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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.

2009

Sammendrag

The common European cerambycid Leiopus nebulosus (Linnaeus, 1758) is herein split into two sibling species. The male genitalia characters, as well as spermathecae in females, were examined and found to provide strong support for this separation. A new species, Leiopus linnei sp. nov., is based on specimens mainly from Scandinavia. The establishment of the new species is supported by DNA barcoding of Scandinavian specimens of L. nebulosus, L. linnei sp. nov., and L. punctulatus (Paykull, 1800). There are significant genetic differences between all these species. The geographical distribution and the bionomy of L. nebulosus and L. linnei sp. nov. are described. The type of Cerambyx nebulosus Linnaeus, 1758 is lost. A neotype of Cerambyx nebulosus, currently Leiopus nebulosus (Linnaeus, 1758), is designated and a redescription of L. nebulosus is presented. A key for the identification of L. nebulosus and L. linnei sp. nov. is provided. The varieties L. nebulosus var. dissimilis Pic, 1889, L. nebulosus var. unifasciatus Pic, 1891, and L. nebulosus var. siculus Pic, 1924 are considered as junior synonyms, syn.nov. of L. nebulosus.

Sammendrag

A cost efficient use of harvesting resources is important in the forest industry. The main planning is made in an annual resource plan which is continuously revised. The harvesting operations are divided into harvesting and forwarding. The harvesting operation fells trees and put them in piles in the harvest areas. The forwarding operation collects piles and moves them to storage locations adjacent to forest roads. These operations are done by machines (harvesters, forwarders and harwarders) and these are operated by crews living in cities/villages which are within some maximum distance from the harvest areas. Machines, harvest teams and harvest areas have different characteristic and properties and it is difficult to come up with the best possible match throughout the year. The aim with the planning is to come up with a cost efficient plan The total cost is based on three parts; production cost, traveling cost and moving cost. The production cost is the cost for the harvesting and the forwarding. The traveling cost is the cost for driving back and forward (daily) to the harvest area from the home base. Moving cost is associated with moving the machines and equipment between harvest areas. The Forest Research Institute of Sweden has together with a number of Swedish forest companies developed a decision support platform for the planning. An important aspect is to come up with high quality plans within short computational time. A central part is an optimization model which integrates assignment of machines to harvest areas and scheduling of the harvest areas during the year for each machine. The problem is complex and we propose a two phase solution method where we first solve the assignment problem and in a second stage the scheduling. In order be able to control the scheduling also in phase 1, we have introduced an extra cost component which balances the geographical spread of the assignments in phase 1. We have tested the solution approach on a case study from one of the larger Swedish forest companies. This case study involves 46 machines and 968 harvest areas representing a log volume of 1,33 million cubic meters. We describe some numerical results and experiences from the development and tests.

Sammendrag

The main objectives under this programme were: - To improve organising, content and quality of academic education and research in agriculture, veterinary medicine and forestry to meet with needs for qualified people in ongoing rebuilding after wars and to reach the general European level and standards. - Create functional and sustainable networks of regional institutions and professionals to support each other and cooperate for optimal use of limited available resources in the SEE region in a difficult rebuilding situation. The main activities were: - Research and development projects in the areas of animal sciences, crop and fodder production and use of GIS-methods in forestry and agriculture. - Support to development of staff and institutions in form of study stays, study material, covering of costs for laboratory analysis etc. related to M.Sc. and Ph.D. thesis work, guest lecturing and some equipment. - Support to reorientation of academic education in agriculture, forestry and veterinary medicine. - Support to regional networks, professional meetings, further development and use of the Programme web site and web-based teaching. The most important strategy in this Programme was to facilitate for institutional cooperation and network building between partners in the SEE area. Therefore a broad approach was chosen with a large number of partners (16) from all actual geographical areas in SEE - West Balkan - (Albania, Bosnia & Herzegovina, Croatia, Kosovo, Macedonia and Serbia & Montenegro) and representing most of the different ethnical groups in the region. The main intensions under the new programme is to improve the organisation, content and quality of academic education, research and support services in the faculties of agriculture, veterinary medicine and forestry in order to meet national needs in the ongoing reconstruction after the regional wars. Programme activities include activities that: ? Support and strengthen selected institutions in SEE/WB towards obtaining European professional levels and standards. ? Promote networking and scientific cooperation between the SEE/WB institutions. ? Promote networking and scientific cooperation between institutions in SEE/WB and in Norway.

Sammendrag

Neozygites floridana is a fungus in the order Entomophthorales that is a natural enemy of several spider mite species including the two-spotted spider mite, Tetranychus urticae. When conditions are right, this fungus may cause epizootics in spider mite populations and kill high numbers of mites. The fungus is therefore promising for biological control of T. urticae in strawberry and can be used in combination with other pest management strategies. Our previous studies have shown that N. floridana is compatible with other biocontrol methods such as predatory mites. Phytoseiulus longipes fed on fungus-infected T. urticae laid equal number of eggs to those fed on healthy prey. This indicates that the fungus does not affect this predatory mite negatively. In a choice experiment (hosts with and without N. floridana), P. longipes fed indiscriminately irrespective of the presence of the fungus. The compatibility of biological control methods with pesticides is of great importance for an integrated pest management system to work well. Some acaricides and fungicides have the potential to affect both beneficial fungi and predatory mites and careful selection of pesticides that are not harmful to these beneficial organisms can promote their biocontrol potential. Our studies have shown that the fungicides captan, mancozeb, tolylfluanid, fenhexamid, cyprodinil + fludioxonil affect N. floridana in a way that may be detrimental to the biocontrol potential of this beneficial fungus in the field. Use of resistant varieties is also important in integrated pest management because pests are known to be more vulnerable to pathogens if they feed on poor or resistant plants and our studies on effects of host plants of spider mites confirms this.

Sammendrag

Neozygites floridana is a fungus in the order Entomophthorales that infects and kills the two-spotted spider mite, Tetranychus urticae. The fungus is therefore of interest in the biological control of T. urticae. To obtain information that might help in the use of this fungus under practical conditions in strawberries and cucumbers we have tried to answer the following questions in a series of studies: 1) When, and at what infection levels does N. floridana occur in T. urticae populations in field grown strawberries in Norway? 2) How does N. floridana survive harsh climatic conditions (i.e winter) in Norway? 3) Where do N. floridana infected T. urticae move and sporulate on a plant? 4) How can N. floridana be inoculated in augmentative microbial control of T. urticae? Results show that the N. floridana infection level varies considerably throughout a season. T. urticae killed by N. floridana was found to sporulate surprisingly early in the season (first observation March 18) and infection early in the season is important for a good control of T. urticae. N. floridana was observed to over-winter as hyphal bodies in hibernating T. urticae females throughout the winter. Cadavers with resting spores were found from October to the end of January only. Cadavers then probably disintegrated, and resting spores were left on leaves, soil, etc. In a bioassay where a Norwegian N. floridana isolate was tested for numbers and distance of spores thrown at three different temperatures relevant to Norwegian conditions (13o, 18o, 23o C), results show that the highest numbers of spores (1886 and 1733 per cadaver) were thrown at 13o and 18o compared to 23o C (1302 per cadaver). Spores were thrown at the same distance (up to about 6 mm) at all three temperatures. These results show that the fungus may be a promising agent at temperatures relevant for strawberry production in countries located in Northern areas. Our attempt to inoculate N. floridana artificially in a strawberry field and also in greenhouse cucumbers has not been successful yet, but we are working to improve the methods in a new project titled "BERRYSYS -A system approach to biocontrol in organic and integrated strawberry production".