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
Authors
Nadeem Yaqoob Igor A. Yakovlev Paal Krokene Harald Kvaalen Halvor Solheim Carl Gunnar FossdalAbstract
We compared gene expression in Norway spruce secondary phloem (bark) and developing xylem (sapwood) in response to the necrotrophic pathogen Heterobasidion parviporum, wounding and methyl jasmonate (MeJ). The pathogen induced systemic and local up-regulation of PaPX3, PaPX2 and PaChi4 in both bark and sapwood that returned to constitutive levels as the plants recovered from the infection, whereas the local responses to MeJ were similar in both tissues but was longer lasting for PaPX3 and PaChi4. Genes involved in lignin biosynthesis (PaPAL1, PaPAL2, PaC4H3/5 and PaHCT1) were up-regulated locally in the bark in response to pathogen and wounding whereas MeJ induced a similar but stronger local response. The ethylene biosynthesis related transcripts PaACO and PaACS did not increase in response to MeJ treatment or the pathogen, however it increased both locally and systemically as a response to wounding in the sapwood. These results demonstrate that the local and systemic host responses to pathogen infection and wounding largely correspond and reveal striking similarities between the local response to a necrotroph, wounding and MeJ treatment in both bark and living wood.
Authors
Jahn Davik Gage Koehler Britta From Torfinn Torp Jens Rohloff Petter Eidem Robert Wilson Anita Sønsteby Stephen K, Randall Muath Alsheikh-YousefAbstract
The use of artificial freezing tests, identification of biomarkers linked to or directly involved in the low-temperature tolerance processes, could prove useful in applied strawberry breeding. This study was conducted to identify genotypes of diploid strawberry that differ in their tolerance to low-temperature stress and to investigate whether a set of candidate proteins and metabolites correlate with the level of tolerance. 17 Fragaria vesca, 2 F. nilgerrensis, 2 F. nubicola, and 1 F. pentaphylla genotypes were evaluated for low-temperature tolerance. Estimates of temperatures where 50 % of the plants survived (LT50) ranged from −4.7 to −12.0 °C between the genotypes. Among the F. vesca genotypes, the LT50 varied from −7.7 °C to −12.0 °C. Among the most tolerant were three F. vesca ssp. bracteata genotypes (FDP821, NCGR424, and NCGR502), while a F. vesca ssp. californica genotype (FDP817) was the least tolerant (LT50 −7.7 °C). Alcohol dehydrogenase (ADH), total dehydrin expression, and content of central metabolism constituents were assayed in select plants acclimated at 2 °C. The LT50 estimates and the expression of ADH and total dehydrins were highly correlated (r adh = −0.87, r dehyd = −0.82). Compounds related to the citric acid cycle were quantified in the leaves during acclimation. While several sugars and acids were significantly correlated to the LT50 estimates early in the acclimation period, only galactinol proved to be a good LT50 predictor after 28 days of acclimation (r galact = 0.79). It is concluded that ADH, dehydrins, and galactinol show great potential to serve as biomarkers for cold tolerance in diploid strawberry.
Abstract
No abstract has been registered
Authors
Tom Ericsson Karin Blombäck Agnar Kvalbein Angelika NeumannAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Peter Lindblad Pia Lindberg Paulo Oliveira Karin Stensjö Thorsten HeidornAbstract
No abstract has been registered
Authors
Eivind Vangdal P. Eccher Zerbibi M. Vaoli A. Rizzolo F. Lovati A. Toricelli L. SpinelliAbstract
During cold storage plums (Prunus domestica L.) are susceptible to developing internal disorders, such as jellying and internal browning. Time-resolved reflectance spectroscopy (TRS) is a promising method to detect internal disorders in fruit non-destructively. Experiments were performed with plums (‘Jubileum’) stored at 1 and 4°C for three weeks. Samples of 30 plums of uniform ripeness were measured during a 5 day shelf life period without storage or after 3 weeks of storage. In addition to TRS measurements (absorption coefficients and scattering coefficients at 670 and 780 nm) standard quality factors inlcuding colour, firmness, soluble solids content and titratable acidity were analyzed. The plums were cut in halves and the amount of internal disorders was evaluated from scale 0 (healthy) to 10 (all surface affected). The correlation between internal disorders and quality factors like firmness, soluble solids content and acidity indicated that more ripe plums were more susceptible to internal disorders. Colour parameters (L*, a* b*) showed significant and negative correlations with internal disorders. The absorption coefficients measured at 670 and 780 nm increased with the development of jellying and browning, which allowed distinguishing healthy fruit from those affected by internal disorders and the slightly browned fruit from those with medium and severe browning. Scattering coefficients were not influenced by chilling injury development
Authors
Ole Martin Bollandsås Timothy Gregoire Erik Næsset Bernt-Håvard ØyenAbstract
No abstract has been registered
Abstract
Increasing inter-continental trade of wood chips for biofuel represents a significant risk of introducing invasive pest species that can cause biome-scale impacts on forest ecosystems. Some potentially invasive species have the capacity to cause high tree mortality on the Eurasian continent and could cause significant impacts on biodiversity and ecosystem functions. Because eradication of established species is difficult, there is a need for scientific studies that can evaluate the reliability of current import control practices to ensure lowest possible risk of establishment of potentially harmful species. We used a stochastic simulation model and sensitivity analyses to evaluate the chance of detecting harmful pests in imported wood chips by sampling according to the current use of internationally accepted standards. As an example, we focused on the North American beetle Agrilus anxius (bronze birch borer) that can cause 100% mortality of European and Asian birch species in North America. We simulated the process from logging in North America to sampling the wood chips upon arrival in Europe. The probability of pest detection for current sampling protocols used by port inspectors was very low (<0.00005), while a 90% chance of detection may require sampling 27 million litres of wood chips per shipload.
Authors
Berit NordskogAbstract
No abstract has been registered