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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.

2011

Sammendrag

ClimaRice is a research project on climate change adaptation and rice production, livelihoods and food security in Tamil Nadu and Andhra Pradesh, India (http://www.bioforsk.no/climarice/). One objective of ClimaRice is to explore the potential for use of mobile technologies in the context of climate change adaptation in agriculture. Modern mobile telephone technology is a key component of the ongoing communication revolution which in turn has great potentials for social change and development. Farmers deal with day to day variability in weather conditions. This adaptation of farmers, e.g. towards weather forecasts, could be viewed as a short term analogy to the long term adaptations to climate change. Improved access to weather forecasts and other relevant warnings of weather driven events relevant to rice cropping such as plant pest and disease forecasting is another priority of ClimaRice. Most farmers are already using mobile phones for various day to day needs, but the technology has a wider potential in supporting their main profession; agriculture. Linking mobile technology with adaptation measures developed in ClimaRice projects could form new and powerful measures to meet the threats from climate change and provide support in sustaining rice production. As a first step ClimaRice researchers are using mobile technology to collect field research data when taking observations and conducting survey interviews in the field. The major advantages of a work flow based on mobile field data collection is that the sampled data can be directly posted from the field and stored in an online central database, reducing the risk of data loss. The integrated support for determining geographical position (GPS) automates the procedure of associating such information with the observations taken. The location information can also be used for quality control, e.g. to check whether the observations are taken in accordance with a predefined sampling plan. In addition to improving quality and efficiency of field data collection, valuable experience about performance of mobile phones under tropical field conditions is expected. Important aspects that will be considered are battery capacity under operational data collection, network coverage, screen visibility etc.  

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The trans-border brown bear population of Pasvik-Inari-Pechenga (Norway-Finland-Russia) has been monitored using genetic analyses of feces collection since 2005. In addition in 2007, hair traps were systematically placed out in the area to collect hairs for genetic analysis, to more precisely determine the minimum numbers of bears. In 2011, we repeated this hair trap study, using the exact same methodology as in 2007, to make a direct comparison of the results from the two years. Brown bear DNA was detected in 68 of 88 hair samples (77%) obtained from hair traps in 2011 and for 56 of these samples, a complete DNA profile could be determined. We identified 20 different bears in 2011, 12 females and 8 males. Only one bear was found in more than one country (Norway and Russia). We detected 11 bears in Norway, 7 bears in Finland and 3 bears in Russia in 2011. Four of these 20 bears were previously unknown, all four from Finland. A comparison of the results from 2007 and 2011 showed that we detected fewer bears in hair traps in 2011 (20 bears) than in 2007 (24 bears), but this modest difference may be coincidental. However, we observed a large drop in the yield of hair samples in the traps in 2011 compared to 2007 (88 versus 196 samples). This observation may be suggestive of some reduced activity of bears within the study area in 2011. In addition, only five (21%) of the bears caught in hair traps in 2007 were recaptured in 2011, which indicates a substantial turnover of individuals and may indicate that more frequent hair trapping monitoring would be beneficial to reliably track changes in the population. Additional samples (mainly scats) collected opportunistically in the field within the Russian and Finnish parts of the study area in 2011 detected four male bears in the Finnish part that had not been detected by hair traps. No additional samples from Norway were included to this study and any comparisons between the hair-trapping and opportunistic sampling at this point remains difficult. However, the results indicate that both methods combined are currently the most feasible methods to monitor brown bear numbers in an area.

Sammendrag

The use of Chinese cabbage as a trap crop where insect pathogenic fungi may prolifereate has been tested in a series of push-pull strategy experiments both in the laboratory and in the field. The pest species studied are the cabbage- and turnip root fly (Delia radicum and D. floralis). In a dual choice laboratory experiment, both healthy and Entomophthora muscae inoculated D. floralis were tested for choice of plant for oviposition. The choices were 1) Broccoli against Broccoli 2) Chinese cabbage against Broccoli 3) Broccoli against Broccoli under sown with clover 4) Chinese cabbage against Broccoli under sown with clover. In a semi-field pilot study with Broccoli and Chinese cabbage the choice between main - and trap crop for healthy and inoculated flies, as well as fungal transmission between flies over time, was studied. A pilot field study has also been performed to investigate the overall effect of using Chinese cabbage as a trap crop as well as studying the spatial distribution of Delia eggs in a cabbage field. The results from the dual choice experiment and both pilot studies indicates that using Chinese cabbage as a trap crop is a promising strategy for the management of D. radicum and D. floralis, both as a oviposition attractant and as a trap crop where insect pathogenic fungi may proliferate and kill the adult flies.  

