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.
2008
Sammendrag
Arter innenfor bjørnekjeksslekta hører med blant de fremmede artene som i dag er i sterk spredning i kulturlandskapet. Fremmede arter utgjør en trussel mot det biologiske mangfoldet, fordi de fortrenger stedegne arter og forstyrrer lokale økosytemer. I denne fagartikkelen sammenstilles eksisterende kunnskap om bjørnekjeksslekta og de erfaringene man har med ulike tiltak for å bekjempe dem. I områder hvor bjørnekjeks skal bekjempes og der man samtidig ønsker å ivareta biologisk mangfold må spesielle hensyn tas.
Forfattere
Arild Andersen Thi Thien An Tran Einar NordhusSammendrag
Innsamling av polyfage Liriomyza-arter i felt i Vietnam ble gjennomført i 50 av Vietnams 62 provinser i 2002-2007. Mer enn 16 800 individer ble identifisert til art. L. sativae var den dominerende arten, og forekom vanlig i alle undesøkte provinser. L. huidobrensis ble funnet i 7 provinser omkring Da Lat. L. trifolii ble funnet i 13 provinser fra Ho Chi Minh City til Hue. L. bryoniae ble funnet i 15 provinser nord for Ho Chi Minh City. L. chinensis ble funnet i 20 provinser over hele landet. Dessuten ble Chromatomyia horticola funnet i 9 provinser fra provinsen Lam Dong og nordover, og L. katoi blir rapportert fra Vietnam for første gang. Sannsynlig videre spredning blir diskutert for de ulike artene.
Forfattere
Arild AndersenSammendrag
Det er kjent omkring 200 arter av minerfluer her i landet. Disse små fluene opptrer som skadedyr ved å ha larver inne i ulike plantearter, noe som fører til estetisk skade i prydvekster og nedsatt avling hos matplanter. Vanlige norske arter som havrebladminerflue på gras, Phytomyza ranunculi på soleier, Kristtornminerflue på kristtorn, Chromatomyia horticola på erter og Phytomya lonicerae på kaprifol blir behandlet.
Sammendrag
A major concern regarding use of velvet bentgrass (Agrostis canina L.) in Scandinavia is whether the current cultivars have sufficient winter hardiness. The objective of this study was to compare the tolerance of the four velvet bentgrass cultivars "Avalon", "Greenwich", "Legendary" and "Villa" to various types of winter stress with that of creeping bentgrass (Agrostis stolonifera L. ) "Penn A-4" under controlled conditions. To evaluate tolerance to freezing temperatures, unhardened and hardened plants were frozen at ar rate of 2°C per hour to -6, -9, -12 and -15°C. On average for two hardening conditions, all velvet bentgrass cultivars survived freezing marginally, but significantly better than `Penn A-4" (Table 1). Hardened plants had almost five times higher turf coverage than unhardened plants. Most plants survived freezing to -6°C, but hardly to -9°C, and not to -12°C and -15°C. A significant cultivar x hardening interaction indicated that `Greenwich" had higher freezing tolerance then the other cultivars only in the unhardened state To test tolerance to ice cover, snow cover and/or pink snow mould, unhardened and hardened plants were either unsprayed or sprayed with a mycelial suspension of Microdochium nivale and then incubated for 6 or 12 weeks in darkness at 0.5-1.0°C, either uncovered or enclosed in air-tight vacuum bags (simulating anaerobic conditions under ice cover), or covered with a sheet of wet cotton and wrapped in plastic (simulating snow cover). As a main effect, `Penn A-4" survived these winter conditions better than the velvet bentgrass cultivars. Among the velvet bentgrasses, winter survival of `Avalon" was inferior to that of `Villa", `Legendary" and `Greenwich". Better survival of `Penn A-4" was primarily due to better tolerance to M. nivale (Figure 2), not to ice or snow cover.
Forfattere
Ellen Johanne SvalheimSammendrag
Grenda Åraksbø er foreslått som utvalgt kulturlandskap for Aust-Agder. I grenda er det registrert en rekke kulturminner, og flere verdifulle naturtypelokaliteter med kulturavhengige arter er også registrert. Denne forvaltningsplanen vektlegger driften av landskapet og naturverdiene innen området. Spesielt legges det vekt på skjøtsel av de verdifulle biomangfoldlokalitetene.
Sammendrag
Det finnes mange soppmidler (fungicider), men bare noen av dem er tillatt brukt i grøntanlegg. Endringer kan skje fra år til år. Plantevernmidler blir som regel godkjent for en 5-års periode før de revurderes av Mattilsynet. Oversikt over hvilke plantevernmidler som er tillatt brukt i norske grøntanlegg finnes i Plantevernguiden. Nyttige opplysninger er også tilgjengelige i Plantevernleksikonet og i preparatlister fra Mattilsynet. Se link til disse kildene i teksten under.
