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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.

2017

Abstract

Red clover (Trifolium pratense L.) is normally a short-lived perennial with no vegetative propagation and the number of plants in the field declines rapidly. In organic farming, the amount of clover in the field is decisive for the N2 fixation and yield, the protein content and quality of the forage produced. In Nordland County (66.27°N), there is a farm with some red clover plants in more than 15 years old grassland. In the presented study we examined grassland botanical content and attempted to recognise age of red clover plants. Our hypotheses was 1) that extensive grassland management promotes self-seeding of red clover 2) self-seeding maintaining a desired content of red clover over time. In addition, we tested two harvesting regimes of the first cut for seed maturation and seed quality at two locations in Norway. Red clover plants in old swards showed very high age and a branched root system. Only very few seedlings were found in old sward suggesting that self-seeding was insignificant. Experiments with leaving the grassland after the first cut for seed production of clover failed due to poor seed maturation. Surface seeding of red clover in pure grass plots gave good results, especially with early spring seeding.

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Abstract

Insulation is an essential component of nest structure that helps provide incubation requirements for birds. Many species of waterfowl breed in high latitudes where rapid heat loss can necessitate a high energetic input from parents and use down feathers to line their nests. Common eider Somateria mollissima nest down has exceptional insulating properties but the microstructural mechanisms behind the feather properties have not been thoroughly examined. Here, we hypothesized that insulating properties of nest down are correlated to down feather (plumule) microstructure. We tested the thermal efficiency (fill power) and cohesion of plumules from nests of two Icelandic colonies of wild common eiders and compared them to properties of plumules of wild greylag goose Anser anser. We then used electron microscopy to examine the morphological basis of feather insulating properties. We found that greylag goose down has higher fill power (i.e. traps more air) but much lower cohesion (i.e. less prone to stick together) compared to common eider down. ese differences were related to interspecific variation in feather microstructure. Down cohesion increased with the number of barbule microstructures (prongs) that create strong points of contact among feathers. Eider down feathers also had longer barbules than greylag goose down feathers, likely increasing their air-trapping capacity. Feather properties of these two species might reflect the demands of their contrasting evolutionary history. In greylag goose, a temperate, terrestrial species, plumule microstructure may optimize heat trapping. In common eiders, a diving duck that nests in arctic and subarctic waters, plumule structure may have evolved to maximize cohesion over thermal insulation, which would both reduce buoyancy during their foraging dives and enable nest down to withstand strong arctic winds.

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Abstract

Denne rapporten oppsummerer resultatene fra er treårig forskningsprosjekt vedrørende den unike ærfuglduna. Dunprøver fra 19 kolonier i fire ulike land ble renset på en standardisert måte og ulike parametere ble målt og testet som fill power, sammenhengskraft og resiliens. Det ble dokumentert variasjon i ulike parametere både mellom kolonier og mellom individer. Dette er den største og mest dyptgående studien av ærfugldun som har blitt utført. This report sums up the result from a three-year lasting study regarding the unique eider down. Eider down from 19 colonies was collected and we measured various parameters such as fill power,cohesion and resilience. Overall, this is the largest and most in-depth study of eider down ever performed.

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Abstract

Two field trials with five strawberry cultivars planted on a woven black polyfibre ground cover sheet with or without translucent sheet plant coverage during winter and the growing season as combined treatments were started in 2004 and 2005. In total, nine different cultivars were included in the two fields. One early cv. ‘Polka’ and one late cv. ‘Korona’ acted as standard cultivars, while the other cultivars were new, named or labelled selections from Norwegian, Finnish and Swedish breeding programs. Winter survival, spring vigour, earliness, saleable and total berry yield, berry size and berry quality were registered for three years. The cultivars differed in earliness, berry size, yield (gram per plant) and total production (sum of all years). A combination of fibre sheet winter and spring coverage and more open net sheet harvest season coverage showed favourable results for overwintering, earliness and berry yield, and enhanced the ripening process in all cultivars.

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Abstract

Anthocyanins are the main pigments in the Vaccinium berries. Besides contributing to the characteristic bluish to reddish colors of the berries, anthocyanins are also recognized as potential health beneficial compounds. The biosynthesis of anthocyanins is well understood and the key regulators have been characterized in many plant species. The final anthocyanin composition in ripe berries is regulated by developmental and environmental factors, determined by the genetic background. We have studied the role of different light and temperature conditions on the accumulation of anthocyanins in wild bilberry (V. myrtillus L.) and cultivated highbush blueberry (V. corymbosum L.), in controlled and in field experiments. These experiments include specific growth conditions with clones from northern and southern latitudes as well as from different altitudes. The results show speciesspecific interactions in quantitative and qualitative composition of anthocyanins as a response to light and temperature conditions. For instance, lower temperature and specific light wavelengths induced accumulation of delphinidin glycosides in bilberry.

Abstract

The industrial demand for wax is about 1.000.000 tons annually from which about only 3% is covered by natural waxes and 97% (mainly as paraffin) is produced from non-renewable (mainly fossil) sources. The total market value for this market is about 600-700 M€ per year. Compared to synthetic waxes which are fossil (oil) based and chemically processed materials, the natural waxes are produced by biogenesis, renewable and thus contribute to sustainable processes and reduced carbon emission. Also, natural waxes show well-balanced composition and perform in many applications much better than their synthetic counterparts. In Scandinavia we have very interesting candidates for domestic wax production i.e. wild berries such as lingonberry (Vaccinium vitis-idae L.) and bilberry (Vaccinium myrtillus L.) are abundantly found and important industrially utilized wild berries in arctic nature but we have also other interesting species like black crowberry (Empetrum nigrum) and bog bilberry (Vaccinium uliginosum). Wild berries are used increasingly by food industry due to their reported health and probiotic effects but much of the resource material is wasted as side stream after the food processing. In this project we want to develop methods for exploiting the raw material still present in the side stream and thus increasing its value. The broad expertise areas of the researchers involved covering biology, technology and marketing offer excellent background for the present project. The results achieved will be presented in the meeting. The project is funded by Interreg Nord.

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Abstract

Climate change and its effects on grassland productivity vary across Europe. The Mediterranean and Nordic regions represent the opposite ends of a gradient of changes in temperature and precipitation patterns, with increasingly warmer and wetter winters in the north and increasingly warmer and drier summers in the south. Warming and elevated concentration of atmospheric CO2 may boost forage production in the Nordic region. Production in many Mediterranean areas is likely to become even more challenged by drought in the future, but elevated CO2 can to some extent alleviate drought limitation on photosynthesis and growth. In both regions, climate change will affect forage quality and lead to modifications of the annual productivity cycles, with an extended growing season in the Nordic region and a shift towards winter in the Mediterranean region. This will require adaptations in defoliation and fertilization strategies. The identity of species and mixtures with optimal performance is likely to shift somewhat in response to altered climate and management systems. It is argued that breeding of grassland species should aim to (i) improve plant strategies to cope with relevant abiotic stresses and (ii) optimize growth and phenology to new seasonal variation, and that plant diversity at all levels is a good adaptation strategy.