Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2018
Forfattere
Gunn Strømeng Magne Nordang Skårn Kari Ørstad Arne Stensvand Katherine Ann Gredvig Nielsen May Bente BrurbergSammendrag
Det er ikke registrert sammendrag
Forfattere
Katherine Ann Gredvig Nielsen Gunn Strømeng Magne Nordang Skårn Kari Ørstad Arne Stensvand May Bente BrurbergSammendrag
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Forfattere
Gunn Strømeng Magne Nordang Skårn Kari Ørstad Arne Stensvand Katherine Ann Gredvig Nielsen May Bente BrurbergSammendrag
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Forfattere
Melissa Magerøy Hugh B. Cross Torstein Tengs Carl Gunnar Fossdal Pierre Petriacq Adam Vivian-Smith Tao Zhao Paal KrokeneSammendrag
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Forfattere
Heidi Udnes Aamot Katherine Ann Gredvig Nielsen Shiori Koga Anne Kjersti Uhlen Ulrike Böcker Erik Lysøe Guro Brodal Ruth Dill-Macky Ingerd Skow HofgaardSammendrag
The proportion of Norwegian wheat used for food has varied significantly during the recent decade, mainly because of the instability of factors that are essential to baking quality (i.e. protein content and gluten functionality). During the same period, serious contamination of Fusarium spp. and mycotoxins was observed in some grain lots [1, 2]. A project was established to generate greater knowledge of the interface between gluten functionality and effects of Fusarium species and other microorganisms on Norwegian wheat quality. Instances of severe degradation of gluten proteins that resulted in an almost complete loss of gluten functionality were observed in some lots of Norwegian wheat. The degradation of the gluten appeared to be caused by exogenous proteases. Metabarcoding of fungi and bacteria in these grain lots identified fungi within the Fusarium Head Blight complex, as well as one bacterial species, as candidate species for influencing gluten functionality. Some of these candidates were inoculated on wheat during flowering [3]. Analysis of baking quality of the flour from this experiment revealed a reduced proportion of un-extractable polymeric proteins (%UPP) and severe reductions in the gluten’s resistance to stretching (RMAX) in wheat flour from plants inoculated with Fusarium graminearum. Flour from wheat inoculated with Fusarium avenaceum was generally less infested, and showed minimal or no reduction in gluten functionality and %UPP compared to flour from the F. graminearum infested samples. Flour from wheat inoculated with Michrodochium majus is yet to be analysed. References 1. Koga, S., et al., Investigating environmental factors that cause extreme gluten quality deficiency in winter wheat (Triticum aestivum L.). Acta Agriculturae Scandinavica, Section B—Soil & Plant Science, 2016. 66(3): p. 237-246. 2. Hofgaard, I., et al., Associations between Fusarium species and mycotoxins in oats and spring wheat from farmers’ fields in Norway over a six-year period. World Mycotoxin Journal, 2016. 9(3): p. 365-378. 3. Nielsen, K.A.G., Effect of microorganisms on gluten quality in wheat., in Faculty of Biosciences. 2017, Norwegian University of Life Sciences: Ås.
Sammendrag
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Sammendrag
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Sammendrag
Dieback of European ash, caused by the ascomycete Hymenoscyphus fraxineus originating from Asia, has rapidly spread across Europe, and is threatening this keystone tree at a continental scale. High propagule pressure is characteristic to invasive species. Consistently, the enormous production of windborne ascospores by H. fraxineus in an ash forest with epidemic level of disease obviously facilitates its invasiveness and long distance spread. To understand the rate of build-up of propagule pressure by this pathogen following its local introduction, during 2011–2017 we monitored its sporulation at a newly infested ash stand in south-western Norway characterized with mild winters and cool summers. We also monitored the propagule pressure by Hymenoscyphus albidus, a non-pathogenic native species that competes for the same sporulation niche with H. fraxineus. During the monitoring period, crown condition of ash trees had impaired, and 20% of the dominant trees were severely damaged in 2017. H. fraxineus showed an exponential increase in spore production between 2012 and 2015, followed by drastic decline in 2016 and 2017. During 2011–2013, the two Hymenoscyphus species showed similar sporulation level, but thereafter spores of H. albidus were no longer detected. The data suggest that following local introduction, the population of H. fraxineus reaches rapidly an exponential growth stage if the local weather conditions are favorable for ascomata maturation across years. In the North Atlantic climate, summer temperatures critically influence the pathogen infection pressure, warm summers allowing the population to grow according to its biotic potential, whereas cold summers can cause a drastic decline in propagule pressure.
Sammendrag
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Sammendrag
Plants are exposed to various pathogens in their environment and have developed immune systems with multiple layers of defence to fight-back. However, often pathogens overcome the resistance barriers, infect the plants to cause the disease. Pathogens that cause diseases on economically important crop plants like strawberry incur huge losses to the agriculture industry. For example, The 2016 outbreak of strawberry grey mould (Botrytis cinerea) in Norway caused up to 95% crop losses. Outbreaks like this underline the importance of developing novel and sustainable tools to combat plant diseases, for example by increasing the plants’ natural disease resistance. Priming plant defences using chemical elicitors may be effective in providing the enhanced resistance against multiple pathogens. We have used β-aminobutyric acid (BABA) as a chemical priming agent to induce resistance in Fragaria vesca against Botrytis cinerea. Effects of BABA on disease progression and defence responses of Fragaria are being characterized using molecular tools like RNAseq, RT-PCR and ChIP. As priming chemicals may induce an epigenetic memory in treated plants, we also plan to study the histone methylation patterns in primed plants and the genes that are regulated. Our long-term aim is to understand the duration of the epigenetic memory and its cross-generational transmission to the progeny in Fragaria. Our results will help guide various crop protection strategies in addition to providing new insights to develop novel tools for plant disease management.