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.
2024
Forfattere
Randi Berland FrøsethSammendrag
Det er ikke registrert sammendrag
Forfattere
Stig Strandli GezeliusSammendrag
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Forfattere
Anne Marthe LundbySammendrag
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Sammendrag
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Sammendrag
Successful introduction of the new cultivars requires proper pomological, phenological and as well as technological evaluation. It is particularly important at the harsh Norwegian climate conditions. Investigations were conducted with apple cultivar ‘Eden‘ / ‘Wursixo‘ (WUR 6), with the aim to establish an optimal balance between yield, fruit quality and bearing regularity. Four different crop load levels were tested in 3 consecutive years in the orchard planted 3.5 x 1 m and trained as slender spindle. Lower crop load levels guaranteed good return bloom, a very high share of fruits harvested during the first picking, and larger fruits. Increasing crop load led to less intensive return bloom, smaller fruit sizes and higher share of fruits harvested during the second picking. It was found that ‘Eden‘ is strictly alternating cultivar and precise crop load levels according to the tree age and tree vigour were defined. In order to keep ‘Eden‘ trees in regular bearing mode crop load levels should be maintained at 4.5-5 fruits cm-2 of trunk cross-sectional area (TCSA) in the 3rd and 6-7 fruits in the 4th growing season
Forfattere
Trygve S. Aamlid Sigridur Dalmannsdottir Marit Jørgensen Kristoffer Herland Hellton Akhil Reddy Pashapu Ievina Sturite Mallikarjuna Rao Kovi Helga Amdahl Carl Gunnar Fossdal Odd Arne RognliSammendrag
Timothy ( Phleum pratense L.) is the predominant forage grass species in the northern parts of the Nordic region. Because of the long andharsh winters and a short growing season, most of it with continuous light, the need for locally adapted timothy seed has been recognizedfor more than a century. However, the seed production of timothy in these marginal environments is unpredictable with acceptable seedyield and quality on average only every third year. Thus, a multiplication scheme for the northern cultivars was established with only pre-basic seed produced in the north, and basic and certified seed produced further south to secure enough seed of good quality. In recentdecades this scheme has been more or less abandoned with continous generations produced in the south. Farmers are complaining andare questioning whether the cultivars has changed and lost winter hardiness. We studied freezing and ice-encasement tolerance of generations of the the northern timothy cultivars ‘Engmo’ (old landrace) and ‘Noreng’(synthetic) multiplied for one, two or three generations in Central, Southern and Northern Norway. The trials introduce very largedifferences in mean temperature, growing degree days and photoperiod between place of parental origin and sites of multiplication so theeffects on fitness observed could arise from both selection and and induced epigenetic changes. Large changes (loss) in freezing and ice-encasement tolerance were observed, especially at the southern location in the first generation.The cultivars behaved differently and there were significant interactions. The extreme phenotypic changes observed might be explained bygenetic selection or epigenetic memory of the environmental conditions experienced during seed production, or a combination of the two.We are currently analysing GBS data of all generations and this will be used to test whether genetic shifts has occured during themultiplication in the different environments.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Floral initiation in biennial-fruiting red raspberry is controlled by the interaction of temperature and photoperiod. To determine the threshold temperatures for short day (SD) floral initiation in early- and late-flowering cultivars, we exposed plants of ‘Glen Ample’, ‘Glen Mor’ and ‘Duo’ to 12°, 16° and 20°C in a daylight phytotron under naturally decreasing autumn daylength at Ås, Norway (59°40’N). While none of the cultivars ceased growing or initiated floral primordia at 20°C, ‘Glen Ample’ and ‘Glen Mor’ initiated buds at 12° and 16°C, whereas ‘Duo’ formed flower buds at 12°C only. Surprisingly, however, all plants flowered abundantly in spring after winter chilling in the dark at −1.5 ± 0.5°C for 7 months. We discuss two possible explanations for this unusual and novel flowering response. Fractional induction is well known in raspberry, and we visualise that in SD at 20°C, the SD requirement is fulfilled, while floral induction is still blocked by inappropriate temperature. A vernalisation-like response is alternatively suggested as this can take place at near-freezing temperatures in the dark. A combination of the two mechanisms is also possible and likely. We conclude, however, that the two floral induction processes are fundamentally different and controlled by different physiological mechanisms.
Sammendrag
Mapping individual tree quality parameters from high-density LiDAR point clouds is an important step towards improved forest inventories. We present a novel machine learning-based workflow that uses individual tree point clouds from drone laser scanning to predict wood quality indicators in standing trees. Unlike object reconstruction methods, our approach is based on simple metrics computed on vertical slices that summarize information on point distances, angles, and geometric attributes of the space between and around the points. Our models use these slice metrics as predictors and achieve high accuracy for predicting the diameter of the largest branch per log (DLBs) and stem diameter at different heights (DS) from survey-grade drone laser scans. We show that our models are also robust and accurate when tested on suboptimal versions of the data generated by reductions in the number of points or emulations of suboptimal single-tree segmentation scenarios. Our approach provides a simple, clear, and scalable solution that can be adapted to different situations both for research and more operational mapping.
Forfattere
Elin BlütecherSammendrag
Før i tiden var det vanlig med blomsterrike slåtteenger over store deler av landet, og de fleste gårdsbruk hadde slåtteenger. Over 80 % av disse engene har nå forsvunnet og etablering av blomstereng er derfor et godt tiltak for å øke mangfoldet av insekter og planter i kulturlandskapet. I 2023 fikk NIBIO forespørsel om utarbeiding av en etablerings og skjøtselsplan for et område på Kjelle. Feltarbeid ble gjennomført 28. august av Elin Blütecher. Denne etablerings- og skjøtselsplanen gir restaurerings- og skjøtselsråd for blomstereng på den utvalgte lokaliteten.