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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.

2016

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Schistidium marginale is described as a new species from several European states including Austria, Georgia, Italy, Macedonia, Spain, Switzerland and Turkey. The species is fully illustrated, its affinities are discussed in detail and its current distribution is mapped. The new species is closely related to S. confertum and S. echinatum from which it differs in having a coarser and thicker costa which is 3–4-stratose in mid-leaf and 4-layered at the base; strongly thickened, 2–4-stratose and (1–)2–5-seriate leaf margins; and a thicker and stiffer leaf hair-point. It clearly belongs to Schistidium Bruch & Schimp. sect. Conferta (Vilh.) Ochyra on account of the distinct 3–6(–7)-seriate basal marginal border of quadrate to short-rectangular, often subhyaline cells with distinctly thickened transverse walls.

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The aim of cell wall modification is to keep wood moisture content (MC) below favorable conditions for decay organisms. However, thermally modified, furfurylated, and acetylated woods partly show higher MCs than untreated wood in outdoor exposure. The open question is to which extent decay is influenced by the presence of liquid water in cell lumens. The present paper contributes to this topic and reports on physiological threshold values for wood decay fungi with respect to modified wood. In total, 4200 specimens made from acetylated, furfurylated, and thermally modified beech wood (Fagus sylvatica L.) and Scots pine sapwood (sW) (Pinus sylvestris L.) were exposed to Coniophora puteana and Trametes versicolor. Piles consisting of 50 small specimens were incubated above malt agar in Erlenmeyer flasks for 16 weeks. In general, pile upward mass loss (ML) and MC decreased. Threshold values for fungal growth and decay (ML ≥ 2%) were determined. In summary, the minimum MC for fungal decay was slightly below fiber saturation point of the majority of the untreated and differently modified materials. Surprisingly, T. versicolor was able to degrade untreated beech wood at a minimum of 15% MC, and growth was possible at 13% MC. By contrast, untreated pine sW was not decayed by C. puteana at less than 29% MC.

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Growth of dark moulds enables the use of a decorative and protective biofinish for wood, showing advantages compared to traditional wood-coatings in terms of sustainability and selfrepair. Based on the formation of a uniform mould covering on oil treated wood during outdoor exposure, the utilisation of a biofinish is in development. Basic information is lacking on the correlation between exposure site and biofinish formation on wood. To evaluate the impact of different locations, a biofinish assessment method was applied on different combinations of wood species and vegetable oil types after outdoor exposure in the Netherlands and Norway. Biofinishes were detected on wood samples made of spruce, pine sapwood and ilomba that were treated with olive oil and on pine sapwood treated with raw linseed oil after one and a half year of outdoor exposure in the Netherlands. More time was needed for biofinish formation on multiple wood-oil combinations for samples exposed in Norway. After two years of outdoor exposure three out of five wood-oil combinations that contained biofinishes in the Netherlands, showed similar results with the samples in Norway. Biofinish formation was not detected at all on untreated wood samples, regardless the wood species or exposure site. Loose fibres were observed on the surface of all untreated samples. It is likely that biofinish formation was prevented by the removal of stained fibres. Analysis of the stain coverage development on the wood samples, including initial stages of biofinish formation, showed a significant effect of exposure time and (oil) treatment on the stain coverage.

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We demonstrate the efficacy of using close-range photogrammetry from a consumer grade camera as a tool in generating high-resolution, three-dimensional coloured point clouds for detailed analysis or monitoring of wheel ruts. Ground-based timber harvesting results in vehicle traffic on 12–70 per cent of the site, depending on the system used, with a variable probability of causing detrimental soil disturbance depending on climatic, hydrological and soil conditions at the time of harvest. Applying the technique described in this article can reduce the workload associated with the conventional manual measurement of wheel ruts, while providing a greatly enhanced source of information that can be used in analysing both physical and biological impact, or stored in a repository for later operation management or monitoring. Approaches for deriving and quantifying properties such as rut depths and soil displacement volumes are also presented. In evaluating the potential for widespread adoption of the method among forest or environmental managers, the study also presents the workflow and provides a comparison of the ease of use and quality of the results obtained from one commercial and two open source image processing software packages. Results from a case study showed no significant difference between packages on point cloud quality in terms of model distortion. Comparison of photogrammetric profiles against profiles measured manually resulted in root mean square errors of between 2.07 and 3.84 cm for five selected road profiles. Maximal wheel rut depth for three different models were 1.15, 0.99 and 1.01 m, and estimated rut volumes were 9.84, 9.10 and 9.09 m3, respectively, for 22.5 m long sections.

