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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.

2007

Abstract

The application of plant growth regulators (PGRs) and insecticides, either alone or in tank mixture, was tested in nine on-farm trials laid out according to three different experimental plans in SE Norway (59-61ºN) from 2002 to 2006. The first plan compared the PGRs trinexapac-ethyl (125 or 250 g a.i. ha-1), chlormequat chloride (2000 g a.i. ha-1) and ethephon (240 g a.i. ha-1) applied on two dates and compared with an untreated check. On average for three trials, seed yield of the diploid cv. Nordi (origin 61ºN) increased 15 % by application of trinexapac-ethyl (250 g a.i. ha-1) at stem elongation, decreased 18 % by application of ethephone at flower bud emergence, and was not significantly affected by any of the other treatments. The diploid cv. Bjursele (two trials) and the tetraploid cv. Betty (one trial) showed no response to any of the PGRs. In the second experimental plan, laid out in two seed crops of the diploid cv. Lea in 2005, trinexapac-ethyl (125 or 250 g a.i. ha- 1) was applied alone or in tank mixture with the insecticides alpha-cypermethrin (20 g a.i. ha-1) or dimethoate (500 g a.i. ha-1) on two dates. These trials verified the positive effect of trinexapacethyl, but the insecticides had no significant effect, which is not surprising as no harmful insects were detected. The third experimental plan compared insecticides at two developmental stages in a seed crop of cv. Lea with a high occurrence of Apion seed weevil and the lesser clover leaf weevil Hypera nigrirostris. In this trial, alpha-cypermethrin increased seed yield by 14 % when applied at flower bud emergence. Effective from 2004, Moddus 250 EC (trinexapac-ethyl) was approved in Norwegian seed production of selected cultivars of red clover. Research is still underway to evaluate the need for control of various weevils.

Abstract

Many demand and supply-side policies impede or foster forestry entrepreneurship. A study was conducted to consolidate existing knowledge on policies influencing forestry entrepreneurship in Finland, Norway, Japan, Australia, the Philippines and the USA, and to draw conclusions on these impeding and fostering factors. From the country studies it was difficult to find common structures on policies affecting forestry entrepreneurship. This is understandable because most policies in forestry are aimed at supporting sustainable forest management, wood production and ecological services of the forests rather than entrepreneurship as such. Despite the high variety of policies applied in the study countries, it can be concluded that strict public control on forests? use and management potentially impedes forestry entrepreneurship. While these policies assist to correct market failure and to promote sustainability of forest management, they may also result into unnecessary and ineffective regulations that limit the opportunities for forestry entrepreneurship. A common feature promoting the demand for forestry entrepreneurship in some of the countries studied is the strong emphasis on forestry cooperatives, which were important institutions to support small-scale forestry entrepreneurship. In many study countries, different ad hoc programs are implemented to find new economic and entrepreneurial opportunities aside from the current use of wood and forests. Subsidies and tax incentives are commonly applied to reduce risks from making forestry investments or otherwise increase the economic return from timber production.

Abstract

The egg parasitoid O. epuhts and the pupal parasitism caused by the P. foveolatus and Mesopolobus spp. were the key mortality factors in the population dynamics of the C. similis. The egg and pupal parasitism were density dependant at two and one locality, respectively. (c) 2007 Elsevier Ltd. All rights reserved.

Abstract

Furfurylated wood is an environmentally friendly, chemically treated, wood product with improved characteristics. Quality control of furfurylated wood is still performed manually by subtracting the initial weight of a treated sample from its final weight, then dividing the result by the initial weight. Expressed as a percentage, this results in a value that represents the weight percent gain (WPG) of the treated sample and thus the degree of modification. The major disadvantage of this quality control method is that the production parameters are needed to determine WPG, since the initial weight cannot be deduced from a treated wood sample. In this paper the use of ThermoGravimetric Analysis (TGA) is presented as a potential quality control method for furfurylated Scots pine (Pinus sylvestris L.). The technique is independent of production parameters and, therefore, enables third parties to determine the WPG of any furfurylated wood product. Three validation trials have been performed with the same validation samples, but varying TGA settings and with different Partial Least Square regression models (PLS-models). Although the method needs further improvement, it has shown good accuracy and precision. Therefore, it is con