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
Forfattere
Nils-Otto KitterødSammendrag
Hensikten med denne rapporten er å gi hydrogeologisk bakgrunnsmateriale til Bergen kommune i saksbehandlingen av det planlagte garasjeanlegget i Fløyfjellet. Basert på foreliggende informasjon er det beregnet sannsynlige effekter av en ny tunnel på vannbalansen i løsmassene ved Bryggen. Dersom vannlekkasjene i den nye tunnelen blir i samme størrelsesorden som i den eksisterende jernbanetunnelen, vil grunnvannssenkningen i løsmassene ved Bryggen bli meget beskjedne i forhold til de naturlige variasjonene i grunnvannstanden. Med de forutsetningene som er lagt inn i strømningsmodellen vil sannsynlige senkninger av grunnvannstanden bli i størrelsesorden 5 % av gjennomsnittlig naturlig grunnvannstand. Dette tilsvarer i underkant av 2 cm i forhold til gjennomsnittlig naturlig grunnvannstand nær kaikanten.
Forfattere
Nils-Otto KitterødSammendrag
Denne rapporten sammenstiller eksisterende kunnskap om hydrogeologiske forhold i nedbørsfeltet til Bryggen i Bergen. Det er lagt vekt på informasjon som er viktig for å forstå grunnvannstrykket og strømningsforholdene i Fløyfjellet. Kunnskapssammenstillingen vil danne utgangspunkt for numeriske eksperimenter hvor hensikten er å simulere endringer i grunnvannstrykket som kan oppstå ved konstruksjon av nye fjellanlegg i Fløyfjellet. Grunnvannstrykket i fast fjell er en av faktorene som bestemmer vannbalansen i løsmassene i Middelalderbyen i Bergen. Grunnvannet i fast fjell i nedbørsfeltet til Bryggen er lite undersøkt. Det foreligger imidlertid en god del indirekte informasjon som kan benyttes for å avgrense problemet og som dessuten kan benyttes for å anslå størrelsesorden på viktige inngangsparametre til numeriske beregninger. Hensikten med dette notatet er å sette foreliggende informasjon i sammenheng og dermed beskrive strømningsforholdene gjennom en begrepsmessig modell.
Forfattere
Bjørn FrantzenSammendrag
Omhandler entusiasten Piotr Zaborchikov sine private restaureringsarbeider knyttet til gamle trebygninger i landbyen Varzuga i Terskij kommune, Murmansk fylke i Russland på sørsiden av Kolahalvøya, en pomorlandsby ved Kvitsjøens kyster. På engelsk og russisk.
Forfattere
Ricardo HolgadoSammendrag
I verdensmålestokk er potetcystenematoder (PCN) (Globodera spp.) Kjent som alvorlige skadegjørere på potet. Nematodenes sterke spesialisering til potet som vertsplante har ført til en overlevelsesevne i jord som er stor utfordring for potetdyrkingen. Virulente populasjoner som kan oppformeres på resistent potet er en annen grunn for bekymring. Både den gule arten (yPCN) G. rostochiensis og den hvite arten (wPCN) G.pallida er klassifisert som karanteneskadegjørere og er regulert i Matloven. Bekjempelse av ikke virulent (yPCN) bygger på vekstskifte med resistent potet, ikke-vertsplanter og mottakelig potet. Bekjempelse av wPCN gjøres i dag ved at infiserte bruksenheter legges i karantene i 40 år med dyrkingsforbud for vertsplanter og annen aktivitet som risikere å sprede nematoden.
Forfattere
Sonja KlemsdalSammendrag
Det er ikke registrert sammendrag
Forfattere
Ricardo Holgado Anette Stryken Christer Magnusson Irene Rasmussen Kari-Ann Strandenæs Bonsak HammeraasSammendrag
A survey was undertaken to investigate the occurrence of plant parasitic nematodes in the municipality of Lier located in southern Norway. A wide variety of vegetables crops are grown in this area. Soils in Lier are mostly sandy loam, and irrigation is practiced when necessary during the growing season. There is little information on the occurrence on plant parasitic nematodes in vegetables; particularly in areas where farmers have specialized in intensive production, and often grow two to three cultures of vegetables during the growing season. In the year prior to this investigation several crops had been observed with symptoms of attack by plant parasitic nematodes. The aim of this survey was to identify the species responsible for the damage. The emphasis was placed on genera of known economic importance. During the end of the growing season plants showing poor growth or symptoms of nematode damage and plants with healthy appearance were sampled. A total of 74 root samples were collected and assessed for galls and 37 soil samples were collected from the rhizospheres. In the study samples were collected from 7 producers. Five samples were taken from cauliflower (Brassica oleraceae var. botrytis), 4 from broccoli (Brassica oleraceae var. italica), 8 from pak-choy Chinese cabbage (Brassica rapa ssp. pekinensis), 8 from lettuce (Lactuca sativa) and 1 from celery (Apium graveolens). Soil sampling included 11 samples from areas with fallow, ploughed and rotocultivated land. Root knot nematodes were not recorded in the root samples. In soil samples economically important nematode genera were recorded. Tylenchorhynchus sp. (72.9 % of samples), was the most frequently encountered genus, followed by the species Heterodera cruciferae and other Heterodera spp. (67.5 %), Pratylenchus spp. (54 %), Paratylenchus spp. (29,7 %), and Helicotylenchus spp. (8.1 %). In addition to cyst detections Heterodera juveniles were found in 32.4 % of samples. In all the samples from Pak-choy Chinese cabbage (Brassica rapa ssp. pekinensis) Heterodera cruciferae was recorded, symptoms of nematode damage was also observed in the field. The results of the survey will help in planning future research as well as in developing effective nematode management strategies suitable for vegetable producer particularly in this area. The authors are thankful to the FMLA in Buskerud County for economical support.
