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.
2023
Forfattere
Arne Stensvand Nan-Yi Wang Vinh Hong Le Claudio Dias Da Silva Jr Belachew Asalf Tadesse Chloé Grieu William W. Turechek Natalia A. PeresSammendrag
Powdery mildew, caused by the ascomycete Podosphaera aphanis, is an important disease of strawberry. A slightly modified version of a method using steam thermotherapy to rid diseases and pests from strawberry transplants was tested against strawberry powdery mildew. Experiments took place in Norway and Florida, with potted strawberry plants heavily infected with the fungus. Aerated steam treatments of the plants were carried out as follows: a pre-treatment with steaming at 37 °C for 1 h was followed by 1 h at ambient temperature before plants were exposed to steaming at 40, 42, or 44 °C for 2 or 4 h in Norway and 44 °C for 4 h in Florida. Following steaming, plants from the different treatments and the untreated control were kept apart and protected from outside contamination of powdery mildew by growing them in closed containers with over-pressure. On steamed plants, hyphae of P. aphanis were dead and without any new spore formation after treatments, independent of temperature or exposure time; however, up to 99% of the area infected with powdery mildew prior to treatments contained actively sporulating lesions on non-steamed plants. None of the new leaves formed after steaming had powdery mildew, whereas more than half of the new leaves on non-treated plants were infected by P. aphanis. This investigation clearly indicates that steam thermotherapy can eradicate powdery mildew from strawberry transplants, and this can be achieved at lower temperatures and exposure times than previously reported for other pathogens.
Sammendrag
The aim of this study was to contribute to development of organic fertiliser products based on fish sludge (i.e. feed residues and faeces) from farmed smolt. Four dried fish sludge products, one liquid digestate after anaerobic digestion and one dried digestate were collected at Norwegian smolt hatcheries in 2019 and 2020. Their quality as fertilisers was studied by chemical analyses, two 2-year field experiments with spring cereals and soil incubation combined with a first-order kinetics N release model. Cadmium (Cd) and zinc (Zn) concentrations were below European Union maximum limits for organic fertilisers in all products except one (liquid digestate). Relevant organic pollutants (PCB7, PBDE7, PCDD/F + DL-PCB) were analysed for the first time and detected in all fish sludge products. Nutrient composition was unbalanced, with low nitrogen/phosphorus (N/P) ratio and low potassium (K) content relative to crop requirements. Nitrogen concentration in the dried fish sludge products varied (27–70 g N kg-1 dry matter), even when treated by the same technology but sampled at different locations and/or times. In the dried fish sludge products, N was mainly present as recalcitrant organic N, resulting in lower grain yield than with mineral N fertiliser. Digestate showed equally good N fertilisation effect as mineral N fertiliser, but drying reduced N quality. Soil incubation in combination with modelling is a relatively cheap tool that can give a good indication of N quality in fish sludge products with unknown fertilisation effects. Carbon/N ratio in dried fish sludge can also be used as an indicator of N quality.
Sammendrag
Det mangel på norske økologiske proteinråvarer med aminosyresammensetning som dekker behovet til enmaga dyr. I denne spillelisten gir gårdbruker Thorbjørn Lund praktiske tips om økologisk dyrking av høstraps.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Tatiana Francischinelli Rittl Reidun Pommeresche Anders Johansen Håvard Steinshamn Hugh Riley Anne-Kristin LøesSammendrag
Renewable energy in the form of biogas can be produced by anaerobic digestion (AD) of animal manure. However, there is still a lack of knowledge on the long-term effects of AD-treated manure on soil characteristics and crop productivity, compared with untreated manure. A field experiment was established in a perennial grass-clover ley in 2011 to study the effects on important soil and crop characteristics when the slurry from a herd of organically managed dairy cows is anaerobically digested. While the rate of manure application affected soil concentrations of extractable nutrients and pH, these variables were unaffected by AD. Soil organic matter (SOM) concentrations decreased in all plots and faster on the plots with high intrinsic SOM. The decrease was similar with application of untreated (non-digested) slurry (US) and anaerobically digested slurry (ADS), and it was not affected by application rates. The general decline may be explained by the initial high SOM content, the long-term effect of drainage, and higher temperatures with climatic change. US and ADS gave similar yields of grass-clover ley (2 cuts/year) and green fodder, on average 0.79 and 0.40 kg DM m−2, respectively. Clover yield was similar in manured treatments and the non-fertilized control. With respect to crop yields and chemical soil characteristics, long-term (10 years) effects of AD in an organic dairy cow farming system seem to be minor. The benefits of extracting energy from the slurry did not compromise grassland productivity or soil quality in the long term.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Intensification and specialization of farming systems in Europe and elsewhere has resulted in poor crop rotations, with low plant and animal diversity. This has resulted in more uniform landscapes, soil carbon loss and low efficiency in nutrient cycling, particularly in regions dominated by annual crops. Inclusion of ley in crop rotations is expected to increase soil organic carbon (SOC) stocks, nitrogen availability and improve soil physical properties. The effect of ley-arable rotations versus continuous annual cropping on soil quality, soil organic carbon and soil biology was assessed by summarizing and discussing results from publications from long-term experiments in Norway and Sweden. These studies support the hypotheses that the inclusion of leys in crop rotations promotes soil fertility and carbon sequestration in Northern Europe, supplies nutrients to subsequent crops and improves soil physical properties. However, one or two years of ley in rotations may not be enough for maintaining SOC and good soil structure over time. For keeping the relatively high SOC concentrations occurring at many sites in Northern Europe, the proportion of ley in rotation should be at least 50%.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Ingerd Skow Hofgaard Heidi Udnes Aamot Till Seehusen Marit Almvik Guro Brodal Ruth Dill-Macky Simon Graham EdwardsSammendrag
In Norway, Fusarium diseases and associated mycotoxin contamination in spring oats occasionally cause problems for growers, livestock producers and the food and feed industries. Besides weather factors, such as rainfall and temperature in the critical periods around flowering and before harvest, inoculum production and disease development are influenced by agricultural practices. The occurrence of Fusarium graminearum and DON in oat grain lots do not generally correlate with that of Fusarium langsethiae and HT-2/T-2-toxins. Therefore, to develop a robust disease management strategy, there is a need to reveal the influence of weather and agricultural practice on disease development in oats for both these fungal species. Through various research projects NIBIO researchers have performed field trials to study the effects of straw management, tillage practice, cultivar, and chemical and biological control treatments on the development of Fusarium spp. and mycotoxins in oats. In particular we have investigated whether the amount of straw residues and tillage practice influences the survival of Fusarium spp. in residues, and the subsequent Fusarium spp. infection of the harvested grains. In addition, Fusarium spp. DNA and mycotoxin content (DON and HT-2/T-2) have been analysed in oats from current official cultivar trials. This work has been a collaboration between NIBIO and the Norwegian Agricultural Extension Service. Results will be presented on the Fusarium spp. and mycotoxin contamination of grains harvested from oats grown under various agricultural practices. High incidence of Fusarium avenaceum are often observed in harvested grains as well as straw residues. Fusarium graminearum is also commonly detected. Despite the high concentrations of F. langsethiae DNA and HT-2/T-2 toxins sometimes recorded in oat grain, only low levels of F. langsethiae have been detected in crop residues and air samples. We speculate that the life cycle of F. langsethiae differs from those of F. graminearum and F. avenaceum with regards to survival, inoculum production and dispersal.