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.
2008
Forfattere
Hans Ragnar Norli Agnethe ChristiansenSammendrag
Cereals often give interfering peaks originating from fatty acids and their alkyl esters. The amount of interferences can be so high, that in addition to mask the target pesticides, the retention times increases and makes identification difficult. Standard QuEChERS cleanup with 25 mg/ml of PSA/ml of acetonitrile extract, or increasing the amount of PSA up to 300 mg/ml is not enough to remove the fatty acids. By adding calcium chloride to the extract, the polarity was changed in such a way that the polar pesticides were recovered in acceptable rates and fatty acids were not coextracted. By also include a freeze out step more unpolar fatty acid alkyl esters and plant sterols was removed.
Forfattere
Stein Rune Karlsen Anne Tolvanen Eero Kubin Jarmo Poikolainen Kjell Arild Høgda Bernt Johansen Fiona S. Danks Paul Eric Aspholm Frans Emil Wielgolaski Olga MakarovaSammendrag
Northern Fennoscandia is an ecologically heterogeneous region in the arctic/alpine-boreal transition area. Phenology data on birch from 13 stations and 16-day MODIS-NDVI composite satellite data with 250 m resolution for the period 2000 to 2006 were used to map the growing season. A new combined pixel-specific NDVI threshold and decision rule-based mapping method was developed to determine the onset and end of the growing season. A moderately high correlation was found between NDVI data and birch phenology data. The earliest onset of the growing season is found in the narrow strip of lowland between the mountains and the sea along the coast of northern Norway. The onset follows a clear gradient from lowland to mountain corresponding to the decreasing temperature gradient. In autumn, the yellowing of the vegetation shows a more heterogeneous pattern. The length of the growing season is between 100 and 130 days in 55% of the study area.
Forfattere
Marie-France Dignac C Rumpel Daniel Rasse M Mendez-Millan H Bahri S Derenne G Bardoux A MariottiSammendrag
How the chemical composition of plant biomolecules controls their dynamics in soils at the long-term scale remains largely unknown. Stabilisation mechanisms in soils might depend upon the chemical nature of organic matter. These mechanisms either involve soil mineral constituents or are related to chemical recalcitrance of specific molecules such as lignins. Physical and physico-chemical protection mechanisms may act differently on above- and belowground tissues of plants, leading to contrasting contributions of these tissues to soil organic matter (SOM). Cutins and suberins are specific for above and the belowground tissues of higher plants, respectively. Their molecular constituents can be used as biomarkers of the inputs of these plant tissues to soils. In this study, the molecular turnover of specifically plant-derived constituents in soils were estimated using compound specific isotopic tracer techniques applied to agricultural lands converted from C3 plant to C4 plant cropping. We assessed the specific residence times of lignins, cutins and suberins in soils, in order to compare the contributions of above- and belowground tissues to SOM. Lignin turnover in soil was faster than that of total organic carbon. Contrasting dynamics in soils were observed among lignin monomers as well as among cutin/suberin markers, which might be related to their chemical nature, their position into the polymeric structure and/or to the plant tissue in which they are present. This study, combining compound specific isotope measurements with a long term field trial helped understanding soil carbon turnover on a molecular level.
Forfattere
Gunnhild Wærsted Takle Ian Toth May Bente BrurbergSammendrag
During the last years, Norway and several other countries have seen an increase in potato blackleg disease caused by the Gram-negative bacterium Pectobacterium atrosepticum (formerly known as Erwinia carotovora ssp. atroseptica). P. atrosepticum has a narrow host range, limited almost exclusively to potato plants in temperate regions, where it also causes soft rot of potato tubers. The pathogen spreads from infected seed tubers to progeny tubers either through the plant or over short distances in the soil. However, little is known about how seed potatoes are initially contaminated with the bacterium and what onsets the infection. Our overall aim is to understand the underlying molecular mechanisms behind potato infection by P. atrosepticum and to find possible means of controlling blackleg disease, as well as providing more knowledge of the overall lifestyle of the bacterium. The sequencing and annotation of the genome of P. atrosepticum strain SCRI1043 (Bell et al., 2004. Proc.Natl.Acad.Sci. 101: 11105-10) as well as a genome-wide mutant library (Holeva et al., 2004. Mol. Plant. Microbe. Interact. 17:943-50) provide valuable tools in examining the molecular aspects of both pathogenesis and environment related factors. Quorum-sensing seems to play an essential role in the pathogenesis of P. athrosepticum, and we are currently studying some of the many genes affected by this regulatory control as well as other putative virulence genes.
Forfattere
Anne-Cathrine Scheen Charlotte Lindqvist Carl Gunnar Fossdal Victor A. AlbertSammendrag
The five mint genera Brazoria, Macbridea, Physostegia, Synandra and Warnockia (Lamioideae: Lamiaceae) are all North American endemics. Together with the monotypic European genus Melittis and the Asian genus Chelonopsis, these taxa have been classified as subtribe Melittidinae. Previous morphological studies have failed to uncover synapomorphic characters for this group.We sequenced the plastid trnL-trnF region and trnS-trnG spacer and the nuclear ribosomal 5S non-transcribed spacer (5S-NTS) to assess phylogenetic relationships within Melittidinae. Standard parsimony and direct optimization (POY) analyses show Melittis, the type genus of the subtribe, as sister to Stachys. Thus, the monophyly of subtribe Melittidinae is not supported either by molecular or morphological data...
