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
Authors
Katarzyna Dabrowska-Zielinska Piotr Golinski Marit Jørgensen Jørgen A.B. Mølmann Gregory Taff Stanislaw Twardy Monika Tomaszewska Barbara Golińska Maria Budzynska Martyna Gatkowska M KopaczAbstract
Grasslands are significant as a source of forage for animal production, but are also important in many ecological functions. To be able to analyse changes in environmental conditions of grasslands, monitoring of grassland areas using remote sensing is an important task. Studying changes in environmental condition over time and space in grasslands has been the subject of research at different scales. Such an example is the Polish-Norwegian Research Project FINEGRASS „Effect of climatic changes on grassland growth, its water conditions and biomass’. In situ measured soil-vegetation parameters and satellite observations have been combined and analysed to quantify the spatial and temporal variability of grassland conditions, as reflected in variations of vegetation surface temperature, soil moisture, and biomass. Results show a significant trend of increasing grassland surface temperature in Poland, based on AVHRR satellite data; a positive significant relationship between the (April-September) standardized precipitation evapotranspiration index (SPEI) and grass yields in Poland; northern Norway has shown trends towards warmer springs and autumns since 1991, and significant trends towards earlier snowmelt and green-up on test fields in northern Norway.
Authors
Tomasz Leszek Woznicki Anita Sønsteby Kjersti Aaby Berit Karoline Martinsen Ola M. Heide Anne-Berit Wold Siv Fagertun RembergAbstract
BACKGROUND Marked effects of the climatic environment on fruit chemical composition have often been demonstrated in field experiments. However, complex covariations of several climatic factors in the natural environment complicate the interpretation of such experiments and the identification of the causal factors. This can be better achieved in a phytotron where the various climatic factors can be varied systematically. Therefore, we grew four black currant cultivars of contrasting origin in a phytotron under controlled post-flowering temperature and photoperiod conditions and analysed the berries for their ascorbic acid, sugar and organic acid contents. RESULTS The analyses revealed significant effects of genotype on all investigated compounds. Particularly large cultivar differences were observed in the concentrations of l-ascorbic acid (AA) and sucrose. The concentrations of both AA and dehydroascorbic acid (DHAA), as well as the concentrations of all major sugars, decreased consistently with an increasing temperature over the temperature range 12–24 °C. Fructose and glucose were the predominant sugars with concentrations several fold higher than that for sucrose. AA was the main contributor to the total ascorbate pool in black currant berries. The AA/DHAA ratio varied from 5.6 to 10.3 among the studied cultivars. The concentration of citric acid, which was the predominant organic acid in black currant berries, increased with an increasing temperature, whereas the opposite trend was observed for malic and shikimic acid. Quninic acid was always present at relatively low concentrations. By contrast, photoperiod had no significant effect on berry content of any of the investigated compounds. CONCLUSION It is concluded that the post-flowering temperature has marked effects on the concentration of important chemical compounds responsible for taste and nutritional value of black currant berries, whereas photoperiod has no such effect in the studied cultivars. © 2016 Society of Chemical Industry
Abstract
The effect of fertility status and temperature conditions during floral induction on flowering, berry yield,and weight and drupelet numbers of individual berries were studied in ‘Glen Ample’ raspberries grownunder controlled conditions. Withdrawal of normal fertilization prior to and at various stages duringfloral induction did not affect yield and berry size, but marginally advanced flowering and fruit ripening.The successive stages of floral initiation and differentiation were studied and identified by scanning elec-tron microscopy of the uppermost lateral buds of plants grown for six weeks under naturally decreasingautumn photoperiods at temperatures of 9, 15 and 21◦C. Low temperature advanced floral initiation, andadvanced and enhanced flowering and berry yield in the following season. However, at variance fromearlier studies, the plants eventually initiated flower primordia even at 21◦C. Marginal low temperatureand short day conditions during the last days before the temperature treatments were started on 17September might possibly have reduced the subsequent induction requirements enough to explain thisunexpected result. Correlation analyses revealed an over-all positive correlation between fruit weightand drupelet numbers (r = 0.568, P = 0.01). In berries from the early harvests, the number of drupelets perberry increased with decreasing temperature, while the numbers converged to the same level regardlessof temperature in the later harvests. Based on the progress of the floral initiation process at the vari-ous temperatures, we interpret this to mean that only the early initiated flowers, that gave rise to theearly maturing berries, were differentiated during the actual period of controlled temperature exposure,whereas the remaining flowers were differentiated afterwards when all plants were exposed to identicallow temperature conditions. Increased femaleness under optimal floral induction conditions is in agree-ment with results in both monoecious and dioecious plants and circumstantial evidence suggest that,in the raspberry, this might be mediated by changes in gibberellin activity which acts as a male sexualhormone in plants and is known to inhibit growth cessation and floral initiation in raspberry.
