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.
2009
Sammendrag
As part of a project on cultivation and industrial exploitation of European Blueberry (Vaccinium myrtillus ) started in 2008, berries from different wild populations from South, Mid and North Norway were investigated. One aspect of fruit quality analyses was to identify and describe blueberry aroma profiles. Volatiles were extracted by headspace solid-phase microextraction (HS-SPME) and analysed by gas chromatography/ mass spectrometry (GC/MS) (Rohloff, 2004). More than 100 compounds could be identified based on MS database search and retention indices, also comprising aroma impact compounds not being described in blueberries earlier (Sydow & Anjou, 1969). Detected aliphatic and aromatic structures belonged to chemical groups such as alkanes, acids, alcohols, aldehydes, esters, ketones and mono- and sesquiterpenes. Ten major compounds (mostly C4-, C6- and C9-structures) accounted for averagely 65-75 % relative amount of all detected peaks. However, HS-SPME analyses revealed complex volatile profiles including terpenes (>20 compounds, e.g. p-cymene, 1,8-cineole, linalool) and aromatic structures (>10 compounds, e.g. benzaldehyde, ethyl benzoate, 2-phenylethyl acetate, benzyl benzoate), which contribute to the characteristic and flavourful blueberry aroma.
Sammendrag
In a four year project (2008-2011) the potential will be examined for commercial production of the European blueberry (V. myrtillus ) inNorway, with most effort investigating semi-cultivation practices on forestland. However, adaption to growth on agricultural land will alsobe in focus as well as selecting superior clones adapted to Norwegian regions, and development of effective propagation methods. Also, it isgiven priority to find how the European blueberry (EB) react to climatic parameters, which will be examined under controlled experimentsand paralleled by meteorological data from forest fields.
Forfattere
Rolf NestbySammendrag
Konklusjon.Innvik: Både Agromarin og Marihøne+ gir god avling. Ingen forskjell på gjødselmengder. Ingen positiv virkning av dryppgjødsling. Brønnøysund: Både Agromarin og Marihøne gir god avling.Samspill drypp og fastgjødsel i 2009: Dryppgjødsel + fastgjødsel var positivt i 2009. Harstad: Økt mengde fastgjødsel ga større avling. Agromarin er dårligere enn Marihøne+: K-effekt? Dryppgjødsel + fastgjødsel ga større avling
Forfattere
Eivind UlebergSammendrag
QTL mapping experiments aim to find the genes or mutations that contribute to phenotypic variance. This knowledge is important for biological understanding and can be utilized, e.g. for medical or breeding purposes. QTL mapping methods can be categorised as linkage analysis (LA) methods, linkage disequilibrium (LD) based methods and methods combining linkage and linkage disequilibrium analysis (LLD). The basic difference between LA and LD analysis is the calculations of the probability that two animals carry genes that are identical-by-descent (IBD) at a given point on the chromosome. LA is based on within family IBD, whereas LD is based on population-wide IBD probabilities. LA analysis is dependent on recombinations that can be observed in the genotyped data, which limits the accuracy. LD is based on historical recombinations and can find short confidence intervals, but is likely to result in false positives due to spurious associations between markers and QTL. To avoid the problems of separate LA or LD analysis, approaches combining linkage and linkage disequilibrium mapping (LLD) have been proposed. The main objective of this thesis has been to make maximum use of genotyping information from QTL mapping experiments for detecting as many as possible QTL and position them as precisely as possible. Specific issues addressed have been single versus multiple mapping methods (paper 1), the effects of including the causative mutation amongst the markers in QTL mapping experiments (paper 2) and developing a statistical test to distinguish causative from non-causative SNPs (paper 3).In paper 1 single and multi QTL fine-mapping methods were compared in a situation where two QTL were located in the analysed region. The single QTL method had problems differentiating between two QTLs when these were closely located, which often resulted in discovery of a ghost QTL between the real ones, or no clear QTL discovery. The multi QTL approach found evidence of both QTLs even when these were close (15cM). Although these differences to some extent may be explained by the different statistical approaches used by the two methods, the main conclusion from this paper is that multi QTL mapping methods should be applied when analysing QTL data. Paper 2 investigated the effect of including the causative SNP amongst the markers in a QTL mapping experiment. Both power and precision was greatly increased by including the causative mutation. When the causative mutation was not included amongst the markers the LLD method had clearly better precision and power than the association method. The increased power from including