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Hypericum perforatum L. is an important medicinal plant for the treatment of depression. The plant contains bioactive hypericins that accumulate in dark glands present especially in reproductive parts of the plant. In this study, pathogenesis-related class 10 (PR-10) family genes were identified in H. perforatum, including three previously unidentified members with sequence homology to hyp-1, a phenolic coupling protein that has earlier been suggested to participate in biosynthesis and binding/transportation of hypericin. The PR-10 genes showed constitutive but variable expression patterns in different H. perforatum tissues. They were all expressed at relatively high levels in leaves, variably in roots and low levels in stem and reproductive parts of the plant with no specific association with dark glands. The gene expression was up-regulated in leaves after salicylic acid, abscisic acid and wounding treatments but with variable levels. To study exact location of the gene expression, in situ hybridization of hyp-1 transcripts was performed and the accumulation of the Hyp-1 protein was examined in various tissues. The presence of Hyp-1 protein in H. perforatum tissues mostly paralleled with the mRNA levels. In situ RNA hybridization localized the hyp-1 transcripts predominantly in vascular tissues in root and stem, while in leaf the mRNA levels were high also in mesophyll cells in addition to vasculature. Our results indicate that the studied PR-10 genes are likely to contribute to the defense responses in H. perforatum. Furthermore, despite the location of the hyp-1 transcripts in vasculature, no support for the transportation of the Hyp-1 protein to dark glands was found in the current study. The present results together with earlier data question the role of the hyp-1 as a key gene responsible for the hypericin biosynthesis in dark glands of H. perforatum.

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The aim of this study was to evaluate the effect of conventional versus organic common bean (Phaseolus vulgaris) production on natural occurrence of Beauveria spp. as entophytes in bean plant tissue, from soil and as infections in stink bugs (Hemiptera: Pentatomidae), an important pest of bean in Cuba. Twenty-four organic and conventionally managed bean fields were sampled from September 2014 to April 2015 and Beauveria spp. were isolated and DNA extracted. PCR amplification of the intergenic Bloc region was performed for the identification of Beauveria species. Eighty-seven isolates were obtained from the soil samples by using the Galleria mellonella baiting technique. Further, 45 isolates were obtained from endophytic tissues of bean plant parts and 18 isolates were acquired from stink bugs. Only Beauveria bassiana was identified by DNA sequencing in this material. B. bassiana was more prevalent in soil, plant and stink bugs sampled from organic fields (41% soil, 22% plant, 9% bugs) compared to conventional fields (17% soil, 8% plant, 2% bugs). All plant parts were colonized by B. bassiana, but a significantly higher occurrence of this fungus was found in roots (9%) compared to stems (6%), leaves (4%) and pods (2%) in organic fields. In conventional fields there was a significantly higher occurrence of B. bassiana acquired from root (4%) and stem (3%) compared to leaves (1%) and pods (1%). Mating type PCR assays revealed that each of the isolates carried single mating types, with frequencies of 146/150 (MAT1) and 4/150 (MAT2), indicating limited potential for recombination. Our findings show that B. bassiana occur naturally as endophytes in bean fields in Cuba and contribute to a better ecological understanding of B. bassiana in agriculture.

