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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.

2017

Abstract

The genus Pectobacterium, which belongs to the bacterial family Enterobacteriaceae, contains numerous species that cause soft rot diseases in a wide range of plants. The species Pectobacterium carotovorum is highly heterogeneous, indicating a need for re-evaluation and a better classification of the species. PacBio was used for sequencing of two soft-rot-causing bacterial strains (NIBIO1006T and NIBIO1392), initially identified as P. carotovorum strains by fatty acid analysis and sequencing of three housekeeping genes (dnaX, icdA and mdh). Their taxonomic relationship to other Pectobacterium species was determined and the distance from any described species within the genus Pectobacterium was less than 94% average nucleotide identity (ANI). Based on ANI, phylogenetic data and genome-to-genome distance, strains NIBIO1006T, NIBIO1392 and NCPPB3395 are suggested to represent a novel species of the genus Pectobacterium, for which the name Pectobacterium polaris sp. nov. is proposed. The type strain is NIBIO1006T (=DSM 105255T=NCPPB 4611T).

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Abstract

The plant hormone auxin is a vital component for plant reproduction as it regulates the development of both male and female reproductive organs, including ovules and gynoecia. Furthermore, auxin plays important roles in the development and growth of seeds and fruits. Auxin responses can be detected in ovules shortly after fertilization, and it has been suggested that this accumulation is a prerequisite for the developmental reprogramming of the ovules to seeds, and of the gynoecium to a fruit. However, the roles of auxin at the final stages of ovule development, and the sources of auxin leading to the observed responses in ovules after fertilization have remained elusive. Here we have characterized the auxin readout in Arabidopsis ovules, at the pre-anthesis, anthesis and in the immediate post-fertilization stages, using the R2D2 auxin sensor. In addition we have mapped the expression of auxin biosynthesis and conjugation genes, as well as that of auxin transporting proteins, during the same developmental stages. These analyses reveal specific spatiotemporal patterns of the different auxin homeostasis regulators. Auxin biosynthesis genes and auxin transport proteins define a prepatterning of vascular cell identity in the pre-anthesis funiculus. Furthermore, our data suggests that auxin efflux from the ovule is restricted in an anther-dependent manner, presumably to synchronize reproductive organ development and thereby optimizing the chances of successful fertilization. Finally, de novo auxin biosynthesis together with reduced auxin conjugation and transport result in an enhanced auxin readout throughout the sporophytic tissues of the ovules soon after fertilization. Together, our results suggest a sophisticated set of regulatory cascades that allow successful fertilization and the subsequent transition of the female reproductive structures into seeds and fruits.

To document

Abstract

There has long been a claim that winter injuries of grass are a significant economic burden for golf courses in the Nordic countries. To confirm this claim, in 2015 the Norwegian Institute of Bioeconomy Research and the Norwegian Golf Federation, with support of the Scandinavian Turfgrass and Environment Research Foundation, conducted a net-based survey about winter injury in the five Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden). This comprehensive survey showed that total costs of repair of winter-injured greens and fairways together with lost revenue on golf courses in the Nordic countries can be at least €14 million. In a year with significant winter injuries, the average cost to repair the turf was between €3000 and €12,000 on 88% of the courses. The revenue loss after a winter with considerable injuries was less than €6000 at 50% of the courses, and 25% of the courses reported a loss between €6000 and €12,000 for these years. The causes of winter injuries varied depending on geography and grass species used on the greens. Biotic factors played a major role in the southern part of Scandinavia, and ice and water injuries were most devastating north of 60°N. This paper summarizes some of the answers from the respondents, including information about the dominating grass species on Nordic golf greens.

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Abstract

Seed crops of white clover (Trifolium repens L.) are usually established with a cover crop. Provided sufficient light, white clover may compensate for low plant density by stoloniferous growth. Our objectives were (1) to compare spring barley or spring wheat used as cover crops for white clover and (2) to find the optimal seeding rate/row distance for white clover. Seven field trials were conducted in Southeast Norway from 2000 to 2003. Barley was seeded at 360 and 240 seeds m−2 and wheat at 525 and 350 seeds m−2. White clover was seeded perpendicularly to the cover crop at 400 seeds m−2/13 cm row distance or 200 seeds m−2/26 cm. Results showed that light penetration in spring and early summer was better in wheat than in barley. On average for seven trials, this resulted in 11% higher seed yield after establishment in wheat than in barley. The 33% reduction in cover crop seeding rate had no effect on white clover seed yield for any of the cover crops. Reducing the seeding rate/doubling the row distance of white clover had no effect on seed yield but resulted in slightly earlier maturation of the seed crop.

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Abstract

Global warming is predicted to adversely affect the reproduction of birds, especially in northern latitudes. A recent study in Finland inferred that declining populations of black grouse, Tetrao tetrix, could be attributed to advancement of the time of mating and chicks hatching too early—supporting the mismatch hypothesis. Here, we examine the breeding success of sympatric capercaillie, T. urogallus, and black grouse over a 38-year period in southeast Norway. Breeding season temperatures increased, being most pronounced in April. Although the onset of spring advanced nearly three weeks, the peak of mating advanced only 4–5 days. In contrast to the result of the Finnish study, breeding success increased markedly in both species (capercaillie: 62%, black grouse: 38%). Both brood frequency and brood size increased during the study period, but significantly so only for brood frequency in capercaillie. Whereas the frequency of capercaillie broods was positively affected by rising temperatures, especially during the pre-hatching period, this was not the case in black grouse. Brood size, on the other hand, increased with increasing post-hatching temperatures in both species. Contrary to the prediction that global warming will adversely affect reproduction in boreal forest grouse, our study shows that breeding success was enhanced in warmer springs.

Abstract

Konservering av mat har til alle tider vært en nødvendighet for å ta vare på råvarene og sikre mattilgangen. Både fisk, kjøtt, bær, korn, melk og egg var av naturlige grunner tilgjengelig i relativt store mengder i spesielle sesonger. Man utviklet derfor en rekke metoder for å ta vare på næringsstoffene i maten, og beskytte den mot nedbrytende elementer (mikroorganismer og enzymer). I denne artikkelen skal vi først og fremst se på den eldste konserveringsmetoden, tørking, med utgangspunkt i råstoffet torsk. Videre skal vi komme inn på en foredlingsprosess knyttet til tørrfisk, til spesialiteten lutefisk. Artikkelen kommer også inn på en mer moderne konserveringsmetode,salting, og dermed også klippfisk.

Abstract

Artikkelen tar for seg levetid for infiltrasjonsanlegg for avløpsvann og ser spesielt på binding av fosfor og gjentetting som kan begrense levetiden. Det refereres til norske og internasjonale undersøkelser. I Norge er det generelt gode erfaringer med infiltrasjon som rensemetode og regnes som en robust metode som tåler variasjoner i hydraulisk belastning og oppnår rensing på mange viktige parametere. Undersøkelser av eldre anlegg, etablert før 1985, viser imidlertid at anleggene ofte er plassert på dårlige egnede masser, har for lite areal eller mangelfull utforming i forhold til dagens krav. Infiltrasjonsanlegg i gode masser, og spesielt med nyere design, kan forventes å ha lang levetid (mer enn 20 ‐ 25 år), men lokale forhold kan begrense levetiden. Artikkelen har forslag til tema som bør undersøkes nærmere i forhold til å vurdere levetid på norske infiltrasjonsanlegg.