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.
2004
Forfattere
Guro BrodalSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Insect pathogenic fungi and parasitoids are important control agents of aphids. In a survey in one conventional and four organic apple orchards in Norway insect pathogenic fungi and parasitoids as natural enemies of Aphis pomi and Dysaphis plantaginea were studied weekly in the summer 2002 and 2003. Four species of insect pathogenic fungi in the order Entomophthorales were observed in both apple aphid species: Entomophthora planchoniana, Neozygites fresenii, Erynia neoaphidis and Conidiobolus obscurus. The fungus N. fresenii caused an epizootic on A. pomi in one organic location and seemed to decrease the aphid population during the summer 2002. The highest mortality caused by fungal infection of A. pomi was 39,6 % and 33,3 % of D. plantaginea. Mortality caused by parasitoids was more important in A. pomi than in D. plantaginea and the highest parasitation recorded in A. pomi was 30 %. Four species of primary parasitoids hatched from A. pomi: Binodoxys angelicae, Lipolexis gracilis, Praon sp. and Ephedrus sp. Hyperparasitoids that hatched from A. pomi were: Dendrocerus carpenteri, Alloxysta pleuralis, Phaenoglyphis villosa and Asaphes suspensus. Only one individual of D. plantaginea was parasitized and this parasitoid was Ephedrus persicae.
Forfattere
Nina TrandemSammendrag
Bildequiz om insekter i bær (12 bilder). NB: Det har sneket seg inn en feil i fasiten til bilde nr 5. Det skal være stikkelsbær i stedet for bringebær (stikkelsbærveps angriper ikke bringebær).
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Gunhild Børtnes Erling BerentsenSammendrag
Dekking med fiberduk eller insektnett kan skjerme mot viktige skadedyr i kålvekste, men dekking i heile veksttida kan skape problemer for vekst og kvalitet. Dersom en ser bort fra at det kan være problemer med å få festet dekkemateriale godt til jorda vil type dekke være avgjørende for virkningen på avling og kvalitet. Dekking i løpe av sommeren med fiberduk (Agryl P 10), eller duk med tilsvarende egenskaper, førte i vårt forsøk til mindre rotavling, dårligere farge på skolten og nedsatte smaksegenskaper. Denne duken er trolig lite aktuell. Derimot så insektnett (Rantai) ut til å gi brukbart resultat både for kvalitet og avling.
Forfattere
Rachel A. Garbitt Karen Rae Bone Leslie J. ParentSammendrag
The Rous sarcoma virus Gag protein undergoes transient nuclear trafficking during virus assembly. Nuclear import is mediated by a nuclear targeting sequence within the MA domain. To gain insight into the role of nuclear transport in replication, we investigated whether addition of a "classical" nuclear localization signal (NLS) in Gag would affect virus assembly or infectivity. A bipartite NLS derived from nucleoplasmin was inserted into a region of the MA domain of Gag that is dispensable for budding and infectivity. Gag proteins bearing the nucleoplasmin NLS insertion displayed an assembly defect. Mutant virus particles (RC.V8.NLS) were not infectious, although they were indistinguishable from wild-type virions in Gag, Gag-Pol, Env, and genomic RNA incorporation and Gag protein processing. Unexpectedly, postinfection viral DNA synthesis was also normal, as similar amounts of two-long-terminal-repeat junction molecules were detected for RC.V8.NLS and wild type, suggesting that the replication block occurred after nuclear entry of proviral DNA. Phenotypically revertant viruses arose after continued passage in culture, and sequence analysis revealed that the nucleoplasmin NLS coding sequence was deleted from the gag gene. To determine whether the nuclear targeting activity of the nucleoplasmin sequence was responsible for the infectivity defect, two critical basic amino acids in the NLS were altered. This virus (RC.V8.KR/AA) had restored infectivity, and the MA.KR/AA protein showed reduced nuclear localization, comparable to the wild-type MA protein. These data demonstrate that addition of a second NLS, which might direct MA and/or Gag into the nucleus by an alternate import pathway, is not compatible with productive virus infection.
Forfattere
Frode VeggelandSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
The objective of the project was to evaluate the extension and reasons of pesticide contamination of drinking water wells in an area with intensive cultivation of potatoes and small grains on fluvial deposits. Most of the households in the field drinking water was supplied from simple groundwater wells, consisting of 5/4 - steel pipes with filter tips, hammered down to the groundwater zone. The area was assumed to be vulnerable to groundwater pollution as permeable deposits covered the major part of the area. High concentrations of pesticides had also been found in groundwater wells in a pilot project. In the project extension and causes of pesticide contamination of the drinking water wells have been assessed from: Soil properties, properties of deeper deposits, hydrogeology and groundwater flow, localisation and use of washing sites and agricultural practise, simulations of groundwater flow around washing sites and wells, simulations of diffuse pesticide leakage from soil and monitoring contents of pesticides and nitrates in groundwater samples from drinking water wells. The results show that most of the pesticide contamination to the groundwater in water could be explained by diffuse leakage from soil after application of normal doses of pesticides on the fields. Some few higher concentrations can be explained by point sources. The investigation supports the hypothesis that the high concentrations of metribuzin and metalaksyl in samples of drinking water in the pilot project, were caused by point source contamination from washing sites. Changes in the attitude among the farmers and procedure for spraying after increased focus on the risk of pesticide pollution might have caused a better procedure for handling of pesticides. The combination of washing sites and drinking water wells requires a high degree of attention and knowledge about pesticides, soil and water. Knowledge from the project has brought into focus the question; how to practice the approval and use of pesticides to reduce contamination. Should pesticides be given general approvals or whether approvals might include restrictions within areas with high risks of groundwater contamination. The last approach will move responsibility to the end-users and will also require adequate advisory tools and services.