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.
2009
Authors
Vibeke Lind Jan Berg Lars Olav Eik Jørgen A.B. Mølmann Espen Haugland Marit Jørgensen Margrethe HerslethAbstract
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.
Abstract
In this study we aimed at understanding the mechanisms that affects an epidemic development of Neozygites floridana in a Tetranychus urticae population. This was done by comparing how many spores a cadaver infected with a N. floridana isolate could produce and at what distance and in which directions they could be thrown on a coverslip at temperatures relevant to the northern hemisphere (13, 18 and 23oC). The highest number of spores were produced at 13oC at a number of 1886. Numbers of spores thrown at 18oC and 23oC were 1733 and 1302 respectively. Temperature had a significant effect on sporulation. Most of the spores were thrown at a distance of 0-0.6 mm from the cadaver. Cadavers placed on the underside of a coverslip were able to throw spores back up on the coverslip surface. A whole plant bioassay was also conducted to reveal where on a plant T. urticae infected with N. floridana die and sporulate. Cadavers showed a different verical distribution on the cucumber plant compared to healthy spider mites. Most of the cadavers were located at the lower to the middle part of the plant, while healthy spider mites were more evenly distributed on the whole plant.
Authors
Kristine Solberg Rolf David Vogt Odd EilertsenAbstract
No abstract has been registered
Authors
Igor A. Yakovlev Harald Kvaalen Carl Gunnar Fossdal Øystein JohnsenAbstract
MicroRNAs (miRNAs) are endogenous small RNAs that can have large-scale regulatory effect and could participate in epigenetic regulation of gene expression in plants. We show for the first time that temperature during zygotic embryogenesis and seed maturation in Norway spruce regulates an “epigenetic memory” in the progeny, regenerated through somatic embryogenesis. The warmer the in vitro temperature applied, the later the regenerated plants formed terminal buds in the common environment the second growth season. The differences were very large, and similar in size to a provenance separation of 4 – 6 degrees of latitude (Kvaalen and Johnsen, 2008). To study a molecular mechanisms of a memory from embryo development we have prepared two concatemerized small RNA libraries representing small RNAs predominantly expressed in plants growing from seeds obtained after embryogenesis in cold environment (CEL) and warm environment (WEL) after short day (SD) treatment (going to bud set). In total we obtained 201 different small RNAs, with dominated length of 21-nt, 123 from WEL and 93 from CEL. Using multiple methods, including BLAST, sequence alignment and sequence folding we found 27 novel candidate miRNAs and only 3 earlier described. Additionally 103 small RNAs have exact matches in spruce EST database, which could be their putative targets and 67 small RNAs have no matches. We used quantitative RT–PCR to study the expression patterns of 31 chosen candidate miRNAs and monitor the occurrence stage-dependent miRNA-mediated cleavage for 4 regions of putative mRNA targets. All miRNA show difference in transcript levels after SD treatment and 12 miRNAs show constitutively differential expression in progeny from CE and WE. Kvaalen H, Johnsen O (2008) Timing of bud set in Picea abies is regulated by a memory of temperature during zygotic and somatic embryogenesis. New Phytologist 177: 49-59
Authors
Jarl-Gunnar Salin Peder GjerdrumAbstract
Wooden poles are frequently used for power and telecommunication lines. After creosote preservation the durability is secured for many decades. This study is related to a Norwegian plant where such poles are produced using Scots pine. Prior to the preservation process the poles have to be dried to a moisture content below the fibre saturation point everywhere in the pole. This is done outdoors in open stacks of poles, i.e. as air-drying. A problem is caused by the difficulties to determine when the target moisture content has been reached. The inventory of drying poles represents considerable value in a company\"s balance sheet and risk of downgrading. Knowledge of drying times during the annual seasons has been insufficient, and no efficient method is known for accurately observing the MC through the various parts of the poles.....
Abstract
No abstract has been registered
Abstract
Evaluation of climate change consequences and national carbon reporting such as under the Kyoto protocol require long-term monitoring of carbon fluxes. We report on an ongoing project aimed at a national-level assessment of the terrestrial carbon sequestration potential under present conditions and under various climate and land use change scenarios, in particular in terms of their temperature effect. We develop empirical models for national soil carbon stock assessment and evaluate process-based soil carbon models for prediction of future carbon dynamics.....
Authors
Håkon BorchAbstract
This poster presents a new low cost model for modelleing phosphorus and soil loss from agriculture land, and to do evaluation of different mitigation scenarios where the cost effectiveness of the meassures influence each other. The model has been used in several Norwegian catchments to evaluate mitigation options, and to build packages of measures to comply with the demands from the European Water Framework Directive.
Authors
Aksel DøvingAbstract
No abstract has been registered
Authors
Ole Martin Bollandsås Ingvild Rekstad Erik Næsset Ingvald RøsbergAbstract
The objectives of this study were (1) to develop models for estimation of total above-ground biomass, tree crown biomass and stem biomass of mountain birch (Betula pubescens spp. czerepanovii), and (2) to test the stability of the relationships between biomass and biophysical tree properties across geographical regions and tree size ranges. The models were developed using a mixed modelling approach accounting for the hierarchical structure of the data that originated from sample plots. Diameter at breast height, tree height, and the ratio between height and diameter were candidate explanatory variables, but only diameter was statistically significant (p0.05). The model fit values (pseudo-R 2) were 0.91, 0.60 and 0.85 for the three respective models. A substantial part of the model random errors could be attributed to between-plot variations. The conclusion related to objective (1) was that the models are well suited for biomass prediction of mountain birch in the mountain areas of southern Norway. Furthermore, models reported in previous research that had been calibrated on data from other regions were applied on the current data set. The results indicate that models calibrated for small trees produced predictions diverging from the observed values of the current data set. The differences between predicted and observed values also seem to vary along a site productivity gradient. Still, even though the differences between predicted and observed values using the different models varied quite a lot, the relationships were relatively stable within certain limits. The conclusion related to objective (2) was that biomass models can be applied outside the region for which they were developed, which in many cases is necessary because local models do not exist. However, the properties of the model development data related to tree size range and site productivity should be similar to those of the area for which predictions are being made.