Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2007
Abstract
Empirical evidence that the N dissipation from dairy production depends tightly on the segregation of animals from plant production is provided
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No abstract has been registered
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No abstract has been registered
Abstract
The performance of the plum rootstocks Marianna, Pixy and Wangenheim using St. Julien A as a standard to the cultivars `Avalon", `Edda", `Excalibur", `Jubileum", `Reeves" and `Victoria" was assessed in a field trial in western Norway at 60" North. Trees were planted in spring 1999, the plant material was one-year-old whips, spaced 2.0 x 4.5 m and formed with a central leader as free spindles. Soil management was grass in the alleyways and herbicide strips 1-m wide along the tree rows. Tree vigour, yield, fruit size and yield efficentcy were evaluated for the six subsequent years. Tree size was significantly affected by the rootstocks after six years growth. Wangenheim produced the smallest and St. Julien A and Pixy the largest trees as measured by trunk cross-sectional area in average for the different cultivars. St. Julien A and Pixy were the most productive rootstocks for the cultivars. However, Pixy produced significant larger yields per tree to the cultivar `Reeves" than St. Julien A. Trees on Pixy were the most yield efficient for all cultivars with the exception of `Victoria". The fruit sizes were in general large for all cultivars and became little affected by the different rootstocks. Fruit quality characterized by the content of soluble solids was in general high and did not differ between trees on the various rootstocks. The cultivar `Avalon" had the highest contents of soluble solids.
Authors
Mekjell MelandAbstract
During the period 1998-2000, thinning trials were conducted using bloom thinners on mature European plum trees at Ullensvang and at fruit growers sites in western Norway. In 1998, unsprayed control and handthinned `Victoria" trees were compared with trees treated at full bloom with a single application of 1% Armothin® or 1.5% ammoniumthiosulphate (ATS). The same program was conducted in the following two years with the addition of a single full bloom treatment with 250 ppm ethephon and a post-bloom application one month after full bloom with the mixture 10 ppm 1-napththaleneacetic acid (NAA) and 75 ppm ethephon. High volume sprays were conducted the first two years and low volume the last year. Thinning trials testing 1-1.5 % ATS and 5-7 % lime sulphur in comparison with unthinned and handthinned trees to the cultivars `Opal" and `Victoria" were conducted in 2000, at growers sites. Generally, thinning treatments reduced crop load and enhanced fruit quality (fruit size, soluble solid content, fruit firmness and ground and surface colour), but the results varied from year to year. Fruit set was reduced to about half of control values and the percentage of class 1 fruits was doubled compared to the control trees. High volume sprays to running off was more effective than low volume. The cultivar `Opal" was more sensitive to ATS than `Victoria" and a low dosage recommended. All thinning compounds caused some minor leaf injury but no fruit damage. The flower thinners were efficient at rather low temperture. No differences in the amount of gummosis (internal disorder of the fruits) were observed due to treatments on the `Victoria" plums. Return bloom was improved by thinning. In conclusion, a single dilute application at full bloom of 1% Armothin®, 1.5% ATS or 250 ppm ethephon or one application of the mixture 10 ppm NAA-75 ppm ethephon four weeks after bloom reduced fruit set and crop load and increased the fruit quality and return bloom to the cultivar `Victoria". Similar results gave one dilute spray with 1 % ATS or 5 % lime sulphur at full bloom to the cultivar `Opal".
Abstract
Betre lystilhøve i frukttrea aukar veksten hjå tre og frukter, og fruktkvalitetsfaktorar som farge og oppløyst turrstoff vert betre. Sjølv om daglengda under norske veksttilhøve er lang, er den samla lystilgangen mindre enn på sørlegare breiddegrader pga den korte vekstsesongen. Metodar som aukar ljostilgangen, t.d. lysreflekterande duk under trea, vil vera gunstig for norsk fruktdyrking. Ein har prøvd ein voven plast duk (Extenday (R)) i frukthagar på Vestlandet. Der radavstanden var 4 m, har ein strekt ut 3m brei duk på bakken langs køyregangane og festa med gummiband til trea på kvar side. Der radavstanden var 5 m, nytta ein 4m brei duk. Duken låg ute frå midten av juni til etter hausting. Det var ingen temepratureffekt av duken. Men det var 5 gonger så mykje lys i trekruna hjå tre som sto i felt med reflekterande duk i høve til kontroll tre. I køyregangen var det 3 gonger så mykje lys over duk som i køyregangar med gras. I Aroma var eple frå tre frå felt med duk større, søtare og med meir raud dekkfarge enn frå kontroll trea. Det var særleg stor skilnad frå eple på dei nedte greinene. Med omsyn til fastleik og syreinnhald var det ikkje sikre skilnader. Men Streif-indeks viste at refleksduken framskunda mogninga.
