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.
2016
Abstract
Berry yield and chemical composition of four commercial black currant cultivars were recorded in a field experiment in Norway over an 8-year period and related by linear regression analysis to temperature and precipitation conditions prevailing during the May-July preharvest period. Highly significant differences between cultivars and among years were found for all measured parameters. Fruit dry matter, soluble solids and pH were positively correlated with temperature and negatively correlated with precipitation during May-July, while yield, berry weight, and the concentration of total phenols and ascorbic acid showed the opposite relationship, being highly negatively correlated with temperature and positively correlated with precipitation. Similar black currant experiments elsewhere in Europe have often given deviating results, varying from opposite to no effects of the same weather variables, suggesting that fruit composition is influenced by several interacting genetic and environmental parameters. We conclude that differences in local weather and soil conditions and the use of different cultivars complicate direct comparison of such field experiments. Nevertheless, the observed strong and opposite correlations with precipitation and temperature suggest an inherently low drought tolerance of black currant plants.
Abstract
Effects of three different pasture allocation techniques on milk yield and quality with mid-lactation dairy cows
Abstract
We assessed milk production with 24 mid-lactation Norwegian Red dairy cows on a spring pasture dominated by timothy (Phleum pratense) for a period of 21 days using three pasture allocation techniques (n=8). Cows received weekly allowances at once (7 day-set-paddocking; 7SP), grazed 1/7 of 7SP allowance each day (daily-strip-grazing; 1SG), or grazed like 1SG but also had access to the previously grazed part of the paddock (daily-forward-grazing; 1FG). We hypothesized that 7SP would deteriorate sward quality and quantity over the grazing days whilst the other two treatments would provide balanced pasture quality and intake. These changes were expected to result in differences in milk yield and its components. However, changes in sward chemical composition (e.g. neutral netergent fiber, crude protein) over the grazing days in each week were not different among treatments (treatment × grazing day; P>0.05). Furthermore, no effect of treatments on milk yield and its components was observed. Nonetheless, the effects of grazing days over a week on milk yield and components were different among treatments (treatment × grazing day; P<0.05). These treatment by grazing day interaction effects, in the absence main effect of treatment, could be due to fluctuations in daily DMI among treatments over the grazing days in each week.
Abstract
We assessed milk production with 24 mid-lactation Norwegian Red dairy cows on a spring pasture dominated by timothy (Phleum pratense) for a period of 21 days using three pasture allocation techniques (n=8). Cows received weekly allowances at once (7 day-set-paddocking; 7SP), grazed 1/7 of 7SP allowance each day (daily-strip-grazing; 1SG), or grazed like 1SG but also had access to the previously grazed part of the paddock (daily-forward-grazing; 1FG). We hypothesized that 7SP would deteriorate sward quality and quantity over the grazing days whilst the other two treatments would provide balanced pasture quality and intake. These changes were expected to result in differences in milk yield and its components. However, changes in sward chemical composition (e.g. neutral netergent fiber, crude protein) over the grazing days in each week were not different among treatments (treatment × grazing day; P>0.05). Furthermore, no effect of treatments on milk yield and its components was observed. Nonetheless, the effects of grazing days over a week on milk yield and components were different among treatments (treatment × grazing day; P<0.05). These treatment by grazing day interaction effects, in the absence main effect of treatment, could be due to fluctuations in daily DMI among treatments over the grazing days in each week.
Abstract
No abstract has been registered
Abstract
A future wetter climate in Northern Europe may increase soil compaction from traffic of heavy machinery. This study investigated the impact of tractor traffic on grassland yield, soil physical properties and penetration resistance in three experimental field trials in Norway; on medium sand at Tjøtta, Nordland, on silty medium sand at Fureneset, Sogn og Fjordane and on silt at Løken, Oppland. The experiments were conducted in a split-plot design with three levels of two wheel-by-wheel passes with tractor traffic after each cut: no traffic, light tractor or heavy tractor on large plots, and three different seed mixtures on small plots. The yield reduction by tractor traffic was 26% at Løken, 4% at Fureneset and 1% at Tjøtta. There was a positive correlation between soil moisture content and yield reduction by traffic. Tractor traffic reduced pore volume and air capacity and increased bulk density, compaction degree and penetration resistance with the largest effect at Løken and the smallest at Tjøtta. There were no statistically significant differences in yield or soil physical properties between light and heavy tractor. The study shows that soil texture and soil moisture content are major factors explaining traffic effects on soil physical properties and grassland yield.
Abstract
This study examined the P fertilization effects of 11 sewage sludges obtained from sewage treated with Al and/or Fe salts to remove P by a pot experiment with ryegrass (Lolium multiflorum) and a nutrient-deficient sand−peat mixture. Also it investigated whether fertilization effects could be predicted by chemical sludge characteristics and/or by P extraction. The mineral fertilizer equivalent (MFE) value varied significantly but was low for all sludges. MFE was best predicted by a negative correlation with ox-Al and ox-Fe in sludge, or by a positive correlation with P extracted with 2% citric acid. Ox-Al had a greater negative impact on MFE than ox-Fe, indicating that Fe salts are preferable as a coagulant when aiming to increase the plant availability of P in sludge. The results also indicate that sludge liming after chemical wastewater treatment with Al and/or Fe salts increases the P fertilization effect.
Abstract
No abstract has been registered
Authors
Mehreteab TesfaiAbstract
This report gives a comprehensive review of current knowledge on nitrous oxide (N2O) emissions from mineral soils with special reference to the Norwegian agriculture and some research results from other countries. The report starts by highlighting the importance of N2O followed by descriptions of the pathways to N2O production and factors affecting N2O emissions from agricultural soils and measurement techniques and modelling N2O emissions. This is followed by reviewing and discussing research results on the effects of soil management practices including fertilizer application, soil compaction, soil tillage, effects of soil moisture and drainage conditions, effects of soil pH, freezing-thawing effects and effects of soil drying and rewetting on N2O emissions. Furthermore, some relevant mitigation measures to reduce N2O emissions are presented. The report concludes by suggesting future research needs to measure and mitigate soil N2O emissions.
Authors
Marc Ghesquière Joost Baert Susanne Barth Vladimir Cernoch Dermot Grogan Mike Humphreys Phil Murray Liv Østrem Dejan Sokolović E Paszkowski Z. ZwierzykowskiAbstract
Ryegrass x fescue interspecific hybridization (so-called Festulolium) has great potential for forage diversification because of its many amphiploid and introgression-bred forms. Festulolium breeding efforts aim to improve adaptation to mainly winter cold and summer drought through higher abiotic stress tolerance. This goal must be met with a minimum of compromise regarding productivity in the first years of full exploitation. To compare field performances, a 21-entry trial of Festulolium and controls of pure species has been ongoing since 2012 in eight European countries. The yield data collected in 2012 and 2013 in nine locations showed that the Festulolium cultivars performed on average quite well compared to pure species controls. In amphiploids, the annual yield appeared to be mainly driven by the Lolium sp. parent combined with F. pratensis (Fp); the Lm x Fp amphiploids performed thus far better on average than the Lp x Fp equivalents. The only amphiploid from F. glaucescens included in the study had an intermediate response over locations, which was closer to tall fescue than to F. pratensis. Interestingly, a broad variability for yield among the Lm x Fp cultivars appeared to be associated with climate interactions when cold, wet locations were contrasted with more temperate locations with early spring growth.