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
Forfattere
jihong liu clarkeSammendrag
Dengue viruses (Flavivirus) are mosquito-borne human pathogens with a worldwide prevalence. There are four antigenically-related dengue virus serotypes, DEN-1 to DEN-4, which can cause serious problems of morbidity and mortality. Dengue is emerging rapidly as one of the most important public health problems in countries of the Asia-Pacific region with nearly 1.8 billion people in the region at risk, compared to an estimated total of 2.5 billion globally (WHO 2007). In India, dengue is now re-emerging as one of the most important health problems, with many outbreaks reported in different parts of the country during the past decade. The disease has resulted in widespread social and economic problems, especially among the poor who are the most vulnerable group. The lack of a dengue vaccine and antiviral drug makes it difficult to control and manage the disease. To combat dengue fever under the influence of global warming and climate change, multiple coping strategies including affordable vaccines, vector control, sanctions, law enforcement and public education are essential. This talk will present the development of a tetravalent dengue vaccine using tobacco plants as a green factory, and the social and economic benefits of the plant-production system will be discussed. Other coping strategies such as vector control and improvement of water quality will also be addressed.
Forfattere
Tatsiana Espevig Michelle DaCosta Trygve S. Aamlid Anne Marte Tronsmo Bruce B. Clarke Bingru HuangSammendrag
Cold acclimation plays a decisive role in turfgrass winter survival. This study was performed in collaboration with Rutgers University and University of Massachusetts (USA) to examine changes in carbohydrate levels in crown tissues during the first and second phases of cold acclimation in velvet bentgrass (Agrostis canina L.) and creeping bentgrass (A. stolonifera L.), and their association with freezing tolerance.. Four treatments representing different phases of cold acclimation were compared: (i) nonacclimated plants maintained at 18 °C/12 °C (day/night); (ii) plants acclimated at 2 °C for 2 wk and 250 μmol m-2 s-1 for 12 h photoperiod ; (iii) as treatment (ii) but for 4 wk; and (iv) as treatment (iii) plus additional sub-zero acclimation in the dark at -2 °C for 2 wk. Velvet bentgrass and creeping bentgrass showed no difference in lethal temperatures for 50% of the test population (LT50) as estimated by whole plant survival. Acclimation at 2 °C for 2 and 4 weeks resulted in accumulation of sucrose and fructans, and significantly lowered LT50 as compared with nonacclimated plants. Subzero acclimation resulted in less fructans, no difference in sucrose, and higher concentration of reducing sugars, but LT50 was not lower than after acclimation at 2 °C for 4 weeks.
Sammendrag
Understanding the feedback between terrestrial biosphere processes and meteorological drivers is crucial to ecosystem research as well as management. For example, remote sensing of the activity of vegetation in relation to environmental conditions provides an invaluable basis for investigating the spatiotemporal dynamics and patterns of variability. We investigate the Fraction of Absorbed Photosynthetically Active Radiation (fAPAR) using SeaWiFS satellite observations from 1998 to 2005 and ancillary meteorological variables from the CRU-PIK dataset. To what extent do precipitation and temperature dominate the terrestrial photosynthetic activity on monthly to interannual time scales? A spectral decomposition using Singular System Analysis leads to a global ‘classification’ of the terrestrial biosphere according to prevalent time-scale dependent dynamics of fAPAR and its relation to the meteorology. A complexity analysis and a combined subsignal extraction and dimensionality reduction reveals a series of dominant geographical gradients, separately for different time scales. Here, we differentiate between three time scales: on short time scales (compared to the annual cycle), variations in fAPAR coincide with corresponding precipitation dynamics. At the annual scale, which explains around 50% of the fAPAR variability as a global average, patterns largely resemble the biomes of the world as mapped by biogeographic methods.At longer time scales, spatially coherent patterns emerge which are induced by precipitation and temperature fluctuations combined. However, we can also identify regions where the variability of fAPAR on specific time scales cannot be traced back to climate and is apparently shaped by other geoecological or anthropogenic drivers. http://uregina.ca/prairies/assets/Prairie_Summit_Final_Program.pdf
Forfattere
Aruppillai Suthaparan Sissel Torre Arne Stensvand Maria Herrero Rolf Inge Pettersen David M. Gadoury Hans Ragnar GislerødSammendrag
When rose plants bearing colonies of Podosphaera pannosa were placed in a wind tunnel, the number of conidia trapped was directly proportional to intensity of daylight-balanced (white) light from 5 to 150 mu mol m(-2) s(-1). Illumination of samples using blue (420 to 520 nm) light-emitting diodes (LEDs) increased the number of conidia trapped by a factor of approximately 2.7 over white light but germination of conidia under blue light was reduced by approximately 16.5% compared with conidia germination under white light. The number of conidia trapped under far-red (>685 nm) LEDs was approximately 4.7 times higher than in white light, and 13.3 times higher than under red (575 to 675 nm) LEDs, and germination was not induced compared with white light. When mildewed plants were exposed to cycles of 18 h of white light followed by 6 h of blue, red, far-red light, or darkness, light from the red LEDs reduced the number of conidia trapped by approximately 88% compared with darkness or far-red light. Interrupting the above dark period with 1 h of light from red LEDs also reduced the number of conidia trapped, while a 1-h period of light from far-red following the 1 h of light from red LEDs nullified the suppressive effect of red light. Our results indicate that brief exposure to red light during the dark interval may be as effective as continuous illumination in suppressing powdery mildew in greenhouse rose plant (Rosa x hybrida).
