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Publikasjoner

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.

2018

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Sammendrag

1. Large-scale pattern-oriented approaches are useful to understand the multi-level processes that shape the genetic structure of a population. Matching the scales of patterns and putative processes is both a key to success and a challenge. 2. We have developed a simple statistical approach, based on variogram analysis, that identifies multiple spatial scales where the population pattern, in this case genetic structure, have highest expression (i.e. the spatial scales at which the strength of patterning of isolation-by-distance (IBD) residual variance reached maximum) from empirical data and, thus, at which scales it should be studied relative to the underlying processes. The approach is applicable to any spatially explicit pairwise data, including genetic, morphological or ecological distance or similarity of individuals, populations and ecosystems. To exemplify possible applications of this approach, we analysed microsatellite genotypes of 1,530 brown bears from Sweden and Norway. 3. The variogram approach identified two scales at which population structure was strongest, thus indicating two different scale-dependent processes: home-rangerelated processes at scales <35 km, and subpopulation division at scales >98 km. On the basis of this, we performed a scale-explicit analysis of genetic structure using DResD analysis and compared the results with those obtained by the Bayesian clustering implemented in structure. 4. We found that the genetic cluster identified in central Scandinavia by Structure is caused by IBD, with distinct gene flow barriers to the south and north. We discuss possible applications and research perspectives to further develop the approach.

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Forestry in coastal Norway has traditionally been a marginal activity with a low annual harvest rate. However, the region is now faced with large areas of spruce plantations that will reach harvest maturity within the next 25 years. Due to the poor infrastructure in the region, the current challenge is to harvest the maturing spruce plantations at an acceptable cost. Hence, there is considerable interest both from the forest sector and politicians to invest in infrastructure that can provide the basis for profitable forest sector development in coastal Norway. This paper presents a mathematical optimization model for timber transportation from stump to industry. The main decision variables are location of quays, upgrade of public road links, the length of new forest roads, and when the investments should happen. The main objective is to provide decision support for prioritization of infrastructure investments. The optimization model is combined with a dynamical forest resource model, providing details on available volumes and costs. A case study for coastal Norway is presented and solved to optimality. The instance includes 10 counties comprising more than 200 municipalities with forest resources, 53 possible new quays for timber export and 916 public road links that also can be upgraded. Compared with a no investment case, the optimal solution improved the objective by 23%. The study shows that consistent, informative and good analyses can be performed to evaluate trade-offs, prioritization, time and order of investment, and cost saving potentials of infrastructure investments in the forest industry. The solution seems reasonable based on present infrastructure and state of the forest.

Sammendrag

Norges marginale jordbruk og klima har satt sitt preg på våre mattradisjoner. Råvarene har vært tilgjengelige i relativt korte sesonger, og ofte i store mengder – f.eks. gjennom torskefiske, sildefiske, innhøsting av korn, opptak av potet og slakting av dyr. Behovet for å konservere råvarene til et helt års konsum, har derfor satt sitt preg på den norske matkulturen. Denne artikkelen berører norsk matkultur i selvbergingshusholdets tid. Selvbergingshusholdet ble i flere bygder holdt levende til langt utpå 1900-tallet, og fikk igjen aktualitet under andre verdenskrig. Tradisjoner basert på dette husholdet preger fortsatt dagens matkultur.

Sammendrag

Lunch canteens and their salad bars are an important arena for sales and consumption of vegetables including herbs. One major Norwegian canteen operator had a turnover of more than seven thousand tons of fresh vegetables in 2016, with lettuce, tomato, potato, cucumber and bell pepper being the most important species. A typical lunch meal included about 260 g vegetables including potatoes. Vegetables used in 450 canteens were either green, yellow, orange, red, purple/dark or colorless, and consisted of pigments of chlorophylls, carotenoids, anthocyanins and betalains. The total pigment content in the 60 most abundant vegetables was calculated to be 14.5-28.3 mg 100 g-1 FW. Of all vegetables in the canteens, 60% were found to be green. The intake of chlorophyll through one lunch meal was estimated to be 46 mg. Lettuce was found to be the single most important source of chlorophylls as this species was consumed in high amounts and made up 20% of the vegetables in a lunch meal. Carotenoids was found in all colored vegetables except the purple/dark ones and an estimate revealed an intake of 15 mg total carotenoids from lunch vegetables. Tomato was found to be the most important carotenoid source representing 44% of the total intake. Due to high pigment concentrations and popularity of red beets in the salad bars, the intake of betalains through a lunch meal was estimated to be 3 mg, similar to the total intake of anthocyanins from vegetable species.

