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.
2015
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Seyda Ozkan Søren Østergaard Turid StrømSammendrag
Det er ikke registrert sammendrag
Forfattere
Live Lingaas Nesse Anne Marie Bakke Trine Eggen Kristian Hoel Magne Kaldhusdal Einar Ringø Siamak Pour Yazdankhah Erik-Jan Lock Rolf Erik Olsen Robin Ørnsrud Åshild KrogdahlSammendrag
Det er ikke registrert sammendrag
Sammendrag
Leaf blotch diseases in wheat can cause yield losses above 30 %. The necrotrophic fungus Parastagonospora nodorum is the dominating leaf blotch pathogen in Norwegian spring wheat. It has been well documented at the seedling stage that the pathogen produces necrotrophic effectors (NEs) which induces cell death in plants carrying susceptibility genes (Snn), allowing the necrotroph to enter. However, the role of these interactions under field conditions is less researched. In this study, we conducted field experiments with bi-parental and association mapping populations of spring wheat, to investigate the role of NE/Snn in adult plant resistance. The populations have been genotyped with the Illumina 90 K SNP chip, P. nodorum has high genetic diversity and both sexual and asexual reproduction, but the actual adaptation of the pathogen population to cultivars with different levels of resistance is not well studied. We are screening a collection of Norwegian isolates from known host sources to look for differences in NE-frequencies and haplotype distribution. The mapping populations are also inoculated and infiltrated with culture filtrates from single isolates on the seedling stage. Isolates involved in novel interactions will be deepsequenced in order to look for candidate effector genes. Potential effector proteins will be purified by LPC and HPLC to confirm their role in disease development.
Sammendrag
Leaf blotch diseases in wheat can cause yield losses above 30 %. The necrotrophic fungus Parastagonospora nodorum is the dominating leaf blotch pathogen in Norwegian spring wheat. It has been well documented at the seedling stage that the pathogen produces necrotrophic effectors (NEs) which induces cell death in plants carrying susceptibility genes (Snn), allowing the necrotroph to enter. However, the role of these interactions under field conditions is less researched. In this study, we conducted field experiments with bi-parental and association mapping populations of spring wheat, to investigate the role of NE/Snn in adult plant resistance. The populations have been genotyped with the Illumina 90 K SNP chip, P. nodorum has high genetic diversity and both sexual and asexual reproduction, but the actual adaptation of the pathogen population to cultivars with different levels of resistance is not well studied. We are screening a collection of Norwegian isolates from known host sources to look for differences in NE-frequencies and haplotype distribution. The mapping populations are also inoculated and infiltrated with culture filtrates from single isolates on the seedling stage. Isolates involved in novel interactions will be deepsequenced in order to look for candidate effector genes. Potential effector proteins will be purified by LPC and HPLC to confirm their role in disease development.
Sammendrag
Mold growth on the surface of wooden façades is usuall y dealt with by using surface treatment such as paint with fungicides. However, new developments in architecture ar e m oving towards less use of coating, and more use of untreated wooden clad dings. Mould growth is well understood and described, and several m odels for predicting mould growth on building materials exist. It is commonly k nown that mould growth is directly controlled by the cli mate which the w ood is exposed to. Several authors identify humidity, temperature and time as the main drivers of mould growth. However, most of the cu rrent g rowth models developed are based on lab oratory measurements at stable climatic conditions. Consequently, these models are less suitable for prediction of mould growth on exterior surfaces exposed to rapidly changing weather conditions . T his paper analyses the effect of variations of meteorological data on the mould growth on wooden clad dings. An experimental setup of wood samples was exposed to outdoor conditions and h ourly weather conditions as well as t he mould growth at different intervals were measured. The measurements were supplied with 1- D Heat And Moisture (HAM) simulations to provide a more accurate estimate of the conditions on the surface of th e sa mples. The purpose of the analysis was to evaluate if an existing mould growth model might be applicable also for predicting outdoor mould growth. Several profiles of temperature and moisture were co ntinuously monitored on different locations of an eight - story building made from Cross Laminated Timber (CLT). The results from the an alysis of the samples of wood cladding were used to model the mould growth on different l ocations of the building. Also the drying effect of wind around the building was studied. The study shows that there is large variatio n of potential mould growth on the façade of the building.