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.
Authors
Tomasz Leszek Woznicki Kjersti Aaby Anita Sønsteby Ola M. Heide Anne-Berit Wold Siv Fagertun RembergAbstract
The effects of postflowering temperature and daylength on the concentration of individual phenolic compounds were studied in black currant (Ribes nigrum L.) berries under controlled phytotron conditions. The four cultivars studied varied greatly in their concentrations of individual phenolic compounds and temperature stability for accumulation. The concentrations of a wide range of identified phenolic compounds were strongly influenced by temperature over the 12–24 °C range, often with opposite temperature gradient patterns for compounds within the same subclass. Accumulation of anthocyanins and flavonols increased under natural long day conditions, which provided an increased daily light integral, while under identical light energy conditions, photoperiod had little or no effect on the concentration of phenolic compounds. Furthermore, with the exception of members of the hydroxycinnamic acid subclass, the concentration of most phenolic compounds was higher in berries ripened outdoors than in the phytotron, apparently due to screening of UV-B radiation by the glass cover.
Abstract
The growing season is longer than earlier and especially autumn temperatures have increased during the last 30 years (Hanssen‐Bauer et al 2015). A longer growing season increases the potential for forage production as an earlier spring, and warmer autumn implies that farmers can take more cuts with larger yields than earlier. Nevertheless, a warmer autumn can promote considerable regrowth after the last cut, and farmers report that they are uncertain if this regrowth should be harvested. The cost of harvesting forage is high, and feed quality of late harvested forage may be sub‐optimal. Changing precipitation patterns where there may be more episodes of heavy rains during autumn, late harvesting of grass swards can increase the risk of soil compaction and damage plant cover. This was the background to a study where we examine how different harvest time in autumn affects overwintering and yields the following year. We have established randomized block field experiments with 3 replicates in established leys dominated by timothy (Phleum pratense L.) at two sites in Norway in 2015; Kvithamar 63o29’N, 10o53’E, and Holt 69o38’N, 18o57’E. In the Kvithamar field, the main harvests were made June 30 and August 10. Thereafter, in one treatment, plots were left unharvested till next spring, while in other treatments plots were cut 4, 6, 8 or 10 weeks after the second main harvest. At Holt, the first harvest was made July 7, and the second harvest either August 11 or August 27. The regrowth after these treatments were either left uncut or harvested 4, 6 or 8 weeks after the last main cut in August 10, or 6 weeks after the cut in August 28. Dry matter yields were measured from all cuts. The results were analysed using ANOVA with MiniTab. No significant differences in yields were found between the different cutting treatments at either site, even though temperatures were between 2.2‐ 2.5oC higher than normal (1961‐1990) in September and between 1.1‐1.6 warmer than normal in October. Global radiation decreases rapidly from September onwards, and is a limiting factor for the growth potential of timothy‐dominated leys. In spring, we will measure winter survival and growth rate and yields in all treatments. The results from these measurements will be presented at the conference.
