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.
2004
Forfattere
Nina Elisabeth Nagy Carl Gunnar Fossdal Paal Krokene Trygve Krekling Anders Lönneberg Anders Lønneborg Halvor SolheimSammendrag
Polyphenolic parenchyma cells (PP cells) in Norway spruce (Picea abies (L.) Karst.) stem phloem play important roles in constitutive and inducible defenses. To determine whether anatomical and molecular changes in PP cells are correlated with tree resistance, we infected two Norway spruce clones with the pathogenic fungus Ceratocystis polonica (Siem.) C. Moreau. The fungus induced significantly different lesion lengths in the two clones, indicating that one clone was more resistant to the fungus (short lesions) than the other (long lesions). After infection, the cross-sectional area of PP cells and their vacuolar polyphenol bodies increased in the three most recent annual rings of PP cells in both clones. The more resistant clone had larger PP cells with denser polyphenol bodies than the less resistant clone, whereas the less resistant clone accumulated relatively more polyphenols after infection. Compared with the less resistant clone, the more resistant clone contained higher starch concentrations before infection that were reduced more quickly after infection before returning to original values. Low transcript levels of chalcone synthase were detected in uninfected tissues of both clones, but the levels increased dramatically after infection. Transcript levels were higher and peaked 6 days earlier in the more resistant clone than in the less resistant clone. The activity of at least one highly basic peroxidase isoform was greatly enhanced after infection, and this increase occurred earlier in the more resistant clone.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Sissel Torre Päivi Rinne Carl Gunnar Fossdal Heather Danforth Stein Erik Lid Ragnhild Nestestog Chris Van der SchootSammendrag
Det er ikke registrert sammendrag
2003
Forfattere
Lars Sandved Dalen Jonathan Watkinson A. A. Sioson V. Singal D. Kumar N. Ramakrishnan L.S. Heath Carl Gunnar Fossdal Ruth GreneSammendrag
Trees cover over one-third of the world's land area and carry out about two-thirds of global photosynthesis. Coniferous forests cover 1.2 billion hectares of Alaska, Canada, Scandinavia, and Russia, and comprise one-fourth of the world's boreal and temperate forests. More than 50% of Scandinavia's land area consists of forests, mostly coniferous. Information about the molecular responses in trees to biotic and abiotic factors is therefore of great importance - both scientifically and practically.Transcript regulation in response to drought stress was investigated for Norway spruce (Picea abies) with microarrays including 1,700 cDNAs from 5 EST libraries from Pinus taeda and analyzed using the Expresso Microarray Management System.In order to verify the level of drought stress, we measured the physiological status of the plants. After four days of drought, chlorophyll fluorescence was reduced by 6% and after eight days by over 40 %, compared to the control. Hybridizations of spruce RNA to microarray slides was used to probe for changes in transcripts from two to eight days after watering stopped.Monitoring of transcript levels was accomplished by hybridizing spruce cDNA to the 1700 element microarrays. After two days of drought, circa 2 % of the transcripts in Norway spruce were significantly upregulated and 7 % were downregulated. At the end of the experiment after eight days of drought needle chlorophyll fluorescence was reduced by 40 % compared to the control, and 6 % of the transcripts were upregulated and 12 % of the transcripts were downregulated. Results from inductive logic programming are also presented.
Sammendrag
Jordbærdyrking i Nord-Norge stiller store krav til sortsmaterialet. Vanskelige overvintringsforhold og korte, kjølige og våte somre opptreder opptrer i mer ekstrem grad enn i sør. For å sikre årviss produksjon trenger vi nye sorter, som har bedre overvintringsevne og som har faste bær, som tåler både regn, fuktighet, håndtering og transport. Hovedsorter i Nord-Norge er "Zefyr" og "Korona". "Glima" er en populær tidligsort. "Polka" er på vei frem. I artikkelen gis en oversikt over styrker og svakheter for disse og andre aktuelle sorter for Nord-Norge. Nytt sortsmateriale fra Planteforsk sitt foredlingsprogram er på vei ut til dyrkerne. To sorter; "Carmen" og "Aurora" er nu under verdiprøving. Av disse har Carmen gitt gode resultater i forsøksfelt på Planteforsk Vågønes/ Bodø, mens Aurora viste svak overvintring og gav dårlig utbytte. Ytterligere seks lovende kloner et uttatt til videre utprøving.
Forfattere
Jahn DavikSammendrag
Aurora" og "Carmen" bør prøves i begrenset omfang hos dyrkere før den eventuelt oppformeres for alminnelig salg. "Polka" ser ut til å være mer produktiv enn "Korona", men det er en ulempe at "Polka" etter hvert utvikler en lite tiltalende plante. Verdiprøvingsfeltene på Kise har vist at "Korona" holder stand der. To nye sorter "Florence" og "Frida" kan imidlertid vise seg som utfordrere. "Florence" har blitt godt mottatt i forbrukertester, mens "Frida" ser ut til å være meget produktiv. Mer erfaring vil nok akkumuleres fra disse sortene etter hvert. Fra jordbærforedlingen i Planteforsk ligger de an til at fire nummersorter vil bli oppformert for begrenset utprøving.
Sammendrag
Forekomsten av Pythium spp. og Phytophthora spp. i norske veksthus med dyrking av grønnsaker i vannkultur, ble undersøkt i perioden 1990-1995. I tomat og salat var Phytophthora cryptogea den vanligst forekommende arten. I agurk, den mest undersøkte kulturen, var Pythium gruppe F og Pythium irregulare de to dominerende arter. Phytophthora ble ikke funnet på agurk. Patogeniteten til de isolatene som forelå fra undersøkelsen, ble testet på frøplanter av agurk. De mest agressive artene var Pythium aphanidermatum, Pythium ultimum, Pythium paroecandrum og Pythium irregulare.
Sammendrag
During a period of five years (1998 - 2002), 26 strawberry cvs and 5 selections were tested for resistance to crown rot. Cold stored plants inoculated with zoospores of Phytophthora cactorum were used in all experiments. The results showed that resistance to P. cactorum vary greatly between cvs, and the most resistant ones were Senga Sengana, Induka, Melody, Glima, and Bogota, while the most susceptible were Tamella, Inga, Evita and Jonsok. The results were compared to those obtained by other authors, and there were clear indications that the genetic background affects the degree of susceptibility to P. cactorum. Many of the most resistant cvs descend from Senga Sengana (e.g. Bounty, Glima, Induka and Melody), and several of the most susceptible cvs have common parentage (e.g. Inga, Tamella, Elsanta and Evita). In a resistance test of the progeny from two separate crosses between a resistant and a susceptible cv. 61 and 65 % of the offspring were intermediately to very susceptible, and 17 and 13 % were resistant at the level of Senga Sengana. Hence, there is a high risk of losing offspring with high levels of resistance if selection for resistance to crown rot is not performed at an early stage in a breeding programme.
Forfattere
Øystein Johnsen Carl Gunnar Fossdal Rüdiger Baumann Jørgen A. Mølmann Ola Gram Dæhlen David Clapham Tore SkrøppaSammendrag
Det er ikke registrert sammendrag