Sammendrag

In 1955 the potato cyst nematode was recorded for the first time in Agder. This detection produced the initial legislation of PCN control, and was implemented based on the statutory regulation of 1916. Since 1956 PCN was given quarantine status in infested agricultural land and home gardens. Official controls of certified seed potatoes started in 1939. Each year about 3000 soil samples are analyzed for PCN to clear areas for certified seed potato production.  These areas are so far free of PCN. The total acreage with seed potatoes in 2009 was 813.7 Ha. Extensive surveys started in 1955; and were carried uninterrupted until the end of the 1990ties. These surveys included producing potato agricultural land and home gardens. In 2009 a new national survey program for the principal potato districts has started, the surveys is aimed to update the PCN occurrence. The surveys will continue during the subsequently years until all major potato areas will be cover.  Statutory regulations for PCN from 1956-2010 to Support to Norwegian Food Safety Authority The regulations have without doubt contributed in preventing PCN infestations in the seed potato areas, and probably also prevented further spreading of wPCN and virulent yPCN as each the find has been placed under quarantine. Permanent grass as a statutory regulation in home garden plots may have contributed to reduce the spread of wPCN to commercial fields. The regulations have most probably made possible the early reduction in use of chemical fumigants, organophosphates or carbamate nematicides.  These chemicals have not been used since the early 1970s. The domestic production of seed potato has been kept free of PCN by frequent inspections and analyses for more than 50 years. The fact that farmers are not allowed to import seed potatoes adds to the level of security. New project Studies on the biology of potato cyst nematodes (Globodera spp.) under Nordic conditions for improving management and regulation in Norway. To increase the scientific basis for amending the management system for PCN, Globodera spp under Nordic conditions.

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An African Green Revolution cannot succeed without a secured supply of mineral fertilizers. This is particularly true of phosphorus, one of the key essential macronutrients. In most tropical soils, P is one of the main limiting plant nutrients and its deficiency is a major constraint for better crop production. This is mainly attributable to (i) the low total P content in soil, (ii) the relative unavailability of inherent soil P for plant uptake, and lastly (iii) the relative speed at which applied soluble sources of P such as inorganic P fertilizers and manures become fixed or changed to unavailable forms. It is clear that mining P minerals and spreading P fertilizers over the landscape is not sustainable in the long run. Cultural practices which can secure P sources and which conserve P should be made use of. Some of the measures necessary to adequately address the P problem can be listed as follows: nutrient cycling through the recycling of crop residues, green manures, animal manures, domestic and industrial wastes; the integration into the cropping system of Pmobilizing plant species which show the ability to improve P uptake even from less labile P forms and store P in the aboveground biomass even in excess of their needs; and biological means making use of mycorrhiza and other soil fauna to help extract fixed P from deep soils under low pH conditions.

Sammendrag

This paper provides an overview of the Norwegian biomass resources for bioenergy use, bioenergy market and frame conditions through a comparison with Denmark, Finland and Sweden, which have a leading role in bioenergy production in the European Union. Although the contribution of renewable energy in Norway is among the highest in Europe (58%), mainly due to hydroelectricity, bioenergy has a low contribution to Norwegian energy supply (6%). As the experience from the other EU Member States showed, long-term, stable policies and relatively strong incentives are needed to initiate and build up a bioenergy market. In Norway, there is still a significant available potential for increasing the bioenergy contribution to the energy supply. The abundance and relatively low prices of energy (i.e. fossil fuels,  electricity), in connection with the need of high investment costs, did not favour so far bioenergy production. Additional forest biomass may be mobilised in Norwayby more intensive management of currently exploited forests. However, there are several limitations related to topography, accessibility and economics. The biomass resources and the full range of technologies available for heat or electricity generation both at small and large scale that can provide good opportunities for increased bioenergy production. The experience gained in Denmark, Finlandand Sweden may be relevant for Norway, as well as for other EU Member States, where there is a deficit of mobilization of biomass resources and insufficient industrial integration of bioenergy with other forest-based sectors.

