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.
2017
Forfattere
Anne-Grete Roer Hjelkrem Heidi Udnes Aamot Guro Brodal Einar Strand Torfinn Torp Ruth Dill-Macky Simon G. Edwards Berit Nordskog Ingerd Skow HofgaardSammendrag
Det er ikke registrert sammendrag
Forfattere
N.P. Havill J. Elkinton J.C. Andersen Snorre Hagen Hannah J. Broadley G.J. Boettner A. CacconeSammendrag
The European winter moth, Operophtera brumata, is a non-native pest in the Northeastern USA causing defoliation of forest trees and crops such as apples and blueberries. This species is known to hybridize with O. bruceata, the Bruce spanworm, a native species across North America, although it is not known if there are hybrid generations beyond F1. To study winter moth population genetics and hybridization with Bruce spanworm, we developed two sets of genetic markers, single nucleotide polymorphisms (SNPs) and microsatellites, using genomic approaches. Both types of markers were validated using samples from the two species and their hybrids. We identified 1216 SNPs and 24 variable microsatellite loci. From them we developed a subset of 95 species-diagnostic SNPs and ten microsatellite loci that could be used for hybrid identification. We further validated the ten microsatellite loci by screening field collected samples of both species and putative hybrids. In addition to confirming the presence of F1 hybrids reported in previous studies, we found evidence for multi-generation asymmetric hybridization, as suggested by the occurrence of hybrid backcrosses with the winter month, but not with the Bruce spanworm. Laboratory crosses between winter moth females and Bruce spanworm males resulted in a higher proportion of viable eggs than the reciprocal cross, supporting this pattern. We discuss the possible roles of population demographics, sex chromosome genetic incompatibility, and bacterial symbionts as causes of this asymmetrical hybridization and the utility of the developed markers for future studies.
Sammendrag
Life cycle assessment (LCA) allows systematic comparisons of environmental performance between different products. The functional unit in LCA for milk production is typically set to 1 kg energy corrected milk. This does not however suffice as definition to allow for comparing different studies. The definition of reference flow can introduce a bias between organic and conventional farming systems. We strongly encourage to include definition of reference flow calculation, choice of algorithm for energy calculation as well as choice of energy content of milk in the communication of any results.
Forfattere
Marek Marian Pierzchala Knut Kvaal Karl Stampfer Bruce TalbotSammendrag
Cable yarding is a semi-mechanized timber harvesting system that relies on human machine interaction where a considerable share of the work is done by forest workers. The system is used in mountain forests around the world. Automation of one or more functions could contribute to increased productivity, reduced physical workloads and improved safety conditions. This paper presents a method for sensor data fusion in order to automatically distinguish work phases using Partial Least Squares Discriminant Analysis (PLS-DA). The Robot Operation System (ROS) is implemented to allow for real-time data processing with a maximum latency of 0.16 s. Global Positioning System (GPS), Inertial Measurement Unit (IMU) and camera integration provided a robust solution for 78% correct process segmentation. These results provide a basis for further development from which there is a possibility of expanding this approach for semi-automation, remote control, and autonomous operation.
Sammendrag
The plant hormone auxin is a vital component for plant reproduction as it regulates the development of both male and female reproductive organs, including ovules and gynoecia. Furthermore, auxin plays important roles in the development and growth of seeds and fruits. Auxin responses can be detected in ovules shortly after fertilization, and it has been suggested that this accumulation is a prerequisite for the developmental reprogramming of the ovules to seeds, and of the gynoecium to a fruit. However, the roles of auxin at the final stages of ovule development, and the sources of auxin leading to the observed responses in ovules after fertilization have remained elusive. Here we have characterized the auxin readout in Arabidopsis ovules, at the pre-anthesis, anthesis and in the immediate post-fertilization stages, using the R2D2 auxin sensor. In addition we have mapped the expression of auxin biosynthesis and conjugation genes, as well as that of auxin transporting proteins, during the same developmental stages. These analyses reveal specific spatiotemporal patterns of the different auxin homeostasis regulators. Auxin biosynthesis genes and auxin transport proteins define a prepatterning of vascular cell identity in the pre-anthesis funiculus. Furthermore, our data suggests that auxin efflux from the ovule is restricted in an anther-dependent manner, presumably to synchronize reproductive organ development and thereby optimizing the chances of successful fertilization. Finally, de novo auxin biosynthesis together with reduced auxin conjugation and transport result in an enhanced auxin readout throughout the sporophytic tissues of the ovules soon after fertilization. Together, our results suggest a sophisticated set of regulatory cascades that allow successful fertilization and the subsequent transition of the female reproductive structures into seeds and fruits.
Forfattere
Mekjell MelandSammendrag
Hjå eple og plomme er det heilt turvande å regulera avlinga for å oppnå jamne avlingar av god kvalitet. I kommersiell dyrking er vanleg dyrkingspraksis å regulera avlinga kjemisk eller med hand under blomstringa eller på kartstadiet. Den kjemiske tynninga vert utført under blomstringa eller på liten kart. Då vert grovtynninga utført. I etterkant vert det justert for hand. Dei siste åra har det i Europa vorte arbeidd med alternative løysingar som er mekanisk tynning med maskin. Prinsippet er eit traktormontert utstyr med roterande trådar som vert køyrt på kvar sida av trerekkja under blomstringa. Ein del blomar vert då slått av slik at ei grovtynning vert gjort. Feltsesongen 2010 vart gjennomført to feltforsøk med utprøving av den tyske maskinen Baum for mekanisk blomstertynning, eit i eple med eplesorten Summerred poda på grunnstamma M9 og eit i plomme med plommesorten Opal poda på grunnstamma St. Julien A. Feltforsøka vart gjennomførde i kommersiell frukthagar nær Nibio Ullensvang........
Forfattere
Lars Sandved DalenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Juliana PerminowSammendrag
Det er ikke registrert sammendrag
Forfattere
Rolf Nestby Sebastien GuérySammendrag
OBJECT: Improved precision fertilization by introducing sensors and remote control to secure fruit yield and reduce nutrient leaching in soil culture. MATERIAL AND METHODS:We broadcasted before bedding and mulching 50 g m–2 of a multi-mineral fertilizer. Beds had two plant rows 20 cm apart, with plant distance of 25 cm. Experimental design was split plot with three replications and three treatments. Treatments: fertigation in large plots, cultivar in small plots and year. RESULTS: Plant development in the establishing year had no benefit of fertigation in addition to fertilizer given before bedding. When the yield is 3 kg m–2 a nutrient solution of 6 g N m–2 gave highest yield, using 4 g m–2 from two weeks before harvest and during harvest. ‘Florence’ and ‘Sonata’ developed well; however, ‘Florence’ had mildew on fruits in the last cropping year. ‘Korona’ presented well the first cropping year, but grew small fruits heavily infested by mildew in the last cropping year. CONCLUSION: Fertilization had effect on fruit yield. It is discussed how a fertilization schedule for the establishment year and cropping years can be adapted to plant development stages. Mildew infestation on fruits was dependent of cultivar and fertilization. Introducing sensors for recording of growth factors and in situ ion-levels of soil water nutrients, proved valuable.