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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.

2012

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Sammendrag

For å øke fruktbarheten hos norsk sau ble finsk landrase importert og utprøvd i kryssing med norske raser fra 1967-76. Det er gitt et sammendrag av forsøksresultata og presentert beregninger fra den første tida finsk sau ble kryssa inn i praktisk sauehold. Nors kvit sau (NKS) er ikke tilført finsk blod etter 1992. I rapporten er det vist at 2000-årgangen av avkomsgranska NKS-værer i middel hadde ca. 5,8 % og 2009-årgangen ca. 4,5 % finsk blod. Regresjonsanalyser for avlsverdier (indekser) for ulike egenskaper på andelen finsk blod i værene, viser at finneinnslaget gir økt slaktevekt hos lam, mer fett på slakta (som er uønsket), dårligere melkeevne hos søyene og økt lammetall. Med unntak av dårligere melkeevne, er dette i tråd med de tidligere forsøksresultatene. Mulige årsaker til lavere melkeevne og virkning av finsk innslag på andre egenskaper som kroppsvekt, fôrforbruk m.fl. er drøfta. Finneinnslaget på ca. 4,5 % i NKS i dag gir en økning i lammetallet på ca. 0,10 lam pr. fødsel. Med det høge lammetallet som er oppnådd gjennom avlsarbeidet de siste 10-12 åra er det ikke aktuelt å tilføre NKS nytt finsk blod.

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This Technical brief is a short summary of the results obtained from the field trials conducted at Agro Climate Research Centre, Tamil Nadu Agricultural University, India to understand the Pest dynamics at elevated temperature. Among the major food crops, rice (Oryza sativa L.) forms the stable food for more than half of the world’s population. Among various constrains in rice production, losses due to pest is a major concern. Climate change resulting in increased temperature could impact crop insect pest populations in several complex ways. Although some climate change temperature effects might tend to depress insect populations, most researchers seem to agree that warmer temperatures in temperate climates will result in more types and higher populations of insects. Hence, it is important to understand the population growth of the important insect pests such as yellow stem borer (Scirpophaga incertulas) and brown planthopper (Nilaparvata lugens) of rice. The results revealed that there was an inverse correlation between temperature and total life span, developmental time and also fecundity. However there was a positive correlation between temperature and net reproductive rate and development rate.

Sammendrag

I underkant av 14 % av registrerte bønder i Norge er kvinner, til tross for at økt andel kvinner i landbruket lenge har vært et satsingsområde både for landbrukets organisasjoner og myndighetene. Bioforsk Økologisk har på oppdrag fra Møre og Romsdal Bondelag gjennomført 12 dybdeintervju av kvinner med tilknytning til husdyrproduksjon i Møre og Romsdal. Formålet med oppdraget var å få innblikk i tanker og erfaringer rundt det å være kvinnelig bonde. Hvilke faktorer spiller inn på valget av yrke, og hva tenker de kan være årsaker til den lave kvinneandelen i norsk landbruk.

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Farmers attempt to develop a different environment for rice under System of Rice Intensification (SRI) method by which the rice plants can exhibit their full potential. Major principles of SRI includes perfect land levelling, lower seed rate, transplanting young seedlings of 12 days old, single seedling / hill with wider spacing (25 x 25 cm), careful water management (applying a minimum of water during vegetative growth and at later stages maintaining only one inch water) and weed management using cono weeder thrice in the vegetative stage. Researchers and farmers’ experience in the Cauvery basin in Tamil Nadu from ClimaRice have shown that yields of rice could be increased considerably (18–27%) with reduced water consumption (22- 25%) and less expenditure, just by following SRI method of cultivation. Thus it is beneficial for small and marginal farmers under changing climatic conditions.

