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.
2010
Sammendrag
Bipolaris sorokinana (teleomorph Cochliobolus sativus) is a widespread pathogen of cereals and many grasses. It can infect seeds, roots and leaves, causing seedling blight, common root rot, foot rot and spot blotch. Inoculum of B. sorokiniana may be seed-borne or arise from infected plant debris in the field and from conidia in the soil. Recent years the pathogen has occurred at high frequencies in seed lots of barley in Norway, especially in the cvs Edel and Annabell. A large proportion of the seed lots tested since 2004 were infected and the average infection frequencies were rather high. In order to evaluate the importance of the seed-borne inoculum in barley and to test the effect of seed treatment fungicides against the pathogen, field, greenhouse and laboratory experiments have been carried out with heavily infected barley seed. The infection level was reduced and plant weight, plant height, field emergence and yields were significantly increased by chemical treatment. The best effect was seen with an imazalil+flutriafol compound which increased the yield by approximately 35 % compared to untreated. A healthy untreated seed lot of the same cultivar included in one of the experiments showed approximately the same level of emergence and yield as the best fungicide treatment of a heavily infected seed lot. The investigations demonstrate that the use of healthy seed, or seed treated with an effective fungicide, is important to reduce the yield losses from B. sorokiniana.
Forfattere
Guro BrodalSammendrag
Det er ikke registrert sammendrag
Forfattere
Guro BrodalSammendrag
Det er ikke registrert sammendrag
Forfattere
Guro BrodalSammendrag
Det er ikke registrert sammendrag
Sammendrag
Increasing nitrogen-use efficiency in agriculture decreases N2O emissions. We wanted to investigate whether intensification of animal production by use of imported feed might improve the nitrogen-use efficiency of agriculture. Based on a review of published surveys of dairy farms, we concluded that where production is based on the local feed production, N-use efficiency is very high. Farms that combine grazing with their own hay/silage production for the winter period are highly nitrogen efficient.
Forfattere
Sissel Hansen Marina A. BlekenSammendrag
The sources of N2O in agricultural soil and strategies to reduce emissions are summarised. The main source of N2O in agricultural soil is denitrification. Conditions for N2O emissions are readily available nitrogen (mainly NO3), a partly anaerobic environment, and readily available carbon. The portion of N2O is greatest with low pH. To decrease N2O emissions from agriculture it is important to increase utilisation of applied nitrogen. Improved utilisation of available manure, reduced nitrogen surplus and improved growth conditions such as soil structure, drainage, and pH are important in this. Data from a longterm field trial with different fertilization and soil compaction are presented. The soil was experimentally compacted by two passes with a tractor, wheel by wheel, shortly before fertilization. Gas fluxes at the soil surface were measured by the soil cover method. In the NPK treatment, soil compaction by tractor traffic in this moist soil increased by two- to threefold the observed N2O emissions per kg of dry matter of feed produced. In cattle slurry treatments the effects of soil compaction on N2O emissions were less pronounced. The observed N2O emission per ha and per unit of production were higher with conventional fertilization than with fertilization adapted to organic dairy farming.
Forfattere
Arne Grønlund Sissel HansenSammendrag
The agricultural sector contributes about 9 % of the officially reported GHG emissions in Norway, and about 13 % when the estimated CO2 losses from peat and arable soils are included. N2O, CH4 and CO2 make up comparable amounts of the emissions. N2O emissions are estimated at 2.1 million tonnes (Mt) CO2 equivalents, originating in fertilizers in soil, livestock manure, runoff, N fixation, residual crops, NH3 in precipitation, and mineralisation of organic soils. CH4 emissions are calculated at 2.2 Mt CO2 equivalents, of which 85 % originates in enteric fermentation of ruminants and 15 % in farmyard manure. CO2 emissions are estimated at 2.7 Mt CO2 equivalents, and include degradation of organic soils (1.8 Mt), C loss from mineral arable soils (0.5 Mt) and fossil fuel combustion (0.4 Mt). The estimates for N2O and CO2 from soils are very uncertain.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Trygve S. Aamlid Arne SvalastogSammendrag
De tre såmaskinene Väderstad Rapid, Underhaugs direktesåmaskin og Stokland ble sammenliknet av frøavlere i Telemark ved gjenlegg av grasfrøeng i falskt såbed. Stokland gav best tilslag.
Forfattere
Trygve S. AamlidSammendrag
Et flaskt såbed er et såbed som ikke jordarbeides kort tid før såing. Denne artikkelen gir råd som slike såbed ved etablering av grasfrøeng uten dekkvekst.