Sammendrag
Aerial dispersal of inoculum is critical to the spread of many plant diseases; including potato late blight (Phytophthora infestans (Pi)), lettuce downy mildew (Bremia lactucae (Bl)) and cucurbit downy mildew (Pseudoperonospora cubensis (Pc)). In addition to relative humidity and temperature, spore survival during aerial dispersal is affected by solar irradiation (SI), in particular during long-distance transport at higher altitudes. We evaluated the potential survival of spores in air by placing detached spores of Pi, Bl and Pc on filter paper in either direct sun or shade at time intervals from 0.5 to 3 h (Pi and Bl), or up to 42 hours (Pc). Thereafter, the filter papers were placed in moist chambers for 15 min prior to incubation on pea agar (Pi) or water agar (Bl and Pc) for 24 h, before the viable spores were enumerated. Spores were considered viable if they exhibited a germ tube or released zoospores. Preliminary results show that no spores of Pi, Bl and Pc germinated after 1, 3 and 30 h exposure to direct sun, with critical SI doses near 700, 2000 and 8500 Wm-2, respectively. In shade, no Pi spores germinated after 3 h, while spores of Bl and Pc were still viable after 3 and 42 h, respectively. In Norway, the potential for long distance distribution of Pi is restricted, but more likely for Bl and Pc. Further experiments will be conducted to find the maximum survival time for spores of these pathogens under Norwegian climatic conditions.
Sammendrag
Aerial dispersal of inoculum is critical to the spread of many plant diseases; including potato late blight (Phytophthora infestans (Pi)), lettuce downy mildew (Bremia lactucae (Bl)) and cucurbit downy mildew (Pseudoperonospora cubensis (Pc)). In addition to relative humidity and temperature, spore survival during aerial dispersal is affected by solar irradiation (SI), in particular during long-distance transport at higher altitudes. We evaluated the potential survival of spores in air by placing detached spores of Pi, Bl and Pc on filter paper in either direct sun or shade at time intervals from 0.5 to 3 h (Pi and Bl), or up to 42 hours (Pc). Thereafter, the filter papers were placed in moist chambers for 15 min prior to incubation on pea agar (Pi) or water agar (Bl and Pc) for 24 h, before the viable spores were enumerated. Spores were considered viable if they exhibited a germ tube or released zoospores. Preliminary results show that no spores of Pi, Bl and Pc germinated after 1, 3 and 30 h exposure to direct sun, with critical SI doses near 700, 2000 and 8500 Wm-2, respectively. In shade, no Pi spores germinated after 3 h, while spores of Bl and Pc were still viable after 3 and 42 h, respectively. In Norway, the potential for long distance distribution of Pi is restricted, but more likely for Bl and Pc. Further experiments will be conducted to find the maximum survival time for spores of these pathogens under Norwegian climatic conditions.
Forfattere
Bjørn Molteberg Trygve S. Aamlid Frank Enger Anne A. Steensohn Åge SusortSammendrag
From 2003 to 2006, three varieties of velvet bentgrass (Agrostis canina), thirteen varieties of creeping bentgrass, nine varieties of colonial bentgrass (Agrostis capillaris), four varieties of slender creeping red fescue Festuca rubra var. trichophylla): thirteen varieties of chewings fescue (Festuca rubra var. commutata), and one variety of annual bluegrass (Poa annua var. reptans) were evaluated for establishment rate, overall turf quality (visual merit), tiller density, color, leaf fineness, per cent living plant cover, winter injury, disease resistance, spring green-up, daily height growth, and thatch accumulation in trials on USGA-spec. putting greens at the Bioforsk research stations Landvik (58°N, 12 m a.s.l.) and Apelsvoll (61°N, 250 m a.s.l.) in south-east Norway. These experimental sites are considered representative for the southern/coastal and the northern/ continental zone of Scandinavia, respectively. The trials were mowed three times per week to 3 mm for bentgrass species and annual bluegrass and to 4-5-5.0 mm for red fescues; fertilized with easily soluble, small-grain mineral fertilizer every second week, and otherwise managed as putting greens with respect to irrigation, vertical mowing, aeration and topdressing. The greens were not open to regular play, but articifial wear was imposed by rolling friction-drums with golf-spikes over the trials three timers per week. On average for varieties within each species, velvet bentgrass had the highest visual merit scores at both experimental sites. Velvet bentgrass had higher density and finer leaves than any other species in the study. Along with colonial bentgrass, it also had better winter survival than creeping bentgrass, red fescue and annual bluegrass. The main disadvantage of velvet bentgrass is its rapid formation of thatch; this problem must be resolved before a general recommendation for use of velvet bentgrass on Scandinavian putting greens can be given. Next to velvet bentgrass, colonial bentgrass and creeping bentgrass were ranked as the most suitable species for golf courses in the northern/continental and southern/coastal zone, respectively. Red fescues should be preferred on golf courses not using fungicides and with limited maintenance budgets. While annual bluegrass `True Putt" cannot be recommended for putting greens in any part of Scandinavia, the ranking of varieties within each species depended, for the most part, on climatic zone. Based on overall performance in this project, a list of recommended varieties are presented for the Scandinavian putting greens.
Forfattere
Stein Rune Karlsen Anne Tolvanen Eero Kubin Jarmo Poikolainen Kjell Arild Høgda Bernt Johansen Fiona S. Danks Paul Eric Aspholm Frans Emil Wielgolaski Olga MakarovaSammendrag
Northern Fennoscandia is an ecologically heterogeneous region in the arctic/alpine-boreal transition area. Phenology data on birch from 13 stations and 16-day MODIS-NDVI composite satellite data with 250 m resolution for the period 2000 to 2006 were used to map the growing season. A new combined pixel-specific NDVI threshold and decision rule-based mapping method was developed to determine the onset and end of the growing season. A moderately high correlation was found between NDVI data and birch phenology data. The earliest onset of the growing season is found in the narrow strip of lowland between the mountains and the sea along the coast of northern Norway. The onset follows a clear gradient from lowland to mountain corresponding to the decreasing temperature gradient. In autumn, the yellowing of the vegetation shows a more heterogeneous pattern. The length of the growing season is between 100 and 130 days in 55% of the study area.