja Douglas L. Godbold Jan Světlík Nina Elisabeth Nagy Roman Gebauer Josef Urban Daniel Volařík Holger Lange Paal Krokene Petr Čermák Toril Drabløs EldhusetAbstract
Global warming will most likely lead to increased drought stress in forest trees. We wanted to describe the adaptive responses of fine roots and fungal hyphae, at different soil depths, in a Norway spruce stand to long-term drought stress induced by precipitation exclusion over two growing seasons. We used soil cores, minirhizotrons and nylon meshes to estimate growth, biomass and distribution of fine roots and fungal hyphae at different soil depths. In control plots fine roots proliferated in upper soil layers, whereas in drought plots there was no fine root growth in upper soil layers and roots mostly occupied deeper soil layers. Fungal hyphae followed the same pattern as fine roots, with the highest biomass in deeper soil layers in drought plots. We conclude that both fine roots and fungal hyphae respond to long-term drought stress by growing into deeper soil layers.
Abstract
During August 2013, white-grayish lesions, typical of Sclerotinia stem rot, had developed around leaf axils on the stems of turnip rape ‘Pepita’ in a field at the NIBIO research station Apelsvoll in Oppland County, Norway. Sclerotia were collected from inside infected turnip rape stubble and from harvested seeds, surface sterilized, bisected, and placed onto potato dextrose agar (PDA). Following 1 to 2 days incubation at 20°C, fast-growing white mycelium characteristic of Sclerotinia was observed, and within 5 to 7 days, new sclerotia had started to develop. Sclerotia size and growing pattern although variable was characteristic of S. sclerotiorum. DNA extraction, PCR amplification, and sequencing of the ITS regions of the rDNA was then carried out for 20 isolates. BLASTn analysis of 475 bp amplicons showed that 15 isolates were S. sclerotiorum, while five were identified as S. subarctica (previously called Sclerotinia sp 1; Holst-Jensen et al. 1998; Winton et al. 2006, 2007), with 100% identity to a U.K. S. subarctica isolate (Clarkson et al. 2010). A representative ITS region sequence was deposited in GenBank (accession no. KX929095). The identity of the S. subarctica isolates was further confirmed by the lack of a 304-bp intron in the LSU rDNA compared with S. sclerotiorum (Holst-Jensen et al. 1998), which was visualized by PCR amplification and gel electrophoresis. Sclerotia of two S. subarctica isolates were placed on PDA and incubated for 7 days. Agar plugs of actively growing mycelium were used for the pathogenicity testing of spring oilseed rape plants (‘Mosaik’) in the greenhouse. Plants were inoculated at growth stage BBCH 57/59 (preflowering) and BBCH 64 (40% of flowers open) by attaching two PDA plugs of actively growing mycelium per main stems with small needles, using four plants per treatment. Noninoculated PDA agar plugs were attached to the control plants. The experiment was repeated three times. Symptoms typical of stem rot appeared after 1 to 2 weeks of incubation at 16 to 20°C, 100% relative humidity. Stems started to develop white lesions with fluffy mycelium around the inoculation sites. Control plants did not show the characteristic symptoms for Sclerotinia infection. After senescence of the plants, sclerotia were collected from inside the stems and cultured on PDA. White mycelium started to grow after 1 to 2 days and new sclerotia were formed within 7 days, similar to the ones used for producing the initial isolate. Brassica oil seed crops are cultivated as important break crops in the cereal-based production system in Norway and can be severely affected by Sclerotinia stem rot. The disease is observed in all regions where Brassica oil seed crops are grown, and in severe cases, a reduction in oilseed yield of 25% has been recorded in untreated control treatments of fungicide trials. Although S. subarctica has been previously reported on wild hosts (Holst-Jensen et al. 1998), this is the first report of the pathogen on a crop plant in Norway. In the United Kingdom, Clarkson et al. (2010) demonstrated pathogenicity of S. subarctica isolated from Ranunculus acris on oilseed rape. As symptoms for S. subarctica and S. sclerotiorum are indistinguishable, S. subarctica might be present undetected in many farmer fields.
Abstract
No abstract has been registered
Authors
K.A.G Nielsen Ingerd Skow Hofgaard Shiori Koga H.U. Aamot Ulrike Böcker Erik Lysøe Guro Brodal Ruth Dill-Macky Anne Kjersti UhlenAbstract
No abstract has been registered
Authors
Isabella Børja Kjell Andreassen Jan Čermák Lise Dalsgaard Arthur Gessler Douglas L. Godbold Rainer Hentschel Zachary E. Kayler Paal Krokene Nadezhda Nadezhdina Sabine Rosner Svein Solberg Halvor Solheim Jan Svetlik Mari Mette Tollefsrud Ole Einar TveitoAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
D Elliot Andrea Ficke Lorenz Hartl Sarah Holdgate Lise Nistrup Jørgensen Annemarie Justesen Volker Mohler Morten Lillemo Ian Mackay Min Lin Beatrice Corsi Caroline Moffat R. Oliver Kar-Chun Tan Pao Theen See Melanie Stadlmeier Judith Turner James CockramAbstract
No abstract has been registered
Authors
Andrea FickeAbstract
No abstract has been registered