Abstract
The paper is a mini review on the climatic effects on berry production and berry quality in the Arctic north. Plants in the north are facing short growing seasons with low temperatures and long days with a unique light quality. The winter time is cold but with fluctuating temperatures, especially along the coast. Fluctuating winter temperatures and unstable snow cover is a challenge for the perennials that need to be dormant during winter time. Dormancy is induced in the autumn by a combination of day length and temperature. The wild berries domestic to the Nordic countries are adapted to these growth conditions while many of the commercially important berry species originate from more southern areas. Pre-breeding studies on interactions between genotype and environment are essential in order to develop climatically adapted berry cultivars for northern growth conditions.
Abstract
Grassland and the associated ruminant livestock production is the backbone of Norwegian agriculture, as ruminant products contribute nearly 50% of the gross income of the agricultural sector. About 2/3 of the agricultural area is used for temporary and permanent grassland, and a large proportion (40%) of the arable land is used for producing cereals that are included in concentrate mixtures fed to ruminants. The huge variation in climatic conditions, caused by the wide range in both latitude and altitude as well as in the distance to the coast, determines the land use and choice of species and varieties used in grassland. However, the dominating ley grassland species used in in almost all parts of the country are timothy (Phleum pratense L.), meadow fescue (Festuca pratensis Huds.) and red clover (Trifolium pratense L.). The use of perennial ryegrass (Lolium perenne L.) is increasing, particularly in the southwestern parts of the country. The grassland yields and forage feed quality have remained very much the same during the last decade, while the intensity in ruminant production, e.g. milk yield per cow, has increased considerably. Factors that have contributed to grassland yield stagnation are probably the increasing proportion of rented farmland by larger farm units, the increasing price ratio between livestock products and feed concentrates and the increasing cost of producing forage relative to the price of concentrates
Abstract
Grassland and the associated ruminant livestock production is the backbone of Norwegian agriculture, as ruminant products contribute nearly 50% of the gross income of the agricultural sector. About 2/3 of the agricultural area is used for temporary and permanent grassland, and a large proportion (40%) of the arable land is used for producing cereals that are included in concentrate mixtures fed to ruminants. The huge variation in climatic conditions, caused by the wide range in both latitude and altitude as well as in the distance to the coast, determines the land use and choice of species and varieties used in grassland. However, the dominating ley grassland species used in in almost all parts of the country are timothy (Phleum pratense L.), meadow fescue (Festuca pratensis Huds.) and red clover (Trifolium pratense L.). The use of perennial ryegrass (Lolium perenne L.) is increasing, particularly in the southwestern parts of the country. The grassland yields and forage feed quality have remained very much the same during the last decade, while the intensity in ruminant production, e.g. milk yield per cow, has increased considerably. Factors that have contributed to grassland yield stagnation are probably the increasing proportion of rented farmland by larger farm units, the increasing price ratio between livestock products and feed concentrates and the increasing cost of producing forage relative to the price of concentrates
Abstract
Effects of wilting rate and fermentation stimulators and inhibitors on protein characteristics of forages typ- ical for organic production were assessed using tradi- tional analytical methods and a gas production in vitro assay. The hypotheses were that the proportion of the crude protein (CP) fraction that was soluble would be lowest, and the protein feed value highest, under rapid wilting and restricted fermentation. The solubil- ity of the CP fraction varied according to treatments and between a first and a second cut, with moderate and high content of clover respectively. It was, how- ever, of minor importance for the protein value, both calculated as amino acids absorbed in the small intes- tine (AAT 20 ) and estimated as effective utilizable crude protein (uCP 04 ) by the in vitro assay. In ensiled her- bage, AAT 20 was highest in rapidly wilted and restrict- edly fermented silages made from a first cut dominated by highly digestible grasses. Silages from the second cut dominated by red clover were far lower in AAT 20 . The in vitro assay did not separate silages according to herbage composition or wilting rate, but ranked restrictedly fermented above extensively fer- mented with regard to protein supply. The assay might still have caught the characteristics that determine the true protein value in vivo.