Forfattere
Anna Helena Petersen Paula Utigard Sandvik Tore Einar SveistrupSammendrag
Det er ikke registrert sammendrag
Sammendrag
There have been intense discussions about reducing fossil energy dependence for many years, indeed there is a vision to have a carbon-neutral energy system in Scandinavia by the year 2050. One way to address this ambition is to increase the use of woody biomass. This places a focus on forest tree breeding, since it is considered to be one of the most effective and environmentally friendly options to increase sustainable biomass production in our forests. In this report we have summarised information about forest tree breeding in Denmark, Finland, Norway and Sweden, covering historic, current and future activities. It includes estimates of realised genetic gain in volume and dry matter production on a regional basis for regeneration materials of different improvement levels, which are available today and will be available in the year 2050. Genetic gains in economic terms are also discussed, and basic breeding and mass propagation principles are described. The report includes the most relevant commercial forest tree species in Scandinavia: Scots pine, Norway spruce, Sitka spruce, Douglas fir, grand fir, birch, poplars, alder, oak and beech. Intensive and long-term breeding is carried out continuously in Sweden and Finland for Scots pine, Norway spruce and to some extent birch, while other species are worked with intermittently. In Norway the interest in breeding has, after a break of some years, now resumed, resulting in the initiation of a new breeding cycle for Norway spruce. The present resources put into breeding in Denmark are small, due to a major change in silvicultural management towards natural regeneration in the State Forests. However, as in all the other Scandinavian countries, there is great potential to increase growth through breeding. Seed from seed orchards is, and will within coming decades, be the main way to supply the forestry with genetically improved plant material. The extra gain in yield that is obtained by using material from existing seed orchards varies among species, but in general it is, on average, 10–15% when compared to local unimproved material. In 2050 it is estimated that this gain will be 20–25% for many species, which is a substantial increase in productivity. The time elapsed from establishment of a seed orchard to the first seed harvest for many species is quite long (10–20 years) and delays the realisation of the genetic improvement efforts. An alternative is to use plants obtained from the vegetative propagation of genetically well-performing seed sources or individuals, which makes it possible to capture the progress from breeding immediately. Utilisation of clones is also a way to reduce the consequences of limited amounts of seed from seed orchards, which for instance, is the case for Norway spruce in southern Sweden. For Norway spruce, using clonal material can immediately deliver a gain of around 25–35% in yield, and it is estimated that by 2050 this figure will have increased to 40%. It should be noted, however, that the use of clonal material may be limited by forest regulations. Future climate change will probably alter the growing conditions in Scandinavia in a way that makes forestry with high productivity exotic species such as Douglas fir, grand fir, Sitka spruce and poplars more attractive. Using several species, instead of the few traditional ones, is a way to spread the risk of an unknown future. In Denmark, several exotic species have been an integrated part of forestry for more than 100 years. Limited breeding work has been performed for these species and the gain in yield is, for instance, estimated to amount to 40% for existing seed orchard material of Sitka spruce compared to unimproved material.
Forfattere
Mark Hughes Callum Aidan Stephen Hill Alexander PfriemSammendrag
The mechanical properties of thermally modified wood are discussed with regard to toughness. The molecular origins of the mechanical properties and, in particular, the role of the hemicelluloses are considered. The important role of water and its interaction with the cell wall components is also examined. The properties are discussed from the point of view of composite theory, with the three main macromolecular components acting as reinforcement, matrix and interfacial coupling agent. The important role that hemicelluloses play as a coupling agent between the cellulosic microfibril reinforcement and the lignin-rich matrix is highlighted. Destruction of the hemicelluloses during the thermal modification process has a profound effect upon the mechanical behaviour.
Forfattere
Magdalena Broda Bartłomiej Mazela Katarzyna Królikowska-Pataraja Callum Aidan Stephen HillSammendrag
The archaeological wooden oak piles of medieval "Poznan" bridge, situated at the bottom of Lednica Lake in Greater Poland, are a valuable relic of the beginnings of the Polish country. The assessment of the state of wood preservation will allow to propose the most appropriate conservation agents and methods in order to save this cultural heritage. The aim of the study was to evaluate the degree of degradation of waterlogged piles by using traditional and non-destructive testing methods and to estimate the usefulness of non-destructive FT-IR and computed tomography techniques in such an assessment. The applied traditional, destructive methods, like chemical and physical, as well as non-destructive ones, like X-ray CT or FT-IR, showed that the archaeological oak wood elements are quite well preserved, especially their heartwood part. The obtained results clearly confirm that the modern X-ray CT measurement and FT-IR analysis can be very useful in archaeological wood research, giving a good insight into wood structure.