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.
2007
Sammendrag
Produksjonsklare planter er planter med ferdig utviklete blomsteranlegg, som gir avling 2–3 mnd. etter planting. Gartnerhallen vil starte produksjon av slike planter av jordbær og bringebær av en tilfredsstillende kvalitet. For å klare dette må det skaffes ny kunnskap om vekstfysiologien hos jordbær og bringebær, og derigjennom utvikle nye metoder og produksjonssystemer hos Gartnerhallens sju planteprodusenter. Det er derfor etablert et 4-årig brukerstyrt prosjekt i regi av Gartnerhallen, med Bioforsk og UMB som samarbeidspartnere. Her presenteres noen foreløpige resultater for bringebær etter ett forsøksår.
Sammendrag
Floral induction and development requirements of a range of latitudinal and altitudinal Norwegian populations of the wild strawberry Fragaria vesca L. have been studied in controlled environments. Rooted runner plants were exposed to a range of photoperiods and temperatures for 5 weeks for floral induction and then transferred to long day (LD) at 20 degrees C for flower development. A pronounced interaction of temperature and photoperiod was shown in the control of flowering. At 9 degrees C, flowers were initiated in both short day (SD) and LD conditions, at 15 and 18 degrees C in SD only, whereas no initiation took place at 21 degrees C regardless of daylength conditions. The critical photoperiod for SD floral induction was about 16 h and 14 h at 15 and 18 degrees C, respectively, the induction being incomplete at 18 degrees C. The optimal condition for floral induction was SD at 15 degrees C. A minimum of 4 weeks of exposure to such optimal conditions was required. Although the populations varied significantly in their flowering performance, no clinal relationship was present between latitude of origin and critical photoperiod. Flower development of SD-induced plants was only marginally advanced by LD conditions, while inflorescence elongation and runnering were strongly enhanced by LD at this stage. The main shift in these responses took place at photoperiods between 16 and 17 h. Unlike all other populations studied, a high-latitude population from 70 degrees N ('Alta') had an obligatory vernalization requirement. Although flowering and fruiting in its native Subarctic environment and after overwintering in the field in south Norway, this population did not flower in the laboratory in the absence of vernalization, even with 10 or 15 weeks of exposure to SD at 9 degrees C. Flowering performance in the field likewise indicated a vernalization requirement of this high-latitude population.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Anita SønstebySammendrag
Vi har studert den klimatiske reguleringen av blomsterdanningen hos en rekke norske populasjoner av markjordbær. Resultata viser mange likhetstrekk med det som er kjent for hagejordbær med et utpreget samspill av temperatur og daglengde. Markjordbær er således dagnøytrale og danner blomster i både korte og lange dager ved 9 °C, ved 15 °C bare under kortdags-forhold, mens de ikke evner å danne blomster i det hele tatt ved 21 °C uansett daglengdeforhold.
Sammendrag
Perpetual-flowering strawberry cultivars are commonly classified as photoperiodically day-neutral, even though early investigations demonstrated long-day (LD) regulation. An important reason for this inconsistency is that these freely flowering plants are difficult to establish in a true vegetative state, and experiments have therefore, often been started using runner plants with pre-formed inflorescences. In order to circumvent this problem, we have used the perpetual-flowering F1-hybrid `Elan" that is propagated by seed, and is thus not pre-conditioned by its earlier life history. The results demonstrated a marked quantitative LD response across a range of temperatures from 9º - 27ºC. Seedlings were responsive to the LD stimulus at an early stage, and early flowering required LD exposure almost from germination. The critical daylength for the early flowering response was about 15 h at 18ºC. Because of this threshold LD response, it is concluded that regulation of flowering is truly photoperiodic in nature, and not merely an effect of additional light. Flower development was also slightly advanced by LD conditions. Stolon formation was strongly enhanced by short day conditions in combination with high temperature. Thus, not only flowering, but also runnering, was oppositely affected by photoperiod in `Elan" compared with mono-flowering cultivars. The results are discussed in relation to the photoperiodic classification of strawberries.
Sammendrag
Sortar av solbær og rips for økologisk produksjon må ha god resistens mot viktige soppar og skadedyr. Registreringar i sortsforsøk i fleire regionar syner stor variasjon mellom sortane. Bær av solbær og ripa har høgt innhald av helsefremmande innhaldsstoff, men analysar har synt store variasjonar mellom sortane. Registreringar i fleire år vil syna om sortane rangerer likt frå år til år.
Sammendrag
Ved Bioforsk Øst Kise er det forsøksfelt hvor ripssorter blir prøvd ved økologisk dyrking. Artikkelen presenterer de første resultatene fra forsøkene og gir foreløbige vurderinger av seks ripssorter plantet i 2002. Det presenteres avlingstall, verdier for bær- og klasestørrelse samt kartfall og løst tørrstoff.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er kjent at den fysiologisk tilstanden (alder) hos settepotetene kan ha stor betydning for spireegenskaper, vekstkraft, avlingsstørrelse og kvalitet. Likevel har det vært lite fokus på temaet her i landet. Vi gir her en presentasjon av hva fysiologisk alder er, hva den kan bety for potetdyrkeren og hvordan den kan påvirkes.
Sammendrag
Cover crops are included in cropping systems to achieve various ecological benefits. In stockless organic cereal systems, nitrogen is commonly supplied by undersowing a legume shortly after sowing of cereals. Retarded growth of annual weeds is considered as an additional benefit of using cover crops. There is, however, less knowledge on the influence of undersown cover crops on the growth of perennial weeds. This issue was addressed in a field experiment at Ås in southeast Norway. For obtaining an experimental field with uniform distribution of the perennial weed species, root fragments of Cirsium arvense and Sonchus arvensis and rhizomes of Elymus repens, were transplanted by hand in the spring of 2001. A split plot design with 3 replications was initiated in 2002 and continued until the autumn of 2006. Barley undersown with red clover versus barley alone composed the two main plot treatments, except in 2006, in which barley was grown without red clover in the whole field. This was combined with four sub-plot mechanical treatments in the autumn: 1) untreated control; 2) mowing; 3) rotary tilling and 4) shallow ploughing plus harrowing. The autumn treatments were only carried out in 2004 and 2005. Number of weeds was counted at different dates throughout the growing season, and weed biomass was assessed just before harvest. Preliminary results indicate that red clover undersown in barley, compared to barley alone, reduced the biomass of established stands of S. arvensis by 50%, 42% and 13% in 2004, 2005 and 2006 respectively. The effect on E. repens varied from +10% in 2004 to -42% in 2005 and -50% in 2006. There was no suppression on established stands of C. arvense (+10%, 0 % and +70%). Of the autumn mechanical treatments rotary tilling and shallow ploughing most effectively retarded the growth of perennial weeds, especially C. arvense and E. repens. Rotary tilling and shallow ploughing reduced mean weed biomass for 2005 and 2006 of C. arvense by 80% (rotary tilling) and 40% (shallow ploughing), and E. repens by 77% and 89%, respectively. Mowing and shallow ploughing reduced mean weed biomass for 2005 and 2006 of S. arvensis most effectively, with a reduction of 62% for both treatments. Although the results need more attention before detailed recommendations can be given, the study indicates clearly that the effect of different mechanical treatments in the autumn depend on weed species.