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.
2010
Forfattere
Kirsten TørresenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Kirsten TørresenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Etter en økning av barkbillenivået over flere år viser fellefangstene for 2010 en gjennomgående nedgang for hele landet. Dette kan trolig forklares med en våtere og kjøligere sesong sammenlignet med de foregående årene. Den viktigste perioden for flukt og formering av billene har hatt lavere temperatur og høyere nedbør enn normalen i store deler av områdene som dekkes av barkbilleovervåkingen. I Hedmark ser vi likevel noe økning av abarkbillenivået og flyregistreringer viser forekomst av drepte trær i noen kommuner både i 2009 og 2010. I nordlige lokaliteter med en del drepte trær i 2009 (Tydal) ser vi nå en markert nedgang i barkbillenivået.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Haukeland Solveig 1, Kalinga, Yonna 2, Mwatawala Maulid.2 & Maerere Amon.2 1Bioforsk, Norwegian Institute for Agricultural and Environmental Research, Høgskoleveien 7, 1432 Ås, Norway. solveig.haukeland@bioforsk.no 2Sokoine University of Agriculture, Department of Crop Science and Production, P.O. Box 3005 Morogoro, Tanzania. Yonna Kalinga, kalingaye@yahoo.co.uk, Maulid Mwatawala, mwatawala@yahoo.com and Amon Maerere, maerere@yahoo.co.uk Among the most important insect pests in fruit production in Tanzania are fruit flies (Diptera: Tephritidae) these include Bactrocera spp., Ceratitis spp. and Dacus spp. that can significantly reduce yield and fruit quality. Management of fruit flies include cultural control measures such as collecting and destroying infected host fruits, regulatory control (quarantine) and the use of insecticide baits. The best approach for control of fruit flies is to develop an IPM system that include several strategies to reduce the build up of damaging pest populations. Biological control agents such as entomopathogenic nematodes (EPN) are potential candidates within such a system. Naturally occurring EPN isolates in the genera Steinernema and Heterorhabditis have been isolated from a fruit growing area in the Morogoro region in Tanzania. Selected EPN isolates have been tested against larval and pupal stages of three important fruit fly species, Bactrocera invadence, B. cucurbitae and Dacus bivittatus. Results are promising and show that several isolates caused 70% to 90% mortality of larvae for all three fruit fly species. Laboratory studies on the ecological characteristics of selected EPN were also conducted using Galleria mellonella as host.
Sammendrag
Haukeland Solveig and Sundbye Anette The slug parasitic nematode Phasmarhabditis hermaphrodita is commercially available for slug control in many European countries and is mainly used in home gardens against the grey field slug Deroceras reticulatum. In some European countries it is used against the invasive slug pest Arion lusitanicus. The standard application method for using P. hermaphrodita is by surface application at a rate of 300 000 nematodes per square meter. Several studies have shown that A. lusitanicus individuals above 1 gram are not affected by P. hermaphrodita and field experiments indicate that this standard application method does not significantly reduce slug populations. Traditional molluscicides include an attractant, often wheat based packed around an active chemical ingredient. A slug baiting method, using P. hermaphrodita as the active ingredient, might be a better approach for biological control of slugs rather than surface application. We therefore decided to test the effect of P. hermaphrodita treated baits in laboratory and field studies. Laboratory experiments suggest this approach as promising, also against slugs above 1 gram. Results from ongoing field experiments will be presented and discussed.
Sammendrag
Docks are among the most important perennial weeds in grasslands throughout the world and the need for more effective control methods is especially crucial in organic forage production. To find more effective control methods, field trials over 2 years at 4 Norwegian locations, were carried out mainly as a full-factorial design, including factors expected to reduce docks significantly. (i) Date of grassland establishment: may be important for preventing/decreasing the flush of seedlings from seeds as well as shoots from root fragments.(ii) False seedbed preparation: to decrease soil seed bank. (iii) Use of nurse crop (cover crop) to increase competitiveness against Rumex seedlings. (iv) Cutting the taproot, using a rotary tiller before ploughing, or the "dock-plough" (a skimmer modified to cut roots in the entire furrow width at ca 7 cm depth): as new shoots mostly come from the neck and the upper 5 cm of the taproot. (v) Ploughing depth and skimming: to decrease shoots from root fragments. Weed development was assessed as the number of emerging Rumex seedlings and plants sprouting from root fragments. Results indicated that frequently more plants emerged from seeds than from root fragments. Neither renewing the grassland in summer, nor the use of the rotary tiller or the "dock plough" reduced the number of docks in the renewed grasslands. The use of the false seedbed and nurse crop, at some locations and years, reduced the number of docks in the renewed grasslands. Deep ploughing (24cm) reduced the number of Rumex plants from roots by 65% percent compared to shallow ploughing (16cm). Furthermore, the use of a skimmer reduced the number of docks sprouting from roots by 28%. Among the investigated factors, competitiveness, false seedbed and ploughing depth, as well as ploughing quality, seems to be the most promising factors for reducing the number of docks in renewed grassland.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Om dispensasjonen for Coragen mot rognebærmøll og planlagte forsøk iår. Dyrkere oppfordres til å la 4-5 trær være usprøytet.