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.
2002
Forfattere
Bernt-Håvard Øyen Kjell AndreassenSammendrag
Det er ikke registrert sammendrag
Forfattere
Bernt-Håvard Øyen Kjell AndreassenSammendrag
Det er ikke registrert sammendrag
Forfattere
Mats Høglind Helge BonesmoSammendrag
The nutritive value of timothy, the most widely grown sown grass species for silage and hay production in Scandinavia, varies considerably among years due to varying environmental conditions. This makes it difficult to predict the economically optimum harvest time, which represents a compromise between herbage quantity and quality: the DM yield increases with advanced stage of sward development whereas the nutritive value decreases. The aim of this work was to investigate the possibilities to develop a mechanistic model to predict rates of change in digestibility and fibre content in Norwegian timothy. Here, we present the basic features of the model and make a first evaluation against field data.
Sammendrag
Modellutprøving ble foretatt på grunnlag av data fra 10 norske gjødslingsfeltforsøk med sommerkål, vinterkål og kepaløk dyrket på ulike jordarter i distrikt med ulik nedbør. Tilvekstkurver og N-opptaksmønsteret gjennom sesongen ble bestemt i alle forsøkene. På dette grunnlaget ble modellens funksjoner for vekst og N-gjenvinning forbedret.
Forfattere
G. van TolSammendrag
Det er ikke registrert sammendrag
Sammendrag
The flow and transport of a non-reactive tracer and melt water was monitored in a heterogeneous coarse sandy unsaturated zone in southeastern Norway, during the snowmelt of 2001. Electrical resistivity tomography (ERT) as well as conventional suction cup techniques was employed. A frozen solution of NaBr in water was supplied as a line source on the ground surface above two parallel vertical profiles monitored by the two measurement systems prior to the onset of snowmelt. The two monitored vertical profiles were separated by approximately 1 m. The results were analysed by visual comparison of images and by the use of spatial moments analysis. The two measurement approaches showed that the system was affected by the presence of preferential flow paths during the early stages of the snowmelt, perhaps due to ice near the surface, but the major part of the plume moves uniformly later in the snow-melting period. After most of the tracer plume has reached the depth monitored by both systems (i.e. below 0.4 m depth) there is a good consistency between the two datasets. Spatial moment calculations on the basis of ERT cannot be used to describe the movement of tracer alone, as the resistivity is affected by changes in both saturation levels and tracer concentration. Nevertheless, ERT appears to be an appropriate method to characterise regions of localised high infiltration in this type of soil. The method therefore constitutes a possible alternative and supplement to suction cups in a monitoring system.
Sammendrag
The susceptibility of Delia floralis eggs, neonates and larvae and the susceptibility of Galleria mellonella and Mamestra brassicae larvae to seven different Norwegian isolates of the insect pathogenic, hyphomycetous fungi Tolypocladium cylindrosporum, Metarhizium anisopliae and Beauveria bassiana, were investigated. Metarhizium anisopliae isolate ARSEF 5520 was highly virulent to G. mellonella larvae and caused 100% mortality when tested at a concentration of 3.6x106 conidia/ml. The same M. anisopliae isolate was not virulent to D. floralis larvae. Isolates of T. cylindrosporum, were equally virulent to G. mellonella and D. floralis causing up to 36.0% mortality of larvae. It is suspected, however, that the use of grated rutabaga as a food source in the D. floralis bioassay reduced the fungal virulence of both M. anisopliae and T. cylindrosporum to D. floralis. Among three T. cylindrosporum isolates tested at a concentration of 1.0x107 against eggs of D. floralis none of them reduced the hatching percentage. One isolate, ARSEF 5525 did, however, significantly reduce the longevity of neonates. Beauveria bassiana isolates ARSEF 5510 and ARSEF 5370 tested at a concentration of 1.0x107resulted in M. brassicae mortality levels of 70.0 and 55.0% respectively. The B. bassiana isolate ARSEF 5557, however, was not virulent to M. brassicae. Among the three isolates tested against M. brassicae the two virulent isolates produced a red pigment, probably oosporein, when cultured in Sabouraud dextrose agar.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
I 1998 ble angrep av soppsjukdommen greindød (Godronia cassandrae f. sp. vaccinii) vurdert i 51 felt med hageblåbær (Vaccinium corymbosum) i Sør-Norge. Soppen angriper og dreper hovedsakelig unge, uforvedete skudd, og infeksjonen skjer oftest ved basis av skuddene. Det utvikles rødbrune, avlange flekker hvor det etter hvert dannes svarte sporehus i konsentriske ringer. Til sammen 31 sorter var med i undersøkelsen. Det var store forskjeller i mottakelighet hos de ulike sortene. "Bluetta", "Goldtraube", "Hardyblue" og "Patriot" var de mest motstandsdyktige sortene, mens "Blueray", "Jersey" og "Earliblue" var de svakeste sortene.
Forfattere
V. Kilde Kjell VadlaSammendrag
Det er ikke registrert sammendrag