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Cover crops are included in cropping systems in order to achieve various ecological benefits. In stockless organic cereal systems in Scandinavia, nitrogen is commonly supplied by undersowing a legume shortly after sowing. Retarding the growth of annual weeds is considered an additional benefit of using cover crops. However, studies on the influence of undersown cover crops on the growth of perennial weeds are lacking. In this paper we present data from a four- year field experiment on the growth of Cirsium arvense (L.) Scop., Sonchus arvensis L. and Elymus repens (L.) Gould., in cereals with and without undersown red clover (Trifolium pratense L.), combined with contrasting stubble treatments after harvest. Clover did not significantly reduce the growth of any of the weed species. Regression analyses showed, however, that the growth of C. arvense and S. arvensis increased with increasing clover biomass at low densities of clover, whereas at higher densities it decreased with increasing biomass of clover. Amongst the stubble treatments, shallow ploughing followed by harrowing gave the best control of all weed species. The effect was most pronounced on E. repens, and least on S. arvensis, for whichneither the number nor the weed biomass were significantly different from the untreated control. Rotary tilling gave a similar effect, but again less pronounced on S. arvensis. Mowing suppressed E. repens to some degree, tended to suppress S. arvensis (n.s.) but had no effect on C. arvense. Thegrowth and survival of seed-propagated plants of the same species were studied in a one-year field experiment and in a greenhouse experiment, the latter only including the species S. arvensis andC. arvense. The use of a cover crop reduced the number of leaves per plant in S. arvensis both in the field and in the greenhouse. The same effect was found for C. arvense, but only in the greenhouse experiment. In the latter, above-ground biomass of the cover crop explained 67 % of the variation intotal biomass of S. arvensis and 47 % of that for C. arvense. From a practical point of view, the study has shown that undersown red clover has only marginal effects on perennial weeds, in contrast to various stubble treatments which influence strongly on weed growth. In general, soil tillagesuppresses perennial weeds best, but mowing may be a more environmentally friendly alternative for some weed species, such as. E. repens.      

Sammendrag

Pest and disease management in organic greenhouse production in Norway Anette Sundbye1, Nina Svae Johansen2, Arne Stensvand3 1, 2, 3 Norwegian Institute for Agricultural and Environmental Research (Bioforsk) - Plant Health and Plant Protection, Email1: anette.sundbye@bioforsk.no Development of organic farming and marketing of organic products is a political priority in Norway, and the major goal is that 15% of the food production and consumption in year 2020 should be organic. This also relates to vegetables in greenhouses. The demand for organic vegetables is increasing and the consumers are increasingly more conscious of how their food is produced. Norwegian growers who choose to convert to organic cultivation have major challenges when it comes to marketing and keeping a stable production. However, guidance by the Norwegian agricultural extension service on organic production of cucumber has been successful (project “Organic cultivation of greenhouse vegetables and herbs” 2010-2012). Also growers of tomatoes, lettuce and herbs are in good progress in converting to organic production. According to current Norwegian regulations, the organic greenhouse production should mainly be based on natural light. The need for and use of artificial light should be documented and can only be used in certain periods of the cultivation time. The main goal of the project “Environmentally friendly development of Norwegian greenhouse industry (2009-2012)” is to reduce energy consumption in plant production. This is practiced by maximizing the utilization of natural radiation and manipulating the light with different greenhouse covering, shading materials and LED based lamps with specific wavelength spectrum. The effect of light quality on powdery mildew and pests is also studied. Experiments have shown that illumination with red or UV-B light some minutes a day can reduce powdery mildew significantly. Blue sticky traps equipped with low intensity LEDs have the potential to increase thrips catches on sticky traps, and lamps with repellent wavelengths may be used to confuse whiteflies in their host finding. Only a limited number of biological control agents (BCA) are currently registered in Norway. On the international market, a wide range of commercially products of BCA is available. Access to these products would benefit the Norwegian organic production. In order to increase the availability and use of BCA in Norway, two projects have been funded by the Ministry of Food and Agriculture. In the new project “Increasing the use of biological control agents of plant pests” (2012) bottlenecks will be identified and solution will be proposed to promote the registration and increase the use of BCA in Norway. The other project “Extension in greenhouse biological control” (2006-2012) has increased the implementation of biological control and IPM in Norwegian commercial greenhouses.

