Publikasjoner
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.
2009
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Ricardo Holgado Stig Andersson Janet Rowe Ian Clark Christer MagnussonSammendrag
Norwegian cereal cyst nematode populations were studied by biochemical, molecular, morphological and bio test techniques. H. avenae occurred in the pathotypes, Ha11, Ha12, and H. avenae Våxtorp. H. filipjevi was recorded as pathotype West. H. avenae (Ha 11) and H. filipjevi West were the most common species. Thirty barley, 23 oat and 6 of summer wheat cultivars on the Norwegian market were tested for their resistance against H. avenae (Ha11), H. avenae Våxtorp and H. filipjevi West. Resistance against Ha11 was found in 5 barley, 3 oat and in 1 wheat cultivar. Resistance against H. avenae Våxtorp was not present in barley, but 4 oat and 1 wheat cultivar were resistant. For H. filipjevi West resistance was not detected in wheat, but in 6 barley and 13 oat cultivars. A management system based on careful nematode identification and knowledge on resistance of cultivars were set in operation in the county of Vestfold. As a result farmers have improved average yields by 1000 kg /ha. By implementing this program in full the county of Vestfold could make an annual gain of 800 000 €. In perspective of increasing damage from CCN world-wide the correct identification of species and the recognition of their genetic variability is instrumental for successful control.
Sammendrag
Yields are reported from four long-term (16 30 years) tillage trials, comparing results since 1998, under relatively wet conditions, with earlier experience. In trial 1, on clay loam, mean grain yield with spring harrowing only, has since 1998 been 87% of that obtained with autumn ploughing, whereas it was 94% for the whole period since 1991. The inclusion of autumn harrowing increased these figures to 94 and 98%, respectively. Over the last six years, spring ploughing gave 5% lower yield than did autumn ploughing. Relative yields of unploughed versus ploughed treatments were negatively correlated with summer rainfall. Grain protein was lowest with spring harrowing only. In trial 2, on clay loam, direct drilling has since 1998, as in previous years, given around 10% lower yield than has autumn ploughing. Autumn harrowing gave 4% lower yield in winter wheat and 6% higher yield in spring oats than did autumn ploughing, whilst yields of spring turnip rape were not significantly affected by tillage. In trial 3, also on clay loam, six alternative straw treatments were compared under four unploughed tillage regimes. Relative to straw removal, retaining large residue amounts depressed yields hardly at all with autumn and spring harrowing, but by 7% with spring harrowing only and by 13% with direct drilling. Overall, direct drilling gave 18% lower yields in this trial than did autumn and spring harrowing, whilst the yield reduction with spring harrowing only was 7%. In trial 4, on silt loam, both spring harrowing only and direct drilling have since 1998 given 6% lower yield than has autumn ploughing, whereas autumn and spring harrowing has given 6% higher yield. Under drier conditions during 1991 1997, autumn ploughing gave up to 11% lower yield than did unploughed treatments. Straw retention was beneficial in the absence of ploughing during that period, but has had little effect in more recent years.
Forfattere
Bent Braskerud Atle HaugeSammendrag
This report describes how small constructed wetlands (CWs) of approximately 0.1 % of the watershed area can contribute to cleaner waterways. The report summarises more than 10 years experience of investigation and construction of wetlands in Norway, where agricultural authorities finance the construction of wetlands. Investigations show that the average retention in the different wetlands was 45-75 % for soil particles, and 21-44 % for phosphorus (P). The retention of particles and P tends to increase with runoff due to erosion processes in the watershed. Higher constructed wetland (CW) effectiveness than expected is a combined effect of (i) clay particles entering wetlands as aggregates with higher sedimentation velocity than single particles, (ii) shallow depth which gives shorter particle settling distance, and (iii) vegetation cover preventing resuspension of sediment. The use of mineral filters can increase the P-retention performance under low runoff situations. Due to high hydraulic loads the redox potential in the outlet water indicated aerobic conditions. As a result the redox-sensitive P in the wetland sediment is conserved providing a sufficient amount of water flows through the CW. Small CWs have a minor effect on nitrogen (N) retention (3-15 %) due to the short detention time. Use of organic filters can increase the N-retention performance. However, these filters will decrease the P-retention, because the water becomes anoxic. Wetlands can reduce the pesticide content in water. The effect is correlated to the physical and chemical behaviour of the pesticide. As a result, retention could vary from 0 to 67 %. To summarise, the most important factor for pollution retention performance in small wetlands is properties of the watershed itself (such as type of agriculture, soil type, erosion rates, aggregate stability etc). Important design criteria are shallow (max. 0.5 m) and vegetated wetland filters, and location close to the source of pollution.
Forfattere
Svein Halvor Knutsen S. Dimitrijevic E. L. Molteberg Vegard Segtnan Lene Kaaber Trude WicklundSammendrag
Freeze-dried potato samples were obtained from the varieties Saturna and Peik that had been subjected to different agronomic conditions and storage. Powdered samples originating from the same growth year were mixed with oil and heated simultaneously in a stone oven in order to study the potential for acrylamide (AA) formation in a fixed time and temperature situation. For baked samples originating from unstored potato a linear relationship was found between asparagine (Asn) and reducing sugar (RS) content and AA formation. For these samples the AA content varied linearly with a* except from samples that originally were high or low in Asn. Upon storage the correlation between the quantity of the common precursors, Asn and RS, and AA were smaller. Results of the baking experiments suggest that the AA potential for stored potato cannot be predicted from RSs and Asn alone, and that other factors that might change during storage are of importance. Due to north European conditions the RSs might not always be the limiting substrate for AA formation. Additional information for the precursor content in 2004 and 2005 are included. No systematic effect on precursor contents related to chemical vine killing was observed. Precursor contents varied among and between varieties, different cultivation years and growth sites. (C) 2008 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.
Sammendrag
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Sammendrag
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Sammendrag
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Populærvitenskapelig – Gjødslingsnormer og sortsrespons for nitrogen til potet
Per Jarle Møllerhagen
Forfattere
Per Jarle MøllerhagenSammendrag
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Forfattere
Per SteinsholtSammendrag
Det er ikke registrert sammendrag