the causative SNP as marker was larger with association mapping than LLD mapping, and when the causation was included amongst the markers the methods had similar power and precision. These differences were partly due to the test-statistics, as the association method tested directly on the markers, while the LLD method tested the midpoints of the marker brackets. Including the causative mutation as marker increases the possibility of discovering QTLs of smaller effects.The increased power and precision obtained by including the causative SNP amongst the markers, was in paper 3 used to develop a test to confirm causative SNPs. The ‘Causative SNP Test" obtained a power of 28 % in this study, while the power of QTL detection was 97 %. The low power of CST was due to strong LD between the analyzed markers. All confirmed SNPs were truly causative and correctly positioned by the CST test. Thus, if positive, this test provides a lot of evidence for causality.Results from QTL mapping experiments so far indicates that most complex traits are controlled by many genes, with mainly small effects on variance. Currently available genome sequences and sample sizes has limited power to detect QTLs with small effects and thus, reported QTLs so far only explains small proportions of observed phenotypic variance for most traits. Future prospects of complete genome sequences will increase the power to find QTLs. The recent strong focus on genome-wide association studies (GWAS) will be expected also for future experiments. This study has shown that future QTL mapping experiments should use multi QTL approaches, to avoid bias from additional QTLs. As the power of QTL mapping is greatly increased by including the causative mutation amongst the markers, one should also aim to design experiments that have high power to distinguish causative from non-causative mutations. Experiments where the relationship between the individuals is low, as is generally the case in human GWAS studies, seem to achieve this. The causality can in the next step be tested by the proposed CST test.
Forfattere
Gunhild Børtnes Ruth MordalSammendrag
Det er ikke registrert sammendrag
Forfattere
Gunhild Børtnes Ruth MordalSammendrag
Tyrkermynte (Dracocephalum moldavicum) er ein eittårig vekst som vert 30-60 cm høg. Den har vore mykje brukt i folkemedisinen der den kjem frå i Sør-Sibir og Himaleya. Aromaen minner om sitronmelisse og kan brukast som denne i salatar og i fiskerettar. Tyrkermynte er også ein vakker prydplante som med fordel også kan takast i bruk i Norge.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Vibeke Lind Jan Berg Lars Olav Eik Svein Eilertsen Jørgen A.B. Mølmann Margrethe Hersleth Nils Kristian Afseth Espen HauglandSammendrag
With the objective of studying the effects of production systems on meat quality, 75 Norwegian White Sheep lambs were subjected to one of the following treatments: continuous grazing on a semi-natural lowland pasture until slaughtering (Control); continuous grazing followed by either stall-feeding on concentrate and grass silage or grazing ryegrass pasture for 44 or 24 days before slaughtering (Conc44, Conc24, Rye44, Rye24). Loin samples of M. longissimus dorsi including the subcutaneous fat were analysed for sensory attributes and fatty acid composition. Compared with the control group, a lower intensity of acid taste (P<0.05) and a lower content of C18:3n-6 fatty acids (P<0.001) were observed in the Conc44 group. The n-6/n-3 ratio was higher (P<0.001) in meat tested from the concentrate treatments compared to the ryegrass treatments. These findings indicate that the fattening of lambs on improved pastures or a concentrate-based diet prior to slaughter may alter meat characteristics.
Forfattere
Vibeke Lind Jan Berg Lars Olav Eik Jørgen A.B. Mølmann Espen Haugland Marit Jørgensen Margrethe HerslethSammendrag
Many consumers perceive lamb meat from mountain pastures to be of superior quality, a quality that may be altered if lambs are kept for a longer period on cultivated pastures before slaughtering. The objective of this experiment was to compare sensory profile and fatty acid composition in meat from lambs slaughtered directly from unimproved mountain pastures with meat from lambs raised on unimproved mountain pastures and fattened on biodiverse cultivated pastures for 26, 39 and 42 days before slaughtering. The experiment was conducted at two different locations in Norway in 2006 and 2007, with a total of 124 Norwegian Crossbred Sheep lambs. Loin samples of M. Longissimus dorsi from lambs above a body weight of 40 kg were selected and analysed for sensory attributes. Fatty acid composition was determined in the subcutaneous fat over the Longissimus dorsi. Small but significant differences were found in hardness, tenderness, fattiness, metallic and rancid flavour, and in polyunsaturated fatty acids. This indicates that to a small extent pre-slaughter fattening on cultivated pastures alters meat characteristics. (C) 2009 Elsevier Ltd. All rights reserved.
Sammendrag
Det er ikke registrert sammendrag