Abstract
I eit felt med "Excalibur" og "Prinlew" plommer vart køyregangen dekka med kvit reflekterande duk for å betra ljostilhøva i trekruna. Duken låg i hagen frå 2 veker etter bløming til etter at plommene var hausta i midten av september. Der det ikkje var nytta reflekterande duk var fruktene nede på treet grønare, hadde mindre dekkfarge og lågare innhald av oppløyst turrstoff enn fruktene oppe i trekrunene. Fruktene frå tre som hadde stått over reflekterande duk var like godt farga og hadde same syrinnhald og fastleik om dei var hausta oppe eller nede på trea. Men det var også for desse trea høgare innhald av oppløyst turrstoff i fruktene oppe i trea i høve til dei som hadde vakse nedst i trea. Reflekterande duk gav jamnare mogning hjå plommene oppe og nede i trea. Dermed kan ein klara seg med færre haustingar. Temperaturen var ikkje heva der ein nytta duk, og duken svekka grasveksten i køyregangane.
Authors
Klaus Mittenzwei Wendy Fjellstad Wenche E. Dramstad Ola Flaten Arnt Kristian Gjertsen Maria Loureiro Sjur Spildo PrestegardAbstract
In recent years the objectives of agricultural policy have shifted from a principal focus on production and income towards agriculture\"s provision of public goods summarized by the term ‘multifunctionality\". Agricultural sector models, which are important tools for policy advice, need to be adjusted in order to maintain their relevance and reliability in accordance with policy changes. This paper investigates the strengths and limitations of incorporating multifunctionality indicators in the agricultural sector model Common Agricultural Policy Regional Impact Analysis (CAPRI) by reviewing the existing literature and incorporating such indicators in the model. Multifunctionality indicators are developed and implemented for four selected aspects of multifunctionality: food security, landscape, environmental concerns and rural viability. By running different policy reform scenarios, it is shown that indicators closely related to the underlying economic variables of the sector model may provide useful to describe the effects of policy reforms on agriculture\"s multifunctionality. However, these indicators do not completely cover the selected aspects of multifunctionality. In order to yield a broader coverage, this paper proposes to strengthen interdisciplinary research by linking agricultural sector models with other model systems like farm-based economical-ecological models, regional economic models or landscape information systems.
Abstract
Norwegian agriculture is totally dependent on a safe supply of seed of winter-hardy timothy varieties. The annual seed consumption varies depending on the extent of winter damages, particularly in northern Norway, and the average seed yield varies with weather and harvest conditions in the seed-producing districts in the southeastern and central part of the country. To buffer these variations, seed companies always keep stocks corresponding to 50-100 % of the average annual seed consumption. Such large stocks are risky to maintain as seed lots will loose germination over time. Our objective was to elucidate the effect of seed harvest time and seed storage location on the longevity of timothy seed. In 2003, timothy ‘Grindstad’ was combined directly on 2, 5 or 8 August corresponding to a seed moisture content (SMC) of 34, 27 and 20 %, respectively. After harvest the seed was dried to 10-11 % SMC. Germination analyses were accomplished 3, 15, 26 and 38 months after seed harvest; the three latter after splitting each seed lot into four sub-lots that were stored either in a conditioned seed store (4ºC, 30% RH), or in unconditioned warehouses at there climatically different locations. While seed harvest time had no effect on germination three months after harvest, differences became increasingly evident as time went by. After 38 months’ storage, seed stored in the conditioned store or in the warehouse at the continental location Tynset germinated, on average for harvest times, 15-16 units better than seed stored in the warehouse at the coastal location Vaksdal; and seed lots harvested at 20 % SMC germinated, on average for storage locations, 24 units better than seed harvested at 37 % SMC. While it has long been documented that direct combining at high SMC may damage seed germination, there has been less awareness that this damage may not manifest itself until after a certain storage period.
Abstract
Tiller demography and contribution to seed yield were studied in first year seed crops of smooth bromegrass (SB, Bromus inermis ‘Lofar’) and meadow fescue (MF, Festuca pratensis ‘Salten’) planted on different dates and with increasing plant densities (A: 15 Jun. / 11 plants m-2, B: 15 or 30 July / 44 plants m-2, C: 15 August or 10 September /178 plants m-2) in field trials at Landvik, SE Norway. While the total tiller population in most crops increased until seed harvest, it decreased during panicle elongation in crops of SB and MF that had reached 2000 and 3500 tillers m-2 in early spring, respectively. Except for the fact that many of the primary tillers of SB died after producing barren stems, tillers formed in August and September had the greatest chance of becoming reproductive and produced the heaviest inflorescences in both species. Most tillers produced in winter or early spring either remained vegetative or died, but spring-emerging tillers contributed up to 30% of the total seed yield in early-established, low-density crops of MF. It is concluded that spring-emerged tillers contribute more to seed yield in MF than in SB and more in seed crops established early at low plant density than in crops established late at higher density.