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.
2010
Forfattere
May Bente Brurberg Xiaoren Chen Jahn Davik Håvard Eikemo Inger Martinussen Monica Skogen Yang Hu Abdelhameed Elameen Sonja KlemsdalSammendrag
Phytophthora cactorum causes crown rot in strawberry (Fragaria x ananassa Dutch.), which is characterized by wilting and eventually collapse of the plant. An efficient control measure is the use of resistant cultivars, however most commercial cultivars are susceptible to the disease. The aim of our work is to generate basic knowledge about P. cactorum resistance as well as to develop genetic markers that can be used as tools for development of resistant cultivars. The genetic complexity of the octoploid cultivated strawberry, has led to development of the diploid wild strawberry (F. vesca) as a model system for Fragaria. We have identified suitable parents after screening accessions of diploid Fragaria sp. for resistance [1], and generated a mapping population which we are currently characterizing. In order to study the plant-pathogen interaction in detail we have identified and characterized resistance genes from diploid strawberry and effector genes from P. cactorum using different transcriptional analysis techniques; nucleotide-binding site (NBS)-profiling for resistance genes, and suppression subtractive hybridization (SSH) as well as a designed effector-specific differential display (ESDD) for genes involved in pathogenicity. This work is supported by The Research Council of Norway. [1] Eikemo H, Brurberg MB, Davik J (2010). Resistance to Phytophthora cactorum in diploid Fragaria species. HortScience. 45:193-197.
Forfattere
May Bente BrurbergSammendrag
Phytophthora cactorum causes crown rot in strawberry (Fragaria x ananassa Dutch.), which is characterized by wilting and eventually collapse of the plant. An efficient control measure is the use of resistant cultivars, however most commercial cultivars are susceptible to the disease. The aim of our work is to generate basic knowledge about P. cactorum resistance as well as to develop genetic markers that can be used as tools for development of resistant cultivars. The genetic complexity of the octoploid cultivated strawberry, has led to development of the diploid wild strawberry (F. vesca) as a model system for Fragaria. We have identified suitable parents after screening accessions of diploid Fragaria sp. for resistance [1], and generated a mapping population which we are currently characterizing. In order to study the plant-pathogen interaction in detail we have identified and characterized resistance genes from diploid strawberry and effector genes from P. cactorum using different transcriptional analysis techniques; nucleotide-binding site (NBS)-profiling for resistance genes, and suppression subtractive hybridization (SSH) as well as a designed effector-specific differential display (ESDD) for genes involved in pathogenicity. This work is supported by The Research Council of Norway. [1] Eikemo H, Brurberg MB, Davik J (2010). Resistance to Phytophthora cactorum in diploid Fragaria species. HortScience. 45:193-197.
Forfattere
May Bente Brurberg Xiaoren Chen May Bente Brurberg Sonja KlemsdalSammendrag
The oomycete Phytophthora cactorum causes crown rot in strawberry, resulting in big economic losses. To unravel the molecular mechanisms that are involved in the pathogenicity of P. cactorum on strawberry, two strategies were followed, SSH cDNA library and effector specific differential display (ESDD). Two cDNA libraries were made, enriched for P.cactorum genes upregulated during infection of strawberry or in in vitro germinating cysts (a developmental stage essential for infection). Recent characterization of oomycete AVR/effector genes revealed that they encode proteins with conserved RxLR-dEER motifs required for translocating these effectors into host cells. The presence of such a conserved "tag" has provided a tool for discovering the otherwise structurally diverse effector genes. To select RxLR effector genes from P. cactorum, ESDD was performed on seven cDNA populations including four developmental stages (mycelium, sporangia, zoospores,germinating cysts) as well as three time points during infection (3, 5, 7 days postinoculation),using RxLR and EER primers. Using these strategies more than 230 gene fragments were isolated. Nearly 30 % of the genes could not be assigned a coding function, using sequence similarity-based function prediction, because either no similar sequences were detected or similarities were found only to putative proteins with unknown function (mostly oomycete). However, several genes potentially relevant for pathogenicity, including several putative RxLR effector and elicitor genes were discovered. The expression of 27 of these genes was studied in detail using real-time RT- PCR, and their upregulated expression during infection relative to dispersal propagules (sporangia) were confirmed for all but one.
Sammendrag
Sturite et al. (2007) investigated growth and death of the major parts of white clover (Trifolium repens L. cv. "Snowy") plants in pure stand and in mixture with meadow fescue (Festuca pratensis L. cv. "Fure") in a combined plot and root window experiment in Norway (60°42"N, 10º51"E). Leaves, stolons and roots were tagged and their lifespan was monitored in harvested and non-harvested stands during two experimental years. The longevity of leaves and petioles ranged from 21 to 86 d (mean = 59 d). About 60% of the leaves produced during the growing season turned over before the autumn. Of the remaining leaves, 70-80 % were dead or had disappeared by the subsequent spring. The lifespan of sections of the main stolons ranged from 111 to over 677 d (mean = 411 d). In particular, stolon sections close to the parent fragment of undisturbed plants were long lived, while sections towards the terminal bud overwintered more poorly and had a much shorter lifespan. The longevity of roots was from 27 to 621 d (mean = 290 d) and was higher for roots appearing in spring and autumn than in summer. Harvesting significantly reduced the longevity of stolons and caused an increased fragmentation of the white clover plant but did not decrease leaf/petiole or root lifespan.
Forfattere
Annbjørg Øverli KristoffersenSammendrag
Det er ikke registrert sammendrag
Forfattere
Annbjørg Øverli KristoffersenSammendrag
Det er ikke registrert sammendrag
Forfattere
Ole Martin Eklo Randi Bolli Jens Kværner Tore Sveistrup Eivind Solbakken Frauke HofmeisterSammendrag
In the project "Groundwater and Dependent Ecosystems: New Scientific and Technological Basis for Assessing Climate Change and Land-use Impacts on Groundwater (GENESIS)" coordinated by Bioforsk, the objective is to integrate new methods, concepts and tools for the revision of the Ground Water Directive and better management of groundwater resources. By case studies in different climatic regions various land use pressures are studied.To identify threatens to groundwater pollution MACRO_GV has been used simulating the movement of pesticides used in potatoes and cereals. The simulation set-up and output from the tool was similar to the FOCUS groundwater scenarios. The different soil-types of the area have large differences in risks of leaching to groundwater for the different pesticides. Risk reduction is possible with userfriendlyknowledge about soil and hot spots.
Forfattere
Svein SkøienSammendrag
Det er ikke registrert sammendrag
Konferansebidrag og faglig presentasjon – Jordbruk og miljø. Tiltak mot vannforurensing
Svein Skøien
Forfattere
Svein SkøienSammendrag
Fagsamling om kommunens rolle som forurensingsmyndighet. Fylkesmannen i Nord-Trøndelag. Kvithamar 15. september
Sammendrag
Advantages:•Better animal welfare •Better utilization of local wood resources, preserve open landscape •Easy to combine with bio energy production •Flexible buildings, economy? •Local added value Challenges:•Optimise composting process •Manurial value •Competence •Effective production of woodchips