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
Le gel printanier peut etre dommageable pour les semis de Picea abies (L.) Karst. nouvellement plantes si leur rythme de croissance n'est pas suffisamment adapte aux conditions climatiques de la station forestiere. Les objectifs de cette etude consistaient a determiner de quelle facon le debourrement et la resistance au gel printanier sont influences par un traitement de jours courts (JC) appliques a differents moments et avec differents regimes de temperature durant la periode de formation des bourgeons. A la suite d'un entreposage hivernal, la resistance au gel a ete evaluee apres une, trois et cinq semaines dans des conditions de forcage. Le traitement JC a avance le debourrement comparativement aux semis temoins. Par comparaison, le moment du traitement et les differentes temperatures ont eu peu d'effet sur le debourrement. Le traitement JC a augmente la resistance au gel des aiguilles d'un an pendant la periode de desendurcissement. Applique tot, le traitement JC a augmente la resistance au gel des aiguilles d'un an et le diametre au collet comparativement a une application plus tardive. Il est important que la periode de noirceur atteigne une duree critique lorsque le traitement JC prend fin pour eviter une deuxieme eclosion des bourgeons. Des temperatures basses a la suite du traitement JC ont augmente la resistance au gel des aiguilles et diminue celle de la tige. Les effets contraires de la temperature sur differents tissus vegetaux demontrent l'importance d'examiner differents tissus apres des essais de gel-degel. Spring frost may result in detrimental damage in newly planted Picea abies (L.) Karst. seedlings if their growth rhythm is not sufficiently adapted to the climatic conditions on the forest site. The aims of this study were to evaluate how bud break and spring frost hardiness were influenced by short-day (SD) treatments with different timing and different temperature regimes during bud formation. Following winter storage, frost hardiness was tested after 1, 3 and 5 weeks in forcing conditions. The SD treatment advanced bud break compared with the control seedlings. In comparison, the effects of timing and the different temperatures on bud break were small. The SD treatment improved frost hardiness in first-year needles during dehardening. The early SD treatment resulted in improved frost hardiness in first-year needles and greater root collar diameter compared with later SD treatment. To avoid a second bud flush, it is important that a critical night length is attained when the SD treatment terminates. Low temperatures following the SD treatment resulted in increased hardiness of the needles and decreased hardiness of the stems. The contrasting effect of temperature in different plant tissues demonstrates the importance of examining different tissues following freezing tests.
Abstract
Dormancy release as influenced by duration of outdoor winter chilling in Florence (Italy) was studied under different photoperiodic and temperature treatments in collected twigs of two European (Ulmus glabra Huds. and Ulmus minor Mill.) and four Asian (Ulmus pumila L., Ulmus parvifolia Jacq., Ulmus macrocarpa Hance and Ulmus villosa Brandis) elm clones. Photoperiod had no effect on dormancy release, and there was no evidence that photoperiod affected bud burst during quiescence in the studied elm clones. Thermal time (day degrees >0 °C) to bud burst decreased in all the clones with increasing outdoor chilling. Although all the clones exhibited a rather weak dormancy, they significantly differed from each other. Dormancy was released earlier in the Asian than in the European clones, and the clones could be ranked from the U. pumila clone (very weak and short dormancy) to the U. minor clone (relatively stronger and longer dormancy), the other clones being intermediate. In all the clones except U. minor, the observed decrement in thermal time to bud burst was efficiently explained as an inverse exponential function of the number of chill days ≤5 °C received outdoor in autumn and winter. Endodormancy, as measured by the single-node cuttings test, was weak and short in all the clones. The latter result suggests that correlative inhibitions were largely responsible for preventing bud burst during winter in these elm clones.
Authors
Harald Bratli Per Magnus Jørgensen Reidar Haugan John Inge JohnsenAbstract
Catapyrenium psoromoides has been discovered in three localities in southern Norway, in Aust-Agder (Åmli), Hedmark (Ringsaker) and Rogaland (Rennesøy). In Aust-Agder and Rogaland it occurred on Ulmus glabra in a wood pasture and an open deciduous forest. In Hedmark the species was found on a calcareous rock outcrop. These finds fill in the distribution gap between Scotland and Sweden and confirm that the species is nemoral to southern boreal with oceanic tendencies. The preference for big, broad-leaved trees in the Atlantic-Mediterranean part of the distribution area is pointed out.
Authors
Harald Bratli Per Magnus Jørgensen Reidar Haugan John Inge JohnsenAbstract
No abstract has been registered
Authors
Rolf Rødven Rolf Anker Ims Nigel YoccozAbstract
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Authors
Carola Strassner Melanie Lukas Anne-Kristin LøesAbstract
In the iPOPY project (innovative Public Organic food Procurement for Youth), one of the tasks was to map the challenges linked to the supply chains of organic food, and to which extent the participating countries have developed any form of certification of out-of-home food serving. For primary production and processing, regulations have been developed on the EU level. Norway, as a member of the EEA, is obliged to follow these EU regulations. However, the EU regulations on organic agriculture do not comprise catering, restaurants and other out-of-home food service. Hence, various countries have developed different systems to certify e.g. restaurants wanting to market their organic menus. This report describes the systems in Denmark, Finland, Italy, Norway and Germany. Germany has been used as a reference, since this country is especially familiar to the first author of the report, Dr. Carola Strassner, due to former work and analyses. The report is based on information acquired from certification bodies and experts in each country by questionnaires communicated via e-mail, and subsequent telephone interviews.
Authors
Anne Moxnes Jervell Asbjørn VeidalAbstract
No abstract has been registered
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Abstract
Modification of wood with furfuryl alcohol or furfuryl alcohol prepolymer leads to a wood product with increased decay resistance, hardness and dimensional stability. In normal application, i.e. under Use Class 3 conditions, furfurylated wood can be regarded as non-toxic. This has earlier been demonstrated by toxic hazard tests on water leachates using relevant leaching procedures, e.g. the OECD Guideline 313 or the Dutch shower test procedure. These leachates showed slight to no toxicity towards standard aquatic test organisms. However, when using forced leaching procedures with limited amount of water such as the EN 84 procedure, slight to moderate toxicity to the same test organisms was observed, depending on furfurylation process. Furthermore, earlier studies have shown that leachates from wood treated with furfuryl alcohol pre-polymers have higher toxicity to Vibrio fischeri (luminescent marine bacterium) than leachates from wood treated with furfuryl alcohol monomers and that this probably is attributed to differences in leaching of chemical compounds. The ambition of the present study, was to investigate which chemical compounds in the leachates causes toxicity to the aquatic organisms V. fischeri and Daphnia magna (water flea). In this study five different wood species, both hardwoods and softwoods, treated with three different furfurylation processes, were leached according to two different leaching methods. The study shows that this difference in toxicity of leachates towards V. fischeri most likely cannot be attributed to maleic acid, furan, furfural, furfuryl alcohol or 2-furoic acid. However, the difference in toxicity might be caused by the substance 2,5-furandimethanol. Leachates from furfurylated wood still need to be investigated further in order to identify the chemical differences between wood furfurylated with furfuryl alcohol monomers and furfuryl alcohol prepolymer causing differences in toxicity to different organisms.