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.
2007
Abstract
No abstract has been registered
Academic – Stochastic utility-efficient programming of organic dairy farms
Ola Flaten, Gudbrand Lien
Abstract
No abstract has been registered
Authors
Arnstein Staverløkk May SæthreAbstract
Dispersal of alien species, plant pests and other organisms through trade with living plants and plant parts increases with globalisation. Every year a significant amount of horticultural plants for use in urban landscapes and private gardens are imported to Norway from several other European countries. The last decade the amount of such import to Norway has doubled, while the resources allocated for phytosanitary control of this goods on arrival has not had a similar development. Trees and bushes for outdoor use pose a special risk for carrying unwanted stowaways since they are mostly produced outdoors in the export country and are in addition frequently exported with a lump of soil from the production site. After arrival in Norway the plants are dispersed quickly to all parts of the country where they are sold to private and official buyers. The quick handling of this material makes it easy for an organism to stay alive and have the opportunity to establish in the new environment. A study was carried out in 2006 to aiming to find out more about this trade, particularly emphasizing on identifying species of insects and arachnids that were suspected to pass through the national control system. Mattilsynet, the Norwegian Food Safety Authority, is the National Plant Protection Organization of Norway, and perform random sampling of imported plant commodities of this type. Unfortunately, there is practically no surveillance on the introduction of species that are not on the quarantine pest list, and the standard control routines fail in detecting and rejecting plant commodities that contain non-quarantine species. In this study it was mainly searched for insects and arachnids, but snails and slugs, millipedes and other organisms were also found. The plant species sampled were mostly conifers, of which Thuja sp. and Taxus sp. were the majority. Conifers turned out to be excellent in providing shelter and hiding places for small organisms. Three sampling methods were used: 1. Shaking method, 2. Visual observation and 3. Sampling of the compost fallen off the consignments during the transport. The last method added most species to the list. In only six samples of compost investigated as much as 93 different species were identified. During a short period of sampling 1193 individuals were collected travelling as stowaways mainly from Germany, Denmark and the Netherlands. 156 species were identified and additional 26 organisms were identified to the genus level.
Authors
Lars T. HavstadAbstract
Different methods of straw residue management were evaluated in field trials with seed crops of timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis Huds.) in SE Norway during 2000-2005. Compared to straw removal, which up to now has been the most common straw management practice in seed production of the two species, straw chopping and spreading at the back of the combiner during seed harvest did not reduce seed yield in the following year when stubble height was kept at a low level (preferably less than 10 cm). However, in order for newly developed tillers to rapidly penetrate the straw layer in autumn, the chopped straw had to be spread uniformly in the field. The experiments did not provide any support for an extra input of nitrogen in autumn, either in timothy or meadow fescue, when the straw was chopped rather than removed. In both species, also burning of straw and stubble soon after seed harvest was an efficient and fast clean-up method in the field after harvest. However, due to problems with smoke emission, especially near traffic roads and populated areas, field burning is not recommended as a preferable straw management method.
Authors
Arne Fjellberg Per Holm Nygaard Odd Egil StabbetorpAbstract
No abstract has been registered
Abstract
Empirical evidence that the N dissipation from dairy production depends tightly on the segregation of animals from plant production is provided
Abstract
Empirical evidence that the N dissipation from dairy production depends tightly on the segregation of animals from plant production is provided
Authors
Solveig Haukeland Arild AndersenAbstract
Preliminary results from a Norwegian project performed 2005-2008 was presented. It includes identifying the geographical distribution and life cycle of the species in Norway, testing different methods for control in private gardens, and evaluating the nematode Phasmarhabditis hermaphrodita. Foreløpige resultater fra et norsk forskningsprosjekt 2005-2008 ble presentert. Det inkluderer utbredelse og livssyklus i Norge, utprøving av ulike bekjempingsmetoder i privathager, og evaluering av nematoden Phasmarhabditis hermaphrodita.
Authors
Christer Magnusson Karl Thunes Hans Nyeggen Hans Overgaard Trond Rafoss Solveig Haukeland May Bente Brurberg K. A. Strandenæs Bjørn Økland Bonsak HammeraasAbstract
The detection in 1999 of the pine wood nematode (PWN), Bursaphelenchus xylophilus, in Portugal triggered survey activities in many European countries. With the assumption that PWN would reach frequency 10 times lower than the native B. mucronatus and the requirement of a 95 % confidence limit suggested 2 995 samples to be required for a safe statement on the absence of PWN from the territory surveyed. Samples were taken from 10 circular areas with 50 km diameter erected from a point of import of risk materials. In the period 2000-2006 3 165 wood samples, 2 880 from Pinus sylvestris, 279 from Picea abies and 6 from unknown wood, were collected from 446 logging sites, in 84 municipalities and 13 counties. Of the total material 85 % of the samples came from cutting wastes, timber or lying trees. Wood showing signs of insect activity (incl. Monochamus) formed 73 % of the total material. Nematodes were recorded in 85 % of the samples. The order Rhabditida was most frequent, followed by the orders Aphelenchida, Tylenchida and Dorylaimida. Rhabditid nematodes were equally frequent in pine and spruce, while Aphelenchida (Aphelenchus, Aphelenchoides, Cryptaphelenchus, Seinura and Bursaphelenchus) and Tylenchida (Filenchus, Lelenchus, Ditylenchus, Deladenus and Nothotylenchus) tended to be more common in pinewood. Aphelenchoides was the most common genus. The genus Bursaphelenchus occurred in 1 % of the samples. B. mucronatus was detected in 0,3 % of the samples and most often in cutting waste of pine. The pine wood nematode (PWN), B. xylophilus, was not detected in this survey. The unexpected low natural occurrence of B. mucronatus indicates that the number of potential niches for PWN also is lower than expected, and hence it will be necessary to continue this surveillance program to reach 10 000 samples. The present zone sites in central and south-eastern Norway will be supplemented with 1-2 zone sites in southwestern region of the country. In the future these zone sites will function as permanent observation areas. Care will also be taken to collect all samples from detached wood with signs of Monochamus activity.
Authors
Sissel Hansen Marina Azzaroli Bleken Anne-Kristin Løes Espen Govasmark Anne Falk Øgaard Tor Arvid BrelandAbstract
No abstract has been registered