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Disease-suppressive effects of nighttime applications of ultraviolet-B (UV-B) were investigated at two irradiance levels (1.6 or 0.8 W/m2) in strawberry and rosemary plants inoculated with Podosphaera aphanis or Golovinomyces biocellatus, respectively. Plants were exposed to each irradiance level every third night for either 9 or 18 min, every night for either 3 or 6 min, or three times every night for either 1 or 2 min. Thus, over time, all plants received the same cumulative dose of UV-B, and severity of powdery mildew was reduced by 90 to 99% compared with untreated controls in both crops. Use of polished aluminum lamp reflectors and UV-B reflective surfaces on greenhouse benches significantly increased treatment efficacy. An automated apparatus consisting of an adjustable boom with directed airflow was used to move UV-B lamps over greenhouse benches at 25 or 50 cm/min. Directed airflow moved leaves on the subtending plants to better expose upper and lower surfaces to UV-B but directed airflow actually decreased the efficacy of UV-B treatments, possibly by dispersing conidia from lesions before they were exposed to a lethal dose of UV-B. Results indicate broad applicability of nighttime applications of UV-B to suppress powdery mildews, and that cumulative UV-B dose is an overriding factor determining efficacy. Finally, enhanced suppression on shaded or obscured tissues is more likely to be affected by reflective bench surfaces than through attempts to physically manipulate the foliage.

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This study analyzes TTIP, its implications for Norway and Norway’s trade policy choices. TTIP will hardly be concluded under Obama's presidency, but the agreement could become a reality within a few years. TTIP aims at comprehensive cooperation in the regulatory area. In the short term there will be limited harmonization of standards but regulatory cooperation between different systems. In the long term, the goal is stronger cooperation in the regulatory area. TTIP will from what we know not lead to a lowering of European health regulations or a "race to the bottom". If TTIP is realized and Norway remains outside, the EEA Agreement will be little affected and the overall economic impact is moderate. If Norway joins TTIP, there will be a significant real income gain, with estimates ranging from 2236 to 6772 NOK per capita in the various scenarios. There is considerable variation across sectors. With Norway outside TTIP there will be a moderate negative impact for a majority of the sectors, especially some manufacturing sectors that face tougher competition in the EU and USA export markets. The oil industry will benefit from increased demand and higher prices. If Norway joins TTIP, a clear majority of industries will benefit; especially business services and a number of other service industries. The public sector gains from TTIP, mainly due to cheaper inputs. TTIP will contribute to the dismantling of import protection for Norwegian agriculture and without compensating measures, production and employment will be reduced. TTIP will still allow some import protection and this margin of maneuver, which depends on future negotiations, is important for the outcome. With a larger margin of manoeuvre and unchanged budgetarty support, most of Norway’s agriculture can be maintained. With less margin of manoeuvre, it will be more challenging. Norwegian accession to TTIP may occur in the form of a standard trade agreement in which Norway or EFTA are formally equal to the EU and the United States. Alternatively, Norway may participate in a European pillar as in today's "Open Skies" agreement on air traffic. If TTIP succeeds in establishing comprehensive regulatory cooperation, the latter solution is most likely. Such a solution implies that Norway will become more closely integrated with the European Union also in trade policy towards third countries. Norwegian entry into TTIP implies that we have to accept the established rules and negotiate bilaterally with the EU and the USA on market access. The negotiations with the USA will apply to all aspects of market access, while negotiations with the EU will apply only to areas in which the EEA agreement is not already deeper. The negotiations with the EU for TTIP entry will thus include, among other issues, tariffs for seafood and agriculture. As an alternative to membership in TTIP, Norway or EFTA may initiate a trade agreement with the USA. Such an agreement would likely be less extensive in the regulatory area. Such an agreement will also provide an economic gain for Norway, but less than accession to TTIP. For Norway as a whole, accession to TTIP creates a real income gain between 12.5 and 35 billion NOK according to various scenarios, while a free trade agreement with the United States results in a gain of about 7.4 billion NOK. TTIP also includes negotiations on so-called Investor-State Dispute Settlement (ISDS), whereby foreign-owned companies can sue a state if they are unfairly or inappropriately treated. Such rights also exist in national law but international tribunals have to some extent extended the interpretation of what is considered unfair. The European Union has proposed a solution in TTIP with a permanent court as well as rules that discipline the interpretation of the principles, and thus avoids that ISDS unduly interferes into the states’ "right to regulate". This and many other issues are analysed in this report and six background papers.