Forfattere
Carl Gunnar Fossdal Ari M. Hietala Igor A. Yakovlev Halvor SolheimSammendrag
The root-rot causing fungus Heterobasidion annosum sensu lato is the most devastating pathogen of conifers in Europe. This pathogen enters Norway spruce through the roots and can colonize the tree from within, growing as a saprophyte when established within the dead heartwood and acting as a necrotroph when in contact with living host tissue. Despite the high incidence of damage, trees have defences against this pathogen in the bark and living wood. Furthermore, spruce has a defense against internal attack by forming a reaction zone, in this case the host defense is directed inwardly by the still living sapwood toward the central colonized heartwood. We have studied the host responses to infection in Norway spruce clones at the transcriptional level and found that the speed of recognition and that spatial defense signalling appears to be the hallmarks of trees with high degree of resistance...
Forfattere
Marianne Bechmann Johannes Deelstra Per Stålnacke Hans Olav Eggestad Lillian Øygarden Annelene PengerudSammendrag
Det er ikke registrert sammendrag
Sammendrag
This paper discusses the monitoring network for diffuse pollution from agriculture in Estonia in the context of implementation of the EU Water Framework Directive (WFD) and the Nitrate Directive (ND). Seven surface water monitoring stations in agricultural catchments represent two out of three river basin districts designated in Estonia according to the WFD criteria. The national monitoring programme of ground water quality involves 516 stations of which about half were monitored in 2005. The monitoring sites cover all main ground water bodies in Estonia but are largely concentrated in the Nitrate Vulnerable Zone (NVZ). Analyses did not reveal any significant trends in total nitrogen (TN) and total phosphorus (TP) concentrations in studied rivers during the last 15 years except in one site. The ground water quality stabilised after decrease of nitrate concentrations in the early 1990s, especially in the south part of the NVZ, but even in 2005 the nitrate concentration exceeded 50 mg l1 in 42 out of 145 ground water samples in this region. The existing surface water quality monitoring network provides only restricted information to select between different management options when implementing action programmes for the NVZ and the river basin management plans (RBMP) under the WFD.
Forfattere
Jerry Cross Catherine Baroffio Alberto Grassi David Hall Barbara Labanowska Slobodan Milenkovic Thilda Nilsson Margarita Shternshis Christer Torneus Nina Trandem Gabor VetekSammendrag
The sex pheromone of the raspberry cane midge has been identified and synthesised by East Malling Research and Natural Resourced Institute and has proved to be highly attractive and useful for pest monitoring. EMR coordinated a collaborative ring test of standard raspberry cane midge sex pheromone traps in 2006. The aims were to investigate the seasonal temporal pattern of the midge flight in different raspberry production regions of Europe and the relationship between the magnitude of catches and the numbers of eggs and larvae which developed subsequently in artificial splits in the primocane of untreated raspberry plantations. The standard raspberry cane midge sex pheromone trap used for the ring test consisted of a white delta trap containing a 20 x 20 cm sticky base and a rubber septum lure impregnated with 10 μg of the raspberry cane midge sex pheromone racemate. Pairs of traps, separated by >20 m, were deployed in the centre of raspberry plantations at a height of 0.5 m in Italy, Hungary, Norway, Poland, Russia, Serbia, Sweden, Switzerland, and the UK. The traps proved effective and easy to use for monitoring the flight of adult male raspberry cane midge. There were very large variations (> 30 fold) between plantations in total numbers of midges caught over the season, indicating plantations which are at comparatively low and high risk from the pest. Three generations of adult flight were apparent in Norway, Russia and Sweden and four generations in the central European countries with possibly 5 generations in Italy, though later generations were often difficult to distinguish. In the northern countries, the 1st generation first and peak flight occurred on Julian days 150 and 165, respectively, whereas in Italy the 1st generation first and peak flight occurred approximately on Julian days 110 and 130 respectively. The 1st generation flights occurred much earlier in polytunnel protected crops than in open field crops. Data obtained on the occurrence of larvae were variable in quality but a linear relationship between the peak numbers of males captured in the pheromone traps per week for a given generation (M) and the peak numbers of eggs and larvae per cm in splits in the primocanes for that generation subsequently (L) was apparent (L = 0.025 M; R2=0.61). A nominal threshold of 30 midges per trap per week had been proposed but the linear relationship derived indicates that this threshold, which would result in ~ 0.75 eggs + larvae/cm, is too high. In reality, the degree of larval infestation that occurs and the resultant severity of crop damage will depend on the numbers of natural splits in the crop. The ring test is being continued in several countries in 2007.
Forfattere
V. Rahjoo J. Zad M. Javan-Nikkhah A. Mirzadi Gohari S.M. Okhovvat M.R. Bihamta Jafar Razzaghian Sonja KlemsdalSammendrag
Det er ikke registrert sammendrag