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
Authors
Solveig HaukelandAbstract
Entomopathogenic nematodes (EPNs) are commercially available for control of soil dwelling larvae of the vine weevil (Otiorhynchus sulcatus). In Europe several products are available comprising three different species, Heterorhabditis bacteriophora, H. megidis, and Steinernema kraussei. The latter species is for use at low temperatures. Results from several trials using H. megidis and S. kraussei against vine weevil in strawberry fields indicate that low temperature, soil type and possibly the application method are limiting factors that appear to reduce their efficacy. The use of EPNs against vine weevil larvae in the field will be discussed including results from cold-activity studies and application methods.
Abstract
Different methods to reduce the population of Arion lusitanicus are being investigated in private gardens naturally infested with the slug. In the laboratory the effect of different mulches are also being tested. Preliminary results from the studies conducted in gardens indicate that physical removal of slugs by picking or trapping and killing is most effective. In arenas in the laboratory, slugs avoided cocoa chips mulch and alginate granules. These studies are on-going and will be completed at the end of 2008. The slug parasitic nematode Phasmarhabditis hermaphrodita has recently been isolated in Norway. It is being studied as a biological control agent of A. lusitanicus. Results so far show that young slugs (0,02 " 0,04g) are most susceptible to infection and death. It also appeared that soil based bioassays gave better and more consistent results than assays using Petri dishes with filter paper. Further studies on the host-parasitic relationship of the nematode and slug are required.
Lecture – Sulfonylurea resistance found in several weed species in Norway
Jan Netland, Kjell Wærnhus
Authors
Jan Netland Kjell WærnhusAbstract
Det er funne sulfonylurea resistens i balderbrå, då, stivdylle, linbendel og vassarve. Resistent vassarve er vanlegast.
Authors
Jan Netland Kjell WærnhusAbstract
Sulfonylurearesiatens funne i 5 ugrasrter: Balderbrå, då, linbendel, stivdylle og vassarve
Authors
Trond HofsvangAbstract
Søramerikansk minerflue er siden 1995 funnet flere ganger i norske veksthus. Arten har hittil ikke etablert seg i Norge, da alle fluer funnet i veksthus er utrydded.
Authors
Solveig HaukelandAbstract
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.
Authors
Helge SjursenAbstract
Tradisjonelt er grønngjødslingseffekten den viktigste årsaken til å benytte kløver underkultur i korn. I flere omfattende forsøk har vi imidlertid nå studert hvordan bruk av underkultur i korn påvirker veksten til både ett- og flerårig ugras.
Authors
Arild Andersen Agnethe Christiansen Annette Folkedal Schjøll Solveig Haukeland Gunnhild Jåstad Richard Meadow Anette Sundbye Nina TrandemAbstract
Det er ikke registrert sammendrag
Authors
Christer Magnusson Karl Thunes Hans Nyeggen Hans Overgaard Trond Rafoss Solveig Haukeland May Bente Brurberg K. A. Strandenæs Bjørn Økland Bonsak HammeraasAbstract
The detection in 1999 of the pine wood nematode (PWN), Bursaphelenchus xylophilus, in Portugal triggered survey activities in many European countries. With the assumption that PWN would reach frequency 10 times lower than the native B. mucronatus and the requirement of a 95 % confidence limit suggested 2 995 samples to be required for a safe statement on the absence of PWN from the territory surveyed. Samples were taken from 10 circular areas with 50 km diameter erected from a point of import of risk materials. In the period 2000-2006 3 165 wood samples, 2 880 from Pinus sylvestris, 279 from Picea abies and 6 from unknown wood, were collected from 446 logging sites, in 84 municipalities and 13 counties. Of the total material 85 % of the samples came from cutting wastes, timber or lying trees. Wood showing signs of insect activity (incl. Monochamus) formed 73 % of the total material. Nematodes were recorded in 85 % of the samples. The order Rhabditida was most frequent, followed by the orders Aphelenchida, Tylenchida and Dorylaimida. Rhabditid nematodes were equally frequent in pine and spruce, while Aphelenchida (Aphelenchus, Aphelenchoides, Cryptaphelenchus, Seinura and Bursaphelenchus) and Tylenchida (Filenchus, Lelenchus, Ditylenchus, Deladenus and Nothotylenchus) tended to be more common in pinewood. Aphelenchoides was the most common genus. The genus Bursaphelenchus occurred in 1 % of the samples. B. mucronatus was detected in 0,3 % of the samples and most often in cutting waste of pine. The pine wood nematode (PWN), B. xylophilus, was not detected in this survey. The unexpected low natural occurrence of B. mucronatus indicates that the number of potential niches for PWN also is lower than expected, and hence it will be necessary to continue this surveillance program to reach 10 000 samples. The present zone sites in central and south-eastern Norway will be supplemented with 1-2 zone sites in southwestern region of the country. In the future these zone sites will function as permanent observation areas. Care will also be taken to collect all samples from detached wood with signs of Monochamus activity.
Abstract
Host tree terpenes can influence attraction of conifer-infesting bark beetles to their aggregation pheromones, and both synergistic and inhibitory effects have been reported. We tested a gradient of ratios of (–)-α-pinene, the predominant monoterpene in Norway spruce, to the pheromone of Ips typographus, a major pest of Norway spruce. Attraction of I. typographus increased as the release rate of (–)-α-pinene increased. The two highest (–)-α-pinene : pheromone ratios (526 : 1 and 2595 : 1) attracted twice as many I. typographus as pheromone alone, whereas low to intermediate ratios (56 : 1, 274 : 1) did not differ from pheromone alone. Our results are in agreement with a proposed model, which suggests that bark beetles display unique response profiles to host terpenes depending on the physiological condition of the host trees that they typically colonize. Ips typographus, which is an aggressive species capable of colonizing and killing healthy trees, showed an increased attraction to monoterpene : pheromone ratios, and this may be high enough to inhibit attraction of less aggressive beetle species typically colonizing dead, dying or stressed trees. Attraction of associates of I. typographus was also modified by (–)-α-pinene. Ips duplicatus, a competitor of I. typographus, showed increased attraction to the pheromone of I. typographus across all concentrations of (–)-α-pinene.