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
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Authors
Aruppillai Suthaparan Sissel Torre Arne Stensvand Maria Herrero Rolf Inge Pettersen David M. Gadoury Hans Ragnar GislerødAbstract
When rose plants bearing colonies of Podosphaera pannosa were placed in a wind tunnel, the number of conidia trapped was directly proportional to intensity of daylight-balanced (white) light from 5 to 150 mu mol m(-2) s(-1). Illumination of samples using blue (420 to 520 nm) light-emitting diodes (LEDs) increased the number of conidia trapped by a factor of approximately 2.7 over white light but germination of conidia under blue light was reduced by approximately 16.5% compared with conidia germination under white light. The number of conidia trapped under far-red (>685 nm) LEDs was approximately 4.7 times higher than in white light, and 13.3 times higher than under red (575 to 675 nm) LEDs, and germination was not induced compared with white light. When mildewed plants were exposed to cycles of 18 h of white light followed by 6 h of blue, red, far-red light, or darkness, light from the red LEDs reduced the number of conidia trapped by approximately 88% compared with darkness or far-red light. Interrupting the above dark period with 1 h of light from red LEDs also reduced the number of conidia trapped, while a 1-h period of light from far-red following the 1 h of light from red LEDs nullified the suppressive effect of red light. Our results indicate that brief exposure to red light during the dark interval may be as effective as continuous illumination in suppressing powdery mildew in greenhouse rose plant (Rosa x hybrida).
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J. Brian Hardaker Gudbrand LienAbstract
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May Sæthre Arnstein Staverløkk Eline HågvarAbstract
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This study focused on a suite of vascular plant species (six herbs and two grasses) common to traditionally managed, species-rich grasslands in Western Norway. We assessed the suitability of two species transfer methods (seed sowing and soil seed bank) for restoration of species-rich grassland on a newly established road verge. We compared the species\" frequencies one and three years after they were sown on a naked, newly created road verge with their frequencies in aboveground vegetation and soil seed banks of comparable, local grasslands. Species frequencies in the aboveground vegetation differed significantly from those in the seed banks. Moreover, the frequencies in the seed banks differed from those recorded one year after sowing, and the frequencies in the aboveground vegetation differed from those recorded three years after sowing. Avenula pubescens and Knautia arvensis, found in more than 25% of the aboveground grassland plots, did not germinate from any of the seed bank samples. Festuca rubra, Galium verum, Pimpinella saxifraga and Silene vulgaris were more frequent in the aboveground plots than in the seed bank samples. Pimpinella saxifraga, Galium verum and Lychnis viscaria emerged quite well both from sown seeds and from the seed bank. Avenula pubescens was frequent in the aboveground vegetation, but did not germinate from sown seeds. Six species established well from seeds, and most increased in frequency in the sown plots from the first to the third year. No species was found in the sown plots only, but three years after sowing, three species were more frequent in the sown plots than in the aboveground vegetation of donor grassland plots. Our fine-scale, point-to-point study demonstrates that different restoration methods produce widely differing species composition even when the donor material is identical. We propose that different substrates and a combination of establishment methods (sowing and hay transfer) are needed as supplements to seed banks to re-establish species-rich grassland.
Authors
Hanne Gro Wallin Tom Joar KristiansenAbstract
Our primary mission is to create an office in Juba with the necessary knowledge, computer equipment, GIS-software and the necessary satellite images. The office and its employees are going to be the independent land cover mapping authority in Southern Sudan. 4 persons from Norwegian Forest and Landscape institute had totally 11 stays in Juba in 2008. Our main task this year was to establish the office with equipment and expertise. The competence of the employees proved to vary a lot and in many cases to be inadequate. We started the transfer of knowledge on a very basic and simple level. The first year was celebrated by making a simple map showing the location of the known Forest Reserves in Southern Sudan at that time. The office had produced their first official map.
Authors
Hanne Gro Wallin Tom Joar KristiansenAbstract
The primary mission of the project is to create a Land Resource Survey and Information Centre in Juba with the necessary knowledge, computer equipment, GIS-software and the satellite images to map and monitor land resources. The office and its employees will be the independent land cover mapping authority in Southern Sudan. The Norwegian role is to support capacity building in the institution. The actual survey, mapping and monitoring activities should be carried out by the institution itself. The project was a continuation of work started in 2008. In 2009, more advanced training in GPS, digital mapping, remote sensing and production was carried out and a forest inventory was started. The office was upgraded with an installation of a battery backup system witch provide power enough to run the office for 3-5 hours in case of no electricity. A network of contacts with other relevant activities in South-Sudan was also established. The first land cover map produced by the office, covering the area between Yei and Juba, was produced based on interpretation in satellite images and verification in the field. The map “Forest reserves in Sothern Sudan” was upgraded to show the known forest reserves included as polygons with their actual shape and size.
Authors
Adam ParuchAbstract
No abstract has been registered