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.
2012
Abstract
The flight responses of 750 female Calliphora vicina Robineau-Desvoidy, 1830 (Diptera: Calliphoridae) are investigated in a wind tunnel bioassay. The attraction of C. vicina towards dead mice and seven different synthetic lures made from dimethyl trisulphide, mercaptoethanol and O-cresol is compared. Responses towards natural odours and the three-component synthetic kairomones depend on the flies' ovarian egg developmental status. The natural and three-component lures also induce similar age-dependent responses, although the dead mice lure yields a significantly higher attraction. Oriented flight increases with the number of chemicals in the synthetic kairomone; one-, two- and three-compound lures induce 13–25%, 32–43% and 62% attraction, respectively. Responses to one-component lures are not significantly influenced by egg developmental status, whereas blends of two or three components are. Attraction levels increase in a stepwise manner both across egg developmental categories and with the number of compounds. The results suggest that the attractiveness of synthetic kairomones is influenced not only by the blowflies' physiological state, but also by the complexity of the lure.
Authors
Gage Koehler Jens Rohloff Robert Wilson Per Winge Anita Sønsteby Muath Alsheikh Stephen K, RandallAbstract
There is limited research about variations between cultivars for freezing tolerance in fruit crops and indeed much less is known about the distinctive in ground structure of the crown that herbaceous perennials depend on for regeneration in spring. Because strawberry is a representative species for the Rosaceae crops knowledge gained is expected to be transferrable to benefit improvement of many of these related crops. To gain insight into the molecular basis that may contribute to overwintering hardiness, a comparative proteomic analysis was carried out for four Fragaria x ananassa (octoploid strawberry) cultivars that differ in freezing tolerance. Protein expression was investigated in the overwintering relevant crown structure of strawberry from plants exposed to 0, 2, and 42 day cold treatments and were examined by two-dimensional gel electrophoresis (2D). Some proteins, such as molecular chaperones, antioxidants / detoxifying enzymes, metabolic enzymes, and pathogenesis related proteins were revealed to be at significantly higher levels before cold exposure in the most freezing tolerant cultivars, (‘Jonsok’ and ‘Senga Sengana’) compared to the least tolerant cultivars (‘Frida’ and ‘Elsanta’). Freezing tolerance was evaluated for the cultivars before and after cold exposure, with findings that support that the most freezing tolerant cultivars are poised for rapid adaptation to cold exposure, suggesting potential differences in capacity or rate for cold acclimation. Thus, the molecular basis for enhanced overwintering survival may be related to the elevated basal level of a number of proteins, many of which are known to confer stress tolerances. These findings are presented and overlaid with a LFQP shotgun analysis and microarray analysis. This study presents the largest quantitative proteomic data-set for strawberry crown tissue during cold exposure to date. Through the comparison of these cultivars that differ in freezing tolerance, proteins that may contribute to cold tolerance but lack significant cold induction were revealed.
Authors
Jack D'Arcy Evgenia Dunaevskaya J.W. Treasurer Oddvar Ottesen Julie Maguire Nonna Zhuravleva Åsbjørn Karlsen Celine Rebours Richard FitzgeraldAbstract
No abstract has been registered
Abstract
Harvest activity directly impacts timber supply, forest conditions, and carbon stock. Forecasts of the harvest activity have traditionally relied on the assumption that harvest is carried out according to forest management guidelines or to maximize forest value. However, these rules are, in practice, seldom applied systematically, which may result in large discrepancies between predicted and actual harvest in short-term forecasts. We present empirical harvest models that predict final felling and thinning based on forest attributes such as site index, stand age, volume, slope, and distance to road. The logistic regression models were developed and fit to Norwegian national forest inventory data and predict harvest with high discriminating power. The models were consistent with expected landowners behavior, that is, areas with high timber value and low harvest cost were more likely to be harvested. We illustrate how the harvest models can be used, in combination with a growth model, to develop a national business-as-usual scenario for forest carbon. The business-as-usual scenario shows a slight increase in national harvest levels and a decrease in carbon sequestration in living trees over the next decade.
Authors
J.W. Treasurer Richard Fitzgerald Julie Maguire Celine Rebours Åsbjørn KarlsenEditors
Oddvar OttesenAbstract
No abstract has been registered
Abstract
Working paper 2012-1 presents the outcome of the project “Miljø- og klimaanalyse for norsk landbruk og matsektor” (Analysis of Environmental and Climate-related aspects of Norwegian agri-food sector). The project has been led by NILF in cooperation with MiSA and John Hille. The objective has been to develop methodological guidelines for comprehensive assessments of measures aimed at relieving environmental and climatic stresses from Norwegian food production and consumption.
Abstract
Bilberry (Vaccinium myrtillus L.), also called European blueberry, is native to Norway and strongly preferred by the Norwegian food industry due to its genuine flavour and high content of phytochemicals. However, Norwegian natural resources are underexploited, and only few investigation have focused on quality aspects of bilberries from wild populations with regard to potential cultivation and industrial utilization. Important goals of the 4-years study were to investigate (a) Berry quality parameters, (b) Fertilization effects, and (c) Geographic and seasonal variation in trial locations at regions in Southern, Mid and Northern Norway. Berry quality assessment included parameters such as total anthocyanins (ACY) and phenols (TPH), antioxidant capacity (AOX), pH, titratable acidity (TAC) and soluble solids (SS). Based on multivariate statistics (PCA), regional segregation patterns could be observed which were strongly overlapped by year-to-year variation. Within-seasonal variation of parameters were recorded for berries harvested at different time points throughout the season (Southern location/ Hedmark), but between-seasonal effects were generally stronger. Similar year-to-year effects were also found in bilberries from Northern Norway (Bardu), but not in berries harvested from the field in Mid Norway/Langvatnet. The field in Northern Norway was treated with organic fertilizer (compost and wood chippings), while the field in Mid Norway was fertilized with mineral fertilizer combinations (N+P). Application of organic fertilizer did not have any clear effect on berry quality, while mineral fertilizer resulted in clear segregation patterns of berry samples after three years of treatment, thus minimizing year-to year variation. Mean values of quality parameters ACY, TPH and AOX, measured at the different locations (all years and treatments) varied between 330-427 mg/100 g f.w., 531-640 mg/100 g f.w., and 5-8 mmol/100 g f.w., respectively, thus underscoring the phytochemical value of bilberries from Norwegian populations.
Authors
Joahnne E. Schjøth Leif SundheimAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Stein Michael Tomter Patrizia Gasparini Thomas Gschwantner Petra Hennig Gintaras Kulbokas Andrius Kuliesis Heino Polley Nicolas Robert Jacques Rondeux Giovanni Tabacchi Erkki TomppoAbstract
Estimates of growing stock in European countries vary mainly by using different thresholds for dbh of sample trees, as well as by the inclusion or exclusion of stump and stem top volume. European national forest inventories use dbh thresholds ranging from 0 to 12 cm in estimating the volume of growing stock. COST Action E43 has agreed to a reference definition for growing stock with a dbh threshold of 0 cm. With use of national volume distributions by dbh classes, models for estimating the proportions of growing stock between the national threshold and the 0-cm threshold were constructed. Models for characterizing growing stock distributions were tested, and their predictive abilities were investigated. Similar comparisons were made with respect to the volume of stumps and stem tops. Examples of estimation methods and the resulting percentages of these tree elements of total growing stock are presented.