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
Forfattere
Arne StensvandSammendrag
Det er ikke registrert sammendrag
Forfattere
Arne StensvandSammendrag
Det er ikke registrert sammendrag
Sammendrag
Denne artikkelen (abstrakt) tar for seg genetisk variasjon mellom isolat av Monilinia-artar i frukt.
Sammendrag
Monilinia laxa, M. fructigena and M. fructicola cause brown rot of stone and pome fruits, which result in considerable economic losses. M. fructigena causes fruit decay in both pome and stone fruit, while M. laxa causes blossom wilt, twig blight, canker and fruit rot on stone fruit. A special form of the fungus, M. laxa f.sp. mali, is found only in apple, where it causes blossom wilt, spur-kill and canker. M. fructicola is a quarantine pathogen in the EU, and it is thus of important to have reliable identification methods and to monitor the population of these fruit pathogens. More than 90 isolates of Monilinia spp. from the main fruit producing districts in Norway was collected. The isolates originated from cherry, plum, apple, apricot and peach. They were identified by growth characteristics in culture according to EPPO standards (EPPO Bull 33: 245-47) and by a multiplex PCR method (Côté (2004) Plant Disease 88:1219-1225). Thus far, the quarantine organism M. fructicola has not been detected in Norway. M. laxa and M. fructigena were isolated from plum, apricot, cherry and apple, however in apple M. fructigena was isolated only from fruits and M. laxa only from infected fruit spurs (generative shoots). In peach only M. laxa was detected. Genetic variation among the isolates is currently being examined using AFLP.
Forfattere
Arne StensvandSammendrag
Raud marg (Phytopphthora fragariae var. fragariae) er ein karanteneskadegjerar som angrip jordbær og nokre andre artar innan rosefamilien.
Forfattere
Arne StensvandSammendrag
Raud rotròte (Phytophthora fragariae var. rubi) er ein karanteneskadegjerar som angrip bringebær og hybridar av bringebær.
Forfattere
Arne StensvandSammendrag
Det er ikke registrert sammendrag
Forfattere
Arne StensvandSammendrag
Det er ikke registrert sammendrag
Forfattere
Arne StensvandSammendrag
Det er ikke registrert sammendrag
Sammendrag
Fine root production, respiration, longevity and mortality are the major processes in carbon dynamics of the forest soils. The objective of the present work was to determine fine root biomass, respiration and root longevity. The study was carried out at a ten year-old stand of planted Norway spruce (Picea abies) (a clearcut, dominated by natural regrowth of Scots pine and birch) and three stands of Norway spruce, approximately 30, 60 and 120 years old, during 2001 and 2002. The stands were located at Nordmoen, a plain of sandy deposits in southeast Norway.Root biomass of both trees and understorey vegetation (0-1, 1-2 and 2-5 mm in diameter) in the humus layer and mineral soil horizons (to depth of 60 cm) was sampled by soil coring. Root respiration was performed in situ, by measuring the CO2 of excavated fine roots by using the CIRAS-I portable gas analyser. For the root turnover study, altogether 60 minirhizotrones were installed and images were processed. Root biomass and necromass (g m-2), specific root length (SRL, m g -1), root length density (RLD, cm cm-3), number of root-tips and mean longevity (y) were estimated.Root biomass was 2-3 times higher in the mineral soil than in the humus horizon. Compared with other stands, root biomass, SRL, RLD and the number of root tips were highest in the 30-year-old stand. At the 10 and 120 year-old stands understorey vegetation roots counted for 70 and 40% of total root biomass, respectively. The amount of necromass at 60 year-old stand was about twice as high (45%) compared to other stands.Root respiration (g C/min./g roots) was significantly lowest at 10-year-old stand. Root respiration among 30, 60 and 120 year-old stands was not significantly different, but it was highest in the 60-year-old stand. The respiration varied seasonally, with high peaks during the summer and lower values during the spring and autumn. Fine root longevity of tree and understorey roots at the 10-year-old stand were 1.2 and 1.4 years, respectively.It is concluded that stand age may influence the dynamics of the fine roots. The complexity of influences will be discussed.