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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.

2002

Abstract

The effect of cold acclimation and defence activators on snow mould resistance and expression of pathogenesis-related (PR-) genes were investigated in winter cereals and perennial ryegrass. Cold acclimation, known to induce snow mould resistance, had apotentiating effect on snow mould-induced PR-gene expression in winter wheat. Chitosan treatment induced chitinase expression and in some cases also snow mould resistance in winter wheat. Bion treatment reduced snow mould resistance in perennial ryegrass.

Abstract

Sheep and goat farming systems in this part of Europe are based on extensive use of non-fertilised natural pastures and a long barn-feeding period. One million ewes are kept for the production of meat and wool while 60,000 goats are kept mainly for themilk. The local demand for organic meat and milk is increasing gradually and 10 percent of the agricultural area is projected to be managed according to organic principles by 2010. This paper discusses the feasibility of introducing cashmere goats in an organic sheep farming production system, based on economical calculations in a Linear Programming model. Significant movements from sheep to cashmere goats production are entirely as slaughtering of eight months old kids (11 kg) is unprofitable, assuming equal labour input of goats and sheep. Yields of meat and cashmere could be improved by feeding the kids until 20 months (19 kg) so possibly making goats as profitable as sheep. The benefits of high value cashmere production and controlling bush encroachment by goats favour a mixed farming system. If yield-levels of roughage can be maintained at 75% without artificial fertilizers and challenges in housing of small ruminants are solved, a shift away from conventional farming is profitable given the current support for organic farming.

Abstract

In a greenery trial of Noble fir in western Norway, most branches had good quality until 1994 when 31 % of the branches were discarded. Since then a high level of losses has been noted and 87 % were discarded in 2000. A survey in 1998 revealed that the needle blight fungus Delphinella abietis was the main cause. It seems that frost did not initiate or maintain the disease in the stand, but generally low temperatures may have been important. Discarded branches with the fungus have been left on the ground and have probably been important in maintaining a high level of attack.

Abstract

Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) were measured on lumber from trees originating from four stands in each of the countries Norway and Sweden. Half of the stands were monocultures of Norway spruce while the remainder were mixed stands of Norway spruce and birch species.No significant differences in MOE and MOR were found between Norway spruce lumber grown in monocultures and lumber originating from mixed stands. Furthermore, there were no significant differences between the two groups concerning wood density, mean annual ring width and diameter of the largest knot in each log.These three variables also yielded similar models for lumber originating from monocultures and mixed stands, respectively, when used as independent variables in simple regression models for MOE and MOR.PLS1 regression models, with a X-matrix of variables measurable with simple equipment on trees and logs, were used to sort logs according to predicted values of MOE and MOR. The models show promising results with respect to pre-sorting of logs in order to create a better fit between the quality of logs and the expected properties of the final products.When sorting logs, a high percentage is correctly classified, and the cumulative distributions of the two groups resulting from sorting are clearly different. Hence, PLS1 regression models using simple measurements on trees and logs seems potentially useful for predictions of MOE and MOR without the use of advanced technical equipment.

Abstract

• Micro suction cups are useful for collecting soil solution at high spatial resolution, e.g. gradients in the rhizosphere. • Their success in the field depends on soil type and the soil water content. • Both inorganic ions, organic acids, and pH in the soil solution showed high variability through time. • Unexpectedly, the concentration of major cations and anions were higher in the rhizosphere than in the bulk soil. • Only four organic acids were detected with certainty, i.e. by use of retention times and spectra of known standards. • Low initial concentrations with subsequent microbial breakdown in the samples vials and analytical limitations of small volume samples are considered to be the main reasons for the small number of acids detected.