Forfattere
Trygve S. Aamlid Jon SælandSammendrag
The Norwegian Nature Management Act prohibits use of introduced plant material in natural and semi-natural landscapes. The main objectives of the project FJELLFRØ are (1) to collect parent seed material in mountain regions, and (2) to propagate and develop seed production techniques for these species/ecotypes. The project is owned by Telemark Seed Growers Association, supported financially by Innovation Norway and various public agencies / private companies for the period 2007-2010, and organized by Bioforsk. A total of 420 g site-specific seeds of 227 ecotypes belonging to 33 species have been collected in geographically distant mountain regions in 2005, 2007 and 2008. Species of high priority are Festuca ovina, Poa alpina, Phleum alpinum, Avenella flexuosa, Agrostis mertensii, Anthoxanthum odoratum ssp. alpinum. By November 2009, 38 first generation multiplication fields have been established after raising transplants in nurseries. By the same date, 13 commercial second-generation fields have been seeded by farmers organized through Telemark Seed Grower"s Association. Site-specific seed mixtures are expected for sale from 2011 onwards
Forfattere
Trond HofsvangSammendrag
Two Malaise traps were set up at Ås, Southern Norway, during the growing seasons 1992-1997, one trap in an organic grown barley field and one in its boundary. Totally 23 species of Tipulidae (Diptera) were identified, of these eight species belonged to the genus Nephrotoma Meigen, 1803. Of the total specimens collected 93% of the males and 88% of the females belonged to this genus. Comparing the two traps, 80% of the Nephrotoma specimens were recorded in the organic field. It is discussed if larvae of Nephrotoma spp. in Norway can be potential pests in agricultural crops as reported from other countries. To Malaisefeller ble plassert ut i Ås i vekstsesongene 1992-1997, en i en økologisk dyrket byggåker og en i kanten av åkeren. Totalt ble 23 arter av stankelbein (Tipulidae, Diptera) identifisert, 8 av disse tilhørte slekten Nephrotoma. Av det totale antall individer som ble samlet inn, var 93 % av hannene og 88 % av hunnene av slekten Nephrotoma. 80 % av Nephrotoma-individene ble funnet i den fellen som sto ute i byggåkeren. I mange andre land er larver av Nephrotoma-arter skadedyr på mange kulturplanter i jordbruket, og det diskuteres om disse artene kan opptre som skadedyr i Norge.
Sammendrag
The liquid fertilizers (1) Calcinit (Ca NO3)2)+ Superba, (2) Arena Crystal, (3) Flex, (4) Plant Marvel, (5) Sea Power and (6) Sea Power + Superba were evaluated in two greenhouse experiments growing Agrostis stolonifera on columns filled with 30 cm USGA-spec. sand (ignition loss 1.4%, pH (H20) 5.6, CEC 2.7 meq/100 g dry soil) over 10 cm gravel. In expt. 1 the products were compared at weekly rates of 0.1 and 0.2 kg N/100m2 combined with two irrigation levels (1 x ET and 2x ET) during an 8 wk grow-in period; in expt. 2 as maintenance fertilizer to established turf at weekly rates of 0.05 and 0.1 kg N/100m2. Based on weekly determination of visual turfgrass quality and clipping yields, the ranking of fertilizers in the grow-in trial were Sea Power + Superba > Sea Power > Plant Marvel = Flex > Arena Crystal > Calcinit + Superba. Given as maintenance fertilizer, Plant Marvel and Arena Crystal gave higher visual quality and less invasion of moss than Sea Power, the other fertilizers producing results that were not significantly different. The results are discussed in relation to nitrogen form and the content of other nutrients in the various products.
