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.
2015
Forfattere
Sølvi WehnSammendrag
This paper reports on the performance of the red-listed Primula scandinavica, endemic to Scandinavia. The study took place in Jotunheimen, Norway. We evaluated occurrence, density and sexual reproduction variables (number of fertile individuals and number of seed capsules). Habitats were registered as land-cover categories (historical and current; broad habitat types) and habitat patch classes (semi-natural and natural; fine-grained habitat types). Spatial overlay analyses and maximum likelihood tests of generalized linear mixed models (GLMMs) were performed to assess the habitat quality of the land-cover categories and the habitat patch classes. In most (96%) of the observed occurrences the species was located at a site that had open vegetation 40 years ago but is now becoming forested or covered by shrubs. The highest densities of P. scandinavica were found in “heathland” and “grassland in transition into woodland”, while the potential for sexual reproduction was highest in “grassland” and lowest in “grassland in transition into woodland”. The results indicate that many of the populations in the study area are remnants and that the habitats of highest quality are semi-natural habitat patches. The changed land use practices in mountain areas have resulted and will result in fewer and smaller populations. However, as also climatic conditions will change it is not straightforward to predict the future performance of P. scandinavica.
Forfattere
Hanne Kathrine Sjølie Hans Asbjørn K. Sørlie Bjørn Tveite Birger SolbergSammendrag
This study compares the responses of two Swedish 5-year predictive stand-level functions with the observed responses in 721 fertilization experiment plots in Norway fertilized with nitrogen (N). All plots are single-species consisting of Norway spruce (Picea abies (L.) H. Karst.) or Scots pine (Pinus sylvestris L.) fertilized with ammonium nitrate (AN) or urea. The correlations between the observed and the two predicted responses were 0.34–0.40 for all plots taken together. One response function performed well on average, but underestimated the response in pine plots and overestimated the response in spruce plots. The second function overpredicted the response on the full dataset, in spruce plots and old forest, but performed well in pine plots. Both functions overestimated the growth response in high-productive plots. Higher N deposition in Norway than in Sweden may count for parts of the deviations. Testing of fertilization functions on new datasets is rare, but important part of the evaluation of functions. As the functions are not well fit for predicting the growth response in spruce and high-productive plots in our sample, new functions that include N deposition are welcome.
Forfattere
Trygve S. AamlidSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Seyda Ozkan Søren Østergaard Turid StrømSammendrag
Det er ikke registrert sammendrag
Forfattere
Live Lingaas Nesse Anne Marie Bakke Trine Eggen Kristian Hoel Magne Kaldhusdal Einar Ringø Siamak Pour Yazdankhah Erik-Jan Lock Rolf Erik Olsen Robin Ørnsrud Åshild KrogdahlSammendrag
Det er ikke registrert sammendrag
Sammendrag
Leaf blotch diseases in wheat can cause yield losses above 30 %. The necrotrophic fungus Parastagonospora nodorum is the dominating leaf blotch pathogen in Norwegian spring wheat. It has been well documented at the seedling stage that the pathogen produces necrotrophic effectors (NEs) which induces cell death in plants carrying susceptibility genes (Snn), allowing the necrotroph to enter. However, the role of these interactions under field conditions is less researched. In this study, we conducted field experiments with bi-parental and association mapping populations of spring wheat, to investigate the role of NE/Snn in adult plant resistance. The populations have been genotyped with the Illumina 90 K SNP chip, P. nodorum has high genetic diversity and both sexual and asexual reproduction, but the actual adaptation of the pathogen population to cultivars with different levels of resistance is not well studied. We are screening a collection of Norwegian isolates from known host sources to look for differences in NE-frequencies and haplotype distribution. The mapping populations are also inoculated and infiltrated with culture filtrates from single isolates on the seedling stage. Isolates involved in novel interactions will be deepsequenced in order to look for candidate effector genes. Potential effector proteins will be purified by LPC and HPLC to confirm their role in disease development.
Sammendrag
Leaf blotch diseases in wheat can cause yield losses above 30 %. The necrotrophic fungus Parastagonospora nodorum is the dominating leaf blotch pathogen in Norwegian spring wheat. It has been well documented at the seedling stage that the pathogen produces necrotrophic effectors (NEs) which induces cell death in plants carrying susceptibility genes (Snn), allowing the necrotroph to enter. However, the role of these interactions under field conditions is less researched. In this study, we conducted field experiments with bi-parental and association mapping populations of spring wheat, to investigate the role of NE/Snn in adult plant resistance. The populations have been genotyped with the Illumina 90 K SNP chip, P. nodorum has high genetic diversity and both sexual and asexual reproduction, but the actual adaptation of the pathogen population to cultivars with different levels of resistance is not well studied. We are screening a collection of Norwegian isolates from known host sources to look for differences in NE-frequencies and haplotype distribution. The mapping populations are also inoculated and infiltrated with culture filtrates from single isolates on the seedling stage. Isolates involved in novel interactions will be deepsequenced in order to look for candidate effector genes. Potential effector proteins will be purified by LPC and HPLC to confirm their role in disease development.