Sammendrag

Different procedures for managing stubble and regrowth in meadow fescue (Festuca pratensis Huds.) seed crops were examined in two experimental series in southeast Norway. The first series investigated cutting and removal of stubble shortly after seed harvest in late July/early August, combined with cutting of regrowth (forage harvest) in September or October or burning of the wilted aftermath in early spring. Except for one crop with more than 30-cm stubble, stubble removal shortly after seed harvest did not improve seed yield in the following year. On average for plots with and without stubble removal in seven seed crops, forage harvest on 5 September or 1 October reduced seed yield by 9 and 12%, respectively. The reductions were due to smaller inflorescences, probably reflecting lower carbohydrates reserves. In most trials, the highest seed yield, on average 9% above that of the uncut and unburned control, was found after burning in spring. The second experimental series investigated flail-chopping in spring as an alternative to burning, and the effect of delaying either of the two treatments. On average for four trials, burning and flail-chopping before growth initiation increased seed yield by, in turn, 20 and 12% compared with the untreated control. A two-to-three-week delay in fail-chopping had no negative impact, but a two-week delay in burning reduced seed yield back to the uncut/unburned control level. Based on these trials, growers are recommended to burn meadow fescue seed crops in early spring rather than removing stubble and regrowth in autumn. If burning in early spring is not possible, flail-chopping is recommended within two weeks after growth initiation.

Sammendrag

 Winter injury of temperate grasses used for turf is a significant problem in northern climatic regions. Field trials at two locations in Norway previously demonstrated differences in winter survival between two Agrostis species, velvet bentgrass (Agrostis canina L.) and creeping bentgrass (Agrostis stoloniferaL.). The freezing tolerance is an important component of winter hardiness of turfgrasses and it was studied under controlled environments. We also determined the crown carbohydrate and protein changes at different stages of cold acclimation of velvet bentgrass and creeping bentgrass and assessed their relationship to freezing tolerance. Similar freezing tolerance in velvet bentgrass and creeping bentgrass was associated with similar levels of sucrose in crown tissue of acclimated plants. Significantly higher crown fructan content in creeping bentgrass than in velvet bentgrass had no significantimpact on LT50 and suggested negligible direct contribution of fructans to freezing tolerance. Increased freezing tolerance in response to cold acclimation was associated with enhanced amino acid synthesis, since serine hydroxymethyltrasfernse and methionine synthase were up-regulated by acclimation. The first acclimation stage caused more changes in the crown protein composition than subzero cclimation. 

Sammendrag

The objective was to investigate whether the concentration, composition and rumen in sacco degradability of the neutral detergent fibre fraction in forages are affected by preservation method. A mixed crop of timothy, meadow fescue and red clover was preserved as hay, direct-cut or wilted silage at succeeding developmental stages. Pure crops of timothy and perennial ryegrass were preserved as direct-cut silage only. In both grasses and mixed crops, and especially at early phenological stages, restricted silage fermentation after addition of formic acid caused considerable degradation of ash-free neutral detergent fibre (aNDFom). In direct-cut mixed and pure grass silages, the aNDFom content was 50 and 40 g/kg DM lower than in the respective fresh crops. For grasses, the indigestible proportion of aNDFom was higher in silages than in the corresponding herbage. There were few differences in fibre characteristics between restrictedly fermented silages and silages that were extensively fermented due to inoculation with lactic acid bacteria. Irrespective of crop developmental stage, wilting for silage production and drying to hay led to a considerable increase in the aNDFom content, amounting to nearly 90 g/kg DM for the grass-clover crop. The increase was possibly caused by formation of N compounds which were recovered in the degradable fraction of aNDFom and of indegradable products. Ensiling reversed effects of wilting on aNDFom. Results indicate that predictions of feed intake or structural value of forages based on total content and degradability of aNDFom may be biased by changes in the fibre fraction during preservation.

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Abstract Introductions of the pine wood nematode (PWN), which causes Pine Wilt Disease (PWD), have devastating effects on pine forests in regions with susceptible host trees under suitable climate conditions. Norwegian authorities have proposed a contingency plan if PWN is detected in Norway. We compare the costs of implementing this plan with the costs of further spread and damage of PWN under two climate change scenarios: present and the most likely future climate. With the present climate, PWD will not occur in Norway. Under climatic change, the cost of PWD damage is approximately 0.078- 0.157 million NOK (0.01-0.02 million Euros) estimated as net present value with 2 and 4% p.a. discount rate. In contrast, the corresponding costs of implementing the suggested contingency plan will be 1.7-2.2 billion NOK (0.2-0.25 billion Euros). These costs are caused by reduced income from industrial timber production and the costs of the eradication measures. Costs related to reduced recreation or biodiversity are expected to be very high, but are not included in the above estimates. Many of the factors in the analysis are burdened with high uncertainty, but sensitivity analyses indicate that the results are rather robust even for drastic changes in assumptions. The results suggest that there is a need to revise the current PWN contingency plan in Norway. Keywords: Bioeconomics, boreal forest damage, Bursaphelenchus xylophilus, climate change, impact assessment, stochastic modelling.