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.
2007
Sammendrag
Neozygites floridana is an important natural enemy of the two-spotted spider mite, Tetranychus urticae. Pesticides used in strawberries that might affect the conservation and enhancement of this beneficial fungus were therefore studied. This was done in a laboratory study by letting non-inoculated (healthy) mites and mites inoculated with N. floridana feed on strawberry leaf disks treated with one of the following pesticides: the fungicides tolylfluanid, fenhexamid or cyprodinil + fludioxonil or the acaricide/insecticide/molluscicide methiocarb. The effect of these pesticides on mortality and egg production of T. urticae and on the killing capacity and sporulation of N. floridana were determined. Tolylfluanid increased the mortality of non-inoculated mites (75.3%) compared to the non-inoculated control (27.5%). Methiocarb also killed non-inoculated mites. Fenhexamid did not have any effect on the mortality of non-inoculated mites (19.2%), neither had cyprodinil + fludioxonil (19.1%). Tolylfluanid did not reduce the mortality of mites inoculated with N. floridana (89.3%) compared to the inoculated control (80.0%). Neither did methiocarb, it rather increased the mortality of inoculated mites (93.2%). Fenhexamid did, however, reduce the mortality of inoculated mites (66.7%). The same was true for cyprodinil + fludioxonil (48.7%). In addition, cyprodinil + fludioxonil increased the time to death of inoculated mites (6.69 days) compared to the control (6.10 days), and inhibited sporulation of N. floridana (7.9% sporulation) compared to the control (42.4% sporulation). Tolylfluanid also reduced sporulation of N. floridana (15.5% sporulation). Results from this study indicate that the use of the fungicides tested will potentially reduce the survival and efficacy of the natural enemy N. floridana in the field.
Forfattere
Thomas Hartnik Henning MatthiesenSammendrag
Piling as a foundation technique on cultural layers has the advantage that the amount of excavated material is reduced. On the other hand, piling can have an adverse impact on the preservation of cultural layers in the ground due to physical deterioration and by enhancing biological degradation. The study presented in this report aimed at assessing the effect of piling and associated construction techniques on the environmental conditions in cultural layers that control biological degradation. Physical and chemical investigations in two excavated soil profiles near Hotel Klubben in Tønsberg were performed where piling was used as a foundation technique, and where drillings had earlier indicated a reduced organic content and worse state of preservation of the deposits close to the pile. Environmental conditions were assessed conducting field and laboratory measurements of basic physical and chemical parameters, as well as measurements of redox sensitive parameters. The results of the measurements revealed high oxygen concentrations near the foundation wall of the building where the cultural layers had been exchanged by porous fill masses. While areas that were not affected by oxygen intrusion had iron and sulphate reducing conditions that represent good preservation conditions in cultural layers, redox conditions near the building were aerobic and nitratereducing. These conditions enhance degradation of cultural layers. Oxygen intrusion into the ground is most likely facilitated by coarse material that was refilled next to the building when a girder was built under the foundation walls of the building. This coarse material enables diffusion of air into cultural layers as well as percolation of oxygen rich rain water into the ground . A possible adverse effect of the pile on environmental conditions is totally overshadowed by the effect of the girder and refilling material and could not be detected. It was not possible to investigate the conditions closer than approximately 50 cm from the pile. Nor was it possible to investigate the conditions deeper than 2.2 m beneath the soil surface, and thus this report cannot conclude anything about the conditions and possible impacts outside the investigated area.
Forfattere
Thomas Hartnik Henning MathiessenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Seks fôringsforsøk ble gjennomført for å undersøke ulike fôringsstrategier for melkekyr i økologisk landbruk. Ulike konserveringsmetoder for bygg, ulike utviklingstrinn av grassurfôr og ulike proteintilskudd hadde ingen effekt på melkas sensoriske kvalitet. Fiskemel ga ingen avvik fra normal melkesmak selv når det ble fôret to timer eller en halv time før kveldsmelking.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Eivind Vangdal Aksel Døving Finn MågeSammendrag
Samanhengen mellom avling, klima og fruktkvalitetsfaktorar vart undersøkt i 11 plommesortar. Registreringar frå 1985 til 2003 viste i 8 av 11 sortar ein negativ samanheng mellom avling og oppløyst turrstoff. Syreinnhaldet var ikkje påverka av avlingsnivå. Inntil 44% av variasjonen i innhaldet av oppløyst turrstoff skuldast avlingsvariasjon. Ved å inkludera klimafaktorar i regresjonsanalysene kunne ein forklara frå 60 til 94% av variasjonen i oppløyst turrstoff med variasjon i avling og gjennomsnitts månadstemperatur og månadsnedbør. Innhaldet av oppløyst turrstoff var positivt påverka av høge temperaturar i april og juni, og kjølig og fuktig ver i mai. I år med mykje nedbør i august var innhaldet av titrerbar syre i plommene høgt.
Forfattere
Eivind Vangdal Finn Måge Aksel DøvingSammendrag
Det er ikke registrert sammendrag
Forfattere
Solveig HaukelandSammendrag
The large arionid slug Arion lusitanicus is a serious pest in parts of northern Europe including many parts of Norway. In Norway it has mainly been a pest in home gardens but in recent years it has also spread to horticultural and vegetable crops such as strawberry and lettuce. The use of the nematode Phasmarhabditis hermaphrodita against A. lusitanicus is being investigated in an on-going research project that was initiated in 2005. A survey was conducted in 2004 to examine if the nematode P. hermaphrodita could be found occurring naturally in Norway. The result of the survey was positive which led to registration of the product Nemaslug in 2005. Several experiments have been carried out since 2005, to study the effect of both the commercial product Nemaslug and Norwegian isolated P. hermaphrodita on A. lusitanicus slugs. Laboratory and controlled pot experiments confirm that young stages of the slugs are susceptible to the slug parasitic nematode. Further work on the infection process of nematodes in slugs as well as the practical aspects of nematode use in gardens and the field will be addressed as a next step in these studies.