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.
2006
Sammendrag
Methods for measuring prevalence of Neozygites floridana in a Tetranychus urticae population collected from strawberries were developed and compared. T. urticae were extracted from leaves using a soapy water solution (0.5 ml washing detergent : 8 l water) and then placed into 80% alcohol for use in methods 1 and 2. Method 1: N. floridana-sporulating T. urticae cadavers were observed and quantified under a compound microscope (40-80X). Method 2: Adult females were mounted in lactophenol cotton blue and observed for the presence or absence of N. floridana hyphal bodies under a microscope (200-400X). Method 3: Live T. urticae females were incubated at 25ºC and 75% RH and observed for mortality and N. floridana infection under a compound microscope (6.4-40X). Method 1 was the most time-efficient method and it also allows processing of samples as time permits. Method 2 quantified significantly higher fungal prevalence than method 1 and 3, but method 2 is not considered to be reliable because hyphal bodies are difficult to detect. No significant differences were found between methods 1 and 3.
Forfattere
Gudbrand Lien Ola Flaten Audun Korsæth K.D. Schumann J.W. Richardson Ragnar Eltun J. Brian HardakerSammendrag
Målet med denne studien var å jamføre risikoen for økologiske, integrerte og convensjonelle dyrkingssystem. Forsøksdata frå eit dyrkingssystem (1991-1999) på Austlandet vart brukte saman med budsjettal frå gardsbruk. Empirisk fordeling av nettoinntekt for ulike dyrkingssystem vart estimert ved hjelp av ein simuleringsmodell. Resultata syner at det økologiske systemet hadde størst variasjon i nettoinntekt, men med gjeldane tilskotsordningar og meirprisar for økologiske varer vert dette det mest økonomiske alternativet.
Forfattere
Linda Gordon Hjeljord Richard Meadow Annette Folkedal SchjøllSammendrag
Experiments were performed to determine the ability of the insect pathogenic hyphomycete, Metarhizium anisopliae, to germinate, grow and sporulate in the presence of Trichoderma atroviride. Trichoderma spp. includes mycoparasites commonly found in soil and used in biocontrol of plant diseases. When conidia of M. anisopliae and T. atroviride were coinoculated on agar media, T. atroviride overgrew M. anisopliae and prevented its establishment at temperatures from 6-30 oC. This effect was lessened when M. anisopliae and T. atroviride were inoculated at different points on the medium, giving the insect pathogen time to establish a colony and secrete antifungal metabolites. Although both fungi had growth optima at 25-30 oC, separately inoculated M. anisopliae was best able to compete with T. atroviride at temperatures " 18 oC, and the antibiosis zone was widest at 30oC. When M. anisopliae and T. atroviride were coinoculated onto black vine weevil larvae (Otiorhynchus sulcatus) at 20 oC, the ability of the insect pathogen to infect and kill the larvae and sporulate on the cadavers was not affected by the presence of T. atroviride conidia. These results indicate that while the virulence of M. anisopliae to the larvae was not reduced by T. atroviride, the ability of the insect pathogen to grow saprophytically and increase its inoculum could be reduced on substrates containing T. atroviride conidia.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Roy Browne Fabio Mascher Gabriela Golebiowska Ingerd Skow HofgaardSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Gunnhild Jåstad Berit Hovland Olav Opedal Sigrid Mogan Olav Sørum Endre Bjotveit Dag RøenSammendrag
Teger er eit viktig skadedyr i både økologisk og konvensjonell eple- og pæreproduksjon. Det er få tilgjengeleg tiltak mot teger i økologisk fruktdyrking. Forsøk med ulike direkte tiltak viste at NeemAzal er eit effekt tiltak mot teger i eple. Resultat frå ulik handsaming av undervegetasjonen som eit førebyggjande tiltak gav svært ulike resultat; i nokre felt førde hyppig slått av undervegetasjonen til mindre skade, medan slått i andre felt førde til meir skade. Eit pilotforsøk med insektpathogene sopp mot teger viste lovande resultat.
Sammendrag
Denne artikkelen beskriver forsøk med ulike sopparter (isolert fra jordbærplanter) som kunne ha et potensiale som nyttesopper (biologisk kontroll) mot gråskimmel i jordbær. Epicoccum nigrum og Aureobasidium pullulans ga redusert råtning (gråskimmel) et år, mens ingen av de potensielle nyttesoppene reduserte råtningen året etter.
Forfattere
Solveig HaukelandSammendrag
The black vine weevil (Otiorhynchus sulcatus) is an important pest in many crops in several countries worldwide. The adults feed on the leaves of strawberries, rhododendrons, azaleas and many other ornamental plants. Indoors, O. sulcatus can infest begonias, ferns, cyclamins, and other common container plants. Adult feeding does not seriously affect the plants, it is the larval feeding on roots of host plants that causes the most serious plant injury. Larvae may also girdle the main stem below the soil line. Leaves will yellow and plants may be stunted or die. O. sulcatus weevils are difficult to control once established because of their nocturnal behaviour and the subterranean habits of the larvae. In strawberries chemical control using a pesticide against the adult weevils after harvest is the most common control method today, however the most effective pesticides will shortly no longer be available and there are few alternative pesticides on the market. Fortunately there are Entomopathogenic nematodes (EPN) that can be used to control the soil dwelling larvae and in Europe there are several products on the market comprising three species (Heterorhabditis bacteriophora, H. megidis, and Steinernema kraussei). The use of these nematodes has shown to be quite successful in potted plants (in nurseries), whereas in field grown crops such as strawberry they are still not consistently effective. In this presentation results from a number of field trials using H. megidis and S. kraussei against O. sulcatus larvae infesting field grown strawberry will be presented and discussed.