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.
2021
Forfattere
Albert Imsland Patrick Reynolds Thor Arne Hangstad Lauri Teemu Kapari Simo Maduna Snorre Hagen Ólöf Dóra Bartels Jónsdóttir Frank Spetland Ken Ståle LindbergSammendrag
To investigate the possible family influence on sea lice grazing of lumpfish on Atlantic salmon, ten families of lumpfish (N = 480) with a mean (± SD) weight of 54.8 ± 9.2 g were distributed among ten sea cages (5 × 5 × 5 m) each stocked with 400 Atlantic salmon with a mean (± SD) weight of 621.4 ± 9.2 g. All the ten cages were stocked with 48 lumpfish (12% stocking density). The stocking of cages was such that each cage consisted of two random families where full- and paternal half-sib families were randomly allocated to the different cages. There were clear differences in sea lice grazing efficacy, growth and cataract prevalence between the ten families assessed in this study. Lumpfish from families 2, 6 and 10 had the lowest mean weights but showed comparable growth rates compared to the other families throughout the study and this may be as a direct result of genetic influence. In addition, fish from these families had a significantly higher incidence of lice grazing of both L. salmonis and C. elongatus compared to the other families. Using mixed linear model to analyse the data revealed significant family and paternal effect on sea lice grazing. There was a trend for a reduction in sea lice grazing with increased size within each family. The results indicated that it was the smallest size classes of lumpfish (40–140 g) which exhibited higher sea lice grazing potential compared to the larger size classes within families. There were no clear differences in the lice grazing potential between male and female lumpfish within and between families. Overall, present findings showed that sea lice grazing of both L. salmonis and C. elongatus can be enhanced using targeted family production and if this behaviour has a genetic basis it may further enhanced through selection and targeted breeding programs.
Forfattere
Ulrike BayrSammendrag
Traditional landscape photographs reaching back until the second half of the nineteenth century represent a valuable image source for the study of long-term landscape change. Due to the oblique perspective and the lack of geographical reference, landscape photographs are hardly used for quantitative research. In this study, oblique landscape photographs from the Norwegian landscape monitoring program are georeferenced using the WSL Monoplotting Tool with the aim of evaluating the accuracy of point and polygon features. In addition, the study shows how the resolution of the chosen digital terrain model and other factors affect accuracy. Points mapped on the landscape photograph had a mean displacement of 1.52 m from their location on a corresponding aerial photograph, while mapped areas deviated on average 5.6% in size. The resolution of the DTM, the placement of GCPs and the angle of incidence were identified as relevant factors to achieve accurate geospatial data. An example on forest expansion at the abandoned mountain farm Flysetra in Mid-Norway demonstrates how repeat photography facilitates the georectification process in the absence of reliable ground control points (GCPs) in very old photographs.
Forfattere
Christophe Pelabon Elena Albertsen Arnaud Le Rouzic Cyril Firmat Geir Hysing Bolstad W. Scott Armbruster Thomas Fredrik HansenSammendrag
Although artificial-selection experiments seem well suited to testing our ability to predict evolution, the correspondence between predicted and observed responses is often ambiguous due to the lack of uncertainty estimates. We present equations for assessing prediction error in direct and indirect responses to selection that integrate uncertainty in genetic parameters used for prediction and sampling effects during selection. Using these, we analyzed a selection experiment on floral traits replicated in two taxa of the Dalechampia scandens (Euphorbiaceae) species complex for which G-matrices were obtained from a diallel breeding design. After four episodes of bidirectional selection, direct and indirect responses remained within wide prediction intervals, but appeared different from the predictions. Combined analyses with structural-equation models confirmed that responses were asymmetrical and lower than predicted in both species. We show that genetic drift is likely to be a dominant source of uncertainty in typically-dimensioned selection experiments in plants and a major obstacle to predicting short-term evolutionary trajectories.
Forfattere
Nina TrandemSammendrag
Det er ikke registrert sammendrag
Forfattere
YeonKyeong Lee Payel Bhattacharjee Marcos Viejo Ole Christian Lind Brit Salbu Dag Anders Brede Jorunn Elisabeth OlsenSammendrag
Det er ikke registrert sammendrag
Forfattere
Paul Vargas Jentzsch Christian Sandoval Pauker Paola Zárate Pozo Marco Sinche Serra Gonzalo Jácome Camacho Victor Rueda-Ayala Patricia Garrido Luis Ramos Guerrero Valerian CiobotăSammendrag
Essential oils are liquid mixtures of volatile compounds extracted from plants. Their quality is usually controlled via gas chromatography (GC), although with limitations when adulterants are nonvolatile substances. The essential oils of lavender (Lavandula angustifolia Mill.), peppermint (Mentha piperita L.), patchouli (Pogostemon cablin Benth), and their adulterated versions were measured by GC coupled to flame ionization detector (GC-FID) and Raman spectroscopy. Canola oil, a nonvolatile substance, was used as the adulterant. The adulterated essential oils contained 1%, 3%, 5%, 10%, 15%, and 20% (v/v) of canola oil. Chromatograms of the adulterated essential oils containing 20% (v/v) of canola oil showed decrements in peak areas of the essential oil components, compared with peaks of the pure essential oils. The highest decrements were observed for the adulterated essential oil of patchouli. In general, detection of adulterated essential oils by simple visual inspection of the Raman features was difficult, due to slight differences observed in the spectra. Principal Components Analysis (PCA) allowed achieving a good spectral discrimination between pure and adulterated essential oils. These results suggest that Raman spectroscopy can overcome limitations of GC-based methods, thus becoming an interesting alternative and complementary technique for quality control of essential oils.
Sammendrag
Rapport til Statsforvalteren i Rogaland. 1.nov. 2021
Forfattere
Håvard EikemoSammendrag
Potetkreft er en fryktet sykdom i potetdyrkingen, siden den kan føre til totalt avlingstap hvis den ikke bekjempes. Den har ikke vært påvist i Norge siden 1994, men økende forekomster i Sverige og Danmark de siste årene har gjort sjukdommen mer aktuell. Utbruddene i Sverige og Danmark har også vært forårsaket av raser som kan angripe mange av de vanligste potetsortene i Norge. Formålet med dette OK-programmet er å sjekke tilstedeværelse av potetkreft i Norge, samt teste metodikken rundt visuell påvisning og molekylær testing for potetkreft. Selv om man regner potetkreft som ikke forekommende i Norge er det viktig å gjennomføre denne typen undersøkelser for å få dokumentert statusen. Totalt ble 349 prøver vurdert i 2020, og alle var negative ved visuell bedømmelse. Det ble heller ikke funnet noe mistenkelig som førte til at prøvene burde kontrolleres ved PCR. Av de 349 prøvene ble 53 prøver tilfeldig valgt ut for kontroll ved hjelp av PCR, og også disse var negative. Resultatene fra 2020 viser at status for potetkreft i Norge henhold til ISPM 8 er å anse som «Absent: pest no longer present».
Forfattere
Wendy Marie WaalenSammendrag
Det er ikke registrert sammendrag
Forfattere
Anita SønstebySammendrag
Det er ikke registrert sammendrag