Forfattere
Ricardo Holgado Anette Stryken Christer Magnusson Irene Rasmussen Kari-Ann Strandenæs Bonsak HammeraasSammendrag
A survey was undertaken to investigate the occurrence of plant parasitic nematodes in the municipality of Lier located in southern Norway. A wide variety of vegetables crops are grown in this area. Soils in Lier are mostly sandy loam, and irrigation is practiced when necessary during the growing season. There is little information on the occurrence on plant parasitic nematodes in vegetables; particularly in areas where farmers have specialized in intensive production, and often grow two to three cultures of vegetables during the growing season. In the year prior to this investigation several crops had been observed with symptoms of attack by plant parasitic nematodes. The aim of this survey was to identify the species responsible for the damage. The emphasis was placed on genera of known economic importance. During the end of the growing season plants showing poor growth or symptoms of nematode damage and plants with healthy appearance were sampled. A total of 74 root samples were collected and assessed for galls and 37 soil samples were collected from the rhizospheres. In the study samples were collected from 7 producers. Five samples were taken from cauliflower (Brassica oleraceae var. botrytis), 4 from broccoli (Brassica oleraceae var. italica), 8 from pak-choy Chinese cabbage (Brassica rapa ssp. pekinensis), 8 from lettuce (Lactuca sativa) and 1 from celery (Apium graveolens). Soil sampling included 11 samples from areas with fallow, ploughed and rotocultivated land. Root knot nematodes were not recorded in the root samples. In soil samples economically important nematode genera were recorded. Tylenchorhynchus sp. (72.9 % of samples), was the most frequently encountered genus, followed by the species Heterodera cruciferae and other Heterodera spp. (67.5 %), Pratylenchus spp. (54 %), Paratylenchus spp. (29,7 %), and Helicotylenchus spp. (8.1 %). In addition to cyst detections Heterodera juveniles were found in 32.4 % of samples. In all the samples from Pak-choy Chinese cabbage (Brassica rapa ssp. pekinensis) Heterodera cruciferae was recorded, symptoms of nematode damage was also observed in the field. The results of the survey will help in planning future research as well as in developing effective nematode management strategies suitable for vegetable producer particularly in this area. The authors are thankful to the FMLA in Buskerud County for economical support.
Forfattere
Peder LombnæsSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Sonja KlemsdalSammendrag
The detection and quantification of plant pathogens in soil can be used to predict the risk to develop disease in the crop. Knowledge of the presence of such pathogens can also be used to plan control strategies for plant disease. The detection of carrot pathogens will be used as and illustrating example. Quality of carrots is influenced by several pathogens. In Norway the carrots are usually harvested in October, and while some carrots are used for immediate consumption, most carrots are stored shorter or longer periods in cold storage. During this storage there may be up to 70% loss due to carrot-rot caused by fungal diseases. The most important of these diseases are liquorice rot caused by the fungus Mycocentrospora acerina and crater rot caused by Fibularhizoctonia carotae. A standard PCR-based assay has been developed that enables us to detect the pathogens in the soil attached to the carrots at harvest. The results from this assay can be used to decide whether the harvested carrots can be stored or rather should be consumed immediately. Another disease, cavity spot, is worldwide considered to be one of the most economically important diseases of carrot. Multiple Pythium species are the cause of cavity spot and the importance of each species have been found to differ from one country to another. Five species of Pythium are the most important in causing cavity spot in Norway: P. violae, P. sulcatum, P. sylvaticum, P. intermedium and what is believed to be a new species, given the preliminary name P. "vipa". We have established standard PCR assays for the detection of all these five Pythium species in soil. These diagnostic assays have also been further developed to allow quantitative detection of these same pathogens by real-time TaqMan PCR. Such a test can potentially be used to analyze fields in order to avoid cropping carrots where the corresponding pathogens are found and the consequent risk of developing cavity spot is high. Another potential benefit for such a test might be to use the test result from a growing field of carrots to predict the need to spray this field with pesticides. The general experience is that it is difficult to extract "good" DNA from soil samples, and inhibition of the PCR reaction is often observed. DNA extraction protocols often need to be optimized to reduce the amount of compounds that otherwise would inhibit PCR, e.g. humic acid, as much as possible. Additional purification steps, dilution of the DNA samples and an adjusted mastermix might reduce the problems. Strategies to improve the PCR-based detection of plant pathogens in soil will be discussed.