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Seed from orchards, established from breeding programs, often dominate the planting stock in economically important tree species, such as Norway spruce. The genetic diversity in seed orchards’ crops depends on effective population size which in turn is affected by many factors such as: number of parents in the orchard, seed orchards’ design, fecundity, and pollen contamination. Even though seed orchards’ seed is extensively used over large regions, very few studies have addressed how well their crops reflect the genetic diversity present in the regions where they are planted. Here we have investigated the genetic diversity (by means of 11 microsatellites) of two Norway spruce seed orchard populations with different number of parents (60 and 25) and compared this with seed crops collected in the semi natural forest and natural unmanaged populations. We found that the ratio between the effective population size (N e ) and actual number of parents (N) varied between 0.60 and 0.76 in the orchards’ seedlots. A reduction in genetic diversity (mainly allelic richness) was detected in a few seedlots, mainly where the number of parents was low. Our results also show that pollen contamination play an important role in maintaining the genetic diversity in orchards’ seedlots, particularly when the number of parents is low. The population genetic structure among seed orhcards and natural populations is shallow suggesting that re- generation with seed from current seed orchards will have limited effect on the overall genetic diversity.

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Most horticultural crops are attacked by more than one insect pest. As broad-spectrum chemical control options are becoming increasingly restricted, there is a need to develop novel control methods. Semiochemical attrac- tants are available for three important horticultural pests, strawberry blossom weevil, Anthonomus rubi Herbst (Coleoptera: Curculionidae), European tarnished plant bug, Lygus rugulipennis Poppius (Hemiptera: Miridae) and raspberry beetle, Byturus tomentosus deGeer (Coleoptera: Byturidae). Traps targeting more than one pest species would be more practical and economical for both monitoring and mass trapping than traps for single-species. In this study we aimed to (1) improve the effectiveness of existing traps for insect pests in strawberry and raspberry crops by increasing catches of each species, and (2) test if attractants for two unrelated pest species could be combined to capture both in the same trap without decreasing the total catches. Field tests were carried out in four European countries and different combinations of semiochemicals were compared. A volatile from straw- berry flowers, 1,4 dimethoxybenzene (DMB), increased the attractiveness of the aggregation pheromone to both sexes of A. rubi. The host-plant volatile, phenylacetaldehyde (PAA), increased the attraction of female L. rugu- lipennis to the sex pheromone, and, in strawberry, there was some evidence that adding DMB increased catches further. Traps baited with the aggregation pheromone of A. rubi, DMB, the sex pheromone of L. rugulipennis and PAA attracted both target species to the same trap with no significant difference in catches compared to those single-species traps. In raspberry, catches in traps baited with a combination of A. rubi aggregation pheromone, DMB and the commercially available lure for B. tomentosus, based on raspberry flower volatiles, were similar to those in single-species traps. In both crops the efficiency of the traps still needs improvement, but the multi- species traps are adequate for monitoring and should not lead to confusion for the user as the target species are easy to distinguish from each other.

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Sammendrag

Throughout history, man has strongly utilized and affected forest genetic resources in Europe. From an evolu-tionary perspective deforestation/fragmentation (→genetic drift), transfer of seeds and plants to new environ-ments (→mainly gene flow) and selective logging (→selection) are most relevant and have been particularlyaddressed in this review. In contrast to most conifers, broadleaved tree populations have been especially reducedby historic fragmentation, and consequently, the related genetic effects have been possibly more pronounced.Widespread wind-pollinated species with wind/animal dispersed seeds appear to be more resilient to frag-mentation than species with e.g. small geographic ranges and gravity dispersed seeds. In addition, naturallyfragmented populations in the range margins may be more vulnerable than central populations as conditions forgene flow are generally impaired in peripheral areas. Traits important for adaptation (e.g. bud burst, bud set) arecontrolled by many genes, and as a corollary of fragmentation such genes are lost at a low rate. Large scalecommercial translocation of seeds and plants for forestry purposes applies mostly to conifers and dates backabout two centuries. Although many translocations have been successful in a forestry perspective, exposure tonew selective regimes has sometimes challenged the adaptive limits of populations and caused setbacks or evendiebacks of populations, as well as influencing neighbouring populations with maladapted genes (e.g. Scots pine,maritime pine, larch). Many tree species have substantial plasticity in fitness-related traits, which is vital forsurvival and viability following translocations. Selective logging has been practiced in Europe over the last twocenturies and implies removal of superior trees with respect to growth and quality. Such traits are partly undergenetic control. Consequent removal of superior trees may therefore have negative effects on the remaining genepool, but this effect will also be counteracted by extensive gene flow. Although humans have strongly affectedEuropean forest trees over the last millennia, we argue that they are still resilient from an evolutionary perspective.