Forfattere
Stine Rosenlund Hansen Thorkild Nielsen Niels Heine KristensenSammendrag
This report is a mapping of the activities within public procurement of organic food for youth in Denmark, with a special focus on school meals. In Denmark, it is voluntary whether local municipalities or schools arrange school meals or not. Until lately this was also the situation for meals in daycare institutions, but in 2008 a new legislation made it mandatory for the municipalities to offer a lunch meal in all daycare institutions, though this is still mainly financed by user charge. This change in legislation received much public attention, and has been heavily debated. School meals in Denmark were first introduced around 1900 as a social project for children in poverty, and have since been undergoing many changes. In the 1930‟s the warm meal was replaced by a cold lunch. During the 1970‟s free meals for malnourished children was gradually replaced by food stalls, selling milk, bread and fruit. Until the beginning of the 2000‟s such food stalls were widely spread, and in the 1980‟s and 1990‟s it was very common that pupils were responsible for running the stalls, receiving the profit for class excursions etc. In recent years a public and political debate about school meals has again aroused, mainly arguing that the food stalls is often offering a very unhealthy selection of food, and also pointing to the fact that many pupils bring unhealthy lunch from home or from nearby shops. Hence the argument that the public should help to ensure a healthy lunch for the pupils is again beginning to manifest, though there is no consensus on how this should be done and to what extent this should be funded by the public. Over time, more and more schools or municipalities choose to establish school meal systems, but these vary extensively in the way they are organized, what kind of food is served, and how they are financed. This report includes an overall mapping of the different ways of organizing school meals and their dissemination. Organic food has also been increasingly debated in relation to public procurement for children and youth, mainly in relation to meals in daycare institutions. Organic food is used in some school meal systems especially in municipalities inspired by Agenda 21, such as the municipalities in the Green Cities cooperation, but also other municipalities such as Esbjerg, Gladsaxe and Roskilde emphasize organic food. Whether the subject of organic food is discussed and implemented depends on the local values, goals, resources and politics. Hence there are municipalities and institutions with no organic food at all, while others have an organic share of more than 90 %. This is particularly in the municipalities situated in the Greater Copenhagen area. The municipalities in the Green cities cooperation have an average share of 59 % organic in all public procurement. The number is even higher when looking exclusively at public procurement for children and youth. These cases are briefly described in the report, along with a short mapping of other municipalities using organic food in meals for daycare institutions or schools. The report was produced in the iPOPY project, “innovative Public Organic food Procurement for Youth”. Similar reports have been produced for the other iPOPY countries; Norway, Finland and Italy.
Sammendrag
The leaf blotch complex is one of the most important yield limiting disease on wheat in Norway. It is caused by three pathogens, Septoria tritici ( Mycosphaerella graminicola), Stagonospora nodorum ( Phaeosphaeria nodorum), and Drechslera tritici-repentis (Pyrenophora tritici-repentis). The symptoms of each of the pathogens are similar and easily confused with leaf senescence, making it difficult to assess the true disease severity and thus hampering breeding for leaf blotch resistance. To reduce unnecessary pesticide use and the risk of pesticide resistance developing in the fungal populations, timing of disease control measures are based on forecasting models. The degree of a leaf blotch epidemic is determined by initial inoculums, precipitation, temperature, time, availability of susceptible hosts and the degree of susceptibility. During the last 20 years, the start of the growing season as marked by a soil temperature of 5C, has advanced by 1-1.5 days per year (Rafoss, 2009), indicating an increase in the length of growing seasons. The trend for warmer and wetter growing seasons is predicted to continue in the future. It is of high relevance to the wheat industry to understand the impact of these changes on leaf blotch diseases in the field to optimize disease forecasting and management. We have collected data on leaf blotch severity in the field and weather conditions at different wheat growing areas in Norway over the last 10 years. Based on this data, we do not see a general increase in disease severity over the last decade. However, the data shows that there are local shifts in maximum disease severity; areas that support high disease severity and areas that support very little. Given the amount of initial inoculum and availability of susceptible hosts are comparable between the different wheat growing areas, the local climate per site becomes the determining factor for the epidemic. We studied the effect of relatively small, local differences in precipitation, temperature, and start of growing season on leaf blotch development in the field. The analysis of local shifts in climatic conditions and their relation to disease development allows us to estimate the effect of the changing climate on leaf blotch disease in the future.
Forfattere
J Pozdisek Britt I.F. Henriksen A Ponizil I Hunady Anne-Kristin LøesSammendrag
Controlled field trials with legume-cereal mixtures and monocultures were conducted on five organic farms in CR, to determine the suitability for feeding ruminants. Mixtures of 60 % peas to 40 % cereals (wheat and barley) were compared with peas, wheat, and barley monocultures. The obtained results are useful to assess how mixtures may be included in animal feed rations. For feeding beef cattle, it is most beneficial to harvest green matter in the BBCH 79 growth phase (green ripeness), which is characterized by a higher protein and energy content and a lower fiber content. Advantageous crop for beef cattle appeared to be the mixture with peas and barley, because the crude protein and NEL contents come the closest to the requirements for a balanced state between breakdown and synthesis in the rumen (CP 130 g kg-1, NEL 5.9 MJ kg-1 DM). The feed on organic farms, which may provide animals with good health, and potential to utilize their genetic capacity for growth and production.