Sammendrag

Background to the research and aims. Sunflower downy mildew exhibit mixed asexual and sexual reproduction. Rare events of recombination can have a drastic effect on the reshuffling of genetic material and result in the emergence of new virulence combinations. Overview of the methods. In this study, we have used a molecular epidemiology approach to identify population sources, investigate the mating system and track pathogen movement at the field scale. Using a hierarchical sampling design, we have collected 250 P. halstedii isolates from 20 geo-referenced sites in an infected sunflower field located in Southern France. These samples were genetically characterized using 12 single nucleotide polymorphisms markers (SNP) and one microsatellite locus(Giresse et al. 2007) and, for a subset of 60 samples, the virulence profile was determined. Key results. Characterization of virulence profiles revealed the presence of 8 races within the field (100, 300, 304, 307, 703, 704, 707, 714), race 304 being predominant among the samples tested. Race were randomly distributed within the field. Among the 250 isolates that were genotyped, there were 109 different multilocus genotypes (MLG), of which four were highly represented. The significant deficit in heterozygotes observed confirmed that P. halstedii is a highly selfing species (Delmotte et al. 2008). Bayesian clustering analyses revealed that isolates belonged to two genetically differentiated groups (FST> 0.2) that were correlated with race. A low level of genetic differentiation (FST = 0.06) was observed among the 20 sites that were constituted of a mixture of samples from the two groups. Theestimation of gene flow using hierarchical FST and spatial autocorrelation analysis bring evidence a lack of spatial genetic structure that likely result from field plowing. Finally, the estimation of gene flow atvarious scales using hierarchical FST and spatial autocorrelation analysis bring evidence for race emergence through genetic recombination between differentiated genetic genotypes. Main conclusions. This study brings evidence for an absence of spatial genetic structure of P. halstedii population, that could result from field plowing. It also reveals that genetically and phenotypically (virulence) differentiated isolates of P. hasltedii do coexist at a very fine spatial scale. The coexistence of genetically and phenotypically differentiated isolates of P. hasltedii may allow the emergence of new races through recombination. Nature of the contribution to current knowledge. This study has allowed to identify and delineate pathogen populations at the field scale. By bringing new insights in to the evolutionary mechanisms responsible for the emergence of races, these results will help identifying management units for sunflower protection strategies. Keywords. Plasmopara halstedii, race, pathotype, virulence evolution, population genetics

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Sammendrag

Adapting to changing climate is essential for individuals and communities to sustain their livelihoods. Improving adaptive capacity at various levels is essential, and this can be done by strengthening ongoing initiatives, introducing new measures, training and capacity building. One of the main focus areas of the Climarice projects is to train the farmers on implementing various adaptation technologies that would increase the water and nutrient use efficiencies at field level. Climarice project scientists have identified various technologies such as usage of biofertilizers such as blue green algae and azolla to improve the nutrient use efficiency in paddy cultivation, application of green manures to enhance soil organic matter content, introduction of short duration rice cultivar during delayed monsoon, cultivation of alternate crops for income generation, System of Rice intensification for enhancing water and grain productivity, usage of bio control agents such as Trichoderma and Pseudomonas for eco friendly management of pest and diseases etc.,. For the successful implementation of these technologies at field level, the farmers have to be given with training and exposure visits. ClimaRice project scientists have undertaken many capacity building programmes to farmers of Cauvery basin on various adaptation technologies and these programmes have created confidence among the farmers. Many farmers who have attended the training programmes are following the technologies with great interest. A summary of the training programmes and their impact are furnished in this report.

Sammendrag

In the present study we evaluated the effect of phenological stage at harvest and drying temperature on the content of secondary metabolites in six year old cultivatedclones of Rhodiola rosea. The experimental work was performed in cooperation between MTT in Finland and Bioforsk in Norway. In spite of the differences in growing season, we found similar development in biomassproduction and content of secondary metabolites in the two field experiments.During the period with intensive shoot growth the dry weight of the rootdecreased until budding / full flowering followed by an increase towards thelast harvest after wilting. The % dry matter followed the same development. The content of total rosavins in the dry rhizomes was highest at flowering at both sitesand the average content for spring was 24 % respectively 21% higher than inautumn in Finland and Norway (P=0,002). In Finland the average content of salidroside in spring of the dry rhizomewas 68 % higher than in autumn. While in Norway there were no differences insalidroside content at the different phenological stages (P = 0,097), lowvariation in the content of cinnamic alcohol at both sites was observed, but atendency to a small increase after flowering. The content of total rosavins was significantly higher at drying temperatures at or below 50˚C (P

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This Technical brief is a short summary of the results obtained from the field trials conducted at Anbil Dharmalingam Agricultural College and Research Institute, Trichy, India during Rabi (2010-2011) to evaluate the role of photosynthetic diazotrophs in reducing methane flux from rice soil ecosystem as a part of climarice project. Global warming induced by increasing concentration of greenhouse gases (GHGs) in the atmosphere is a matter of great environmental concern. Methane, carbon dioxide, nitrous oxide and chlorofluorocarbon are the GHGs which have strong infrared absorption bands and trap part of the thermal radiation from the earth surface. Rice fields have to be considered as a significant source of greenhouse gases and rice field eco systems account for about 60 Tg methane per year or about 12 per cent of the global annual methane emission. The purpose of this study is to explore the potential of blue green algae and azolla in minimizing methane flux at source in paddy field ecosystem. In the present study, combined application of organics and blue green algae not only recorded higher yield, but also found to emit less methane in paddy cultivation than the application of organics alone.