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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.

2010

Abstract

Norway spruce (Picea abies L. Karst) and Siberian spruce (Picea obovata Lebed.) are closely related and occupy a large parapatric area across the entire northern Eurasia. They have been suggested to be connected by a wide zone of hybridization along the Ural Mountains, separating the European Norway spruce from the Siberian spruce. This introgressive zone is believed to be formed by secondary contact after the last glaciation. Based on macrofossils, P. obovata has been suggested to have survived the LGM in refugia both on the eastern and the western side of the Urals. Previous genetic isozyme studies have indicated that the two spruce taxa are genetically poorly differentiated.

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Abstract

The blue-stain fungus Ceratocystis resinifera colonizes wounds on living Picea spp. and other conifers in Europe and North America. Little is known regarding the pathogenicity of this fungus and consequently, four Norwegian C. resinifera isolates were inoculated on to Norway spruce (Picea abies) using two different techniques. These included single-point inoculations on young trees (two inoculations per tree on 14-year-old trees) and mass-inoculations on older trees (∼200 inoculations per tree on 34-year-old trees). In both experiments, C. resinifera induced minor symptoms that in most cases did not differ significantly from inoculation with sterile agar. The virulent blue-stain fungus C. polonica, which was inoculated for comparative purposes, induced extensive symptoms, causing 83% dead cambium circumference and 82% blue-stained sapwood, and long necrotic lesions in the phloem. The results suggest that C. resinifera is non-pathogenic or only mildly pathogenic to Norway spruce and does not present a threat to these trees.

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Abstract

The purpose of this study was to compare the effect of grazing on mountain (M) versus cultivated lowland pasture (C) on the performance and meat quality of suckling calves (Experiments 1 and 2). In addition, the effect of finishing on C after M on growth and meat quality was assessed (Experiment 2). Animals on C and M had on average similar live weight gain and carcass weight in the first experiment. However, the performance depended on year as gain and carcass weight was higher on C than on M in the first year and vice versa in the second year. In the second experiment the calves on M had lower gain and carcass weight than on C. Three weeks finishing on C after M compensated to some extent for the lower growth rate on M. Overall, the results indicate that mountain grazing may yield similar growth rates and slaughter weights as improved lowland pasture depending on year. There were only small effects of pasture type on carcass and meat quality traits like conformation, fatness, intramuscular fat and protein content, and fatty acid (FA) composition. The variation in FA composition could to a large extent be explained by difference in fatness with increase in monounsaturated and decrease in polyunsaturated FA with increasing intramuscular fat content, in turn varying between pasture type, experiment and year. There was a tendency that M led to higher proportion of C18:1n-9 and lower proportion of C18:1n-7 than C. which may be due to difference in milk and forage intake. Both pasture types resulted in meat with intramuscular fat with high nutritional value since the n-6/n-3 ratio was low. (C) 2010 Elsevier B.V. All rights reserved.

Abstract

One of the main challenges for new wood protection systems is to predict in a fast and accurate way service life in use class 3 (above ground) and use class 4 (in soil or fresh water contact). New environmentally benign wood protection systems are expected to have different modes of action against wood deteriorating fungi compared to the traditional preservatives, change in water sorption being one of them. Therefore it is of importance to evaluate new treated wood products in a broad range of exposure situations, also exploring the variation within use class 3 and 4. Due to the restrictions in the use of chromium containing wood preservatives, a range of studies have been published the last decade evaluating the performance of new products after laboratory or field test exposure. However, there is still a lack of studies comparing the same material in different field exposure situations. This study evaluates the efficacy of 13 novel wood protecting systems in three different above ground tests (horizontal double layer, block test and mini stakes) and two different in-ground tests (EN 252 and mini stakes). Scots pine (Pinus sylvestris L.) sapwood from the same wood source was used for all treatments. For each wood protecting system the wood specimens for all five tests were treated together in the same batch. The results after five years of field exposure are presented. In the three above ground tests no or only initial signs of decay were detected after five years (not reaching a mean rating of 1). The decay rate in soil contact was faster than above ground, but after five years only untreated wood (controls) failed in both tests. No significant difference in performance was found between the two tests in soil contact. The use of median decay rate values gave an earlier indication of performance than the use of mean decay rate values.