Våre poenggivende vitenskapelige publikasjoner

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2020 (64)

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To understand the thermal plasticity of a coastal foundation species across its latitudinal distribution, we assess physiological responses to high temperature stress in the kelp Laminaria digitata in combination with population genetic characteristics and relate heat resilience to genetic features and phylogeography. We hypothesize that populations from Arctic and cold-temperate locations are less heat resilient than populations from warm distributional edges. Using meristems of natural L. digitata populations from six locations ranging between Kongsfjorden, Spitsbergen (79°N), and Quiberon, France (47°N), we performed a common-garden heat stress experiment applying 15°C to 23°C over eight days. We assessed growth, photosynthetic quantum yield, carbon and nitrogen storage, and xanthophyll pigment contents as response traits. Population connectivity and genetic diversity were analyzed with microsatellite markers. Results from the heat stress experiment suggest that the upper temperature limit of L. digitata is nearly identical across its distribution range, but subtle differences in growth and stress responses were revealed for three populations from the species’ ecological range margins. Two populations at the species’ warm distribution limit showed higher temperature tolerance compared to other populations in growth at 19°C and recovery from 21°C (Quiberon, France), and photosynthetic quantum yield and xanthophyll pigment responses at 23°C (Helgoland, Germany). In L. digitata from the northernmost population (Spitsbergen, Norway), quantum yield indicated the highest heat sensitivity. Microsatellite genotyping revealed all sampled populations to be genetically distinct, with a strong hierarchical structure between southern and northern clades. Genetic diversity was lowest in the isolated population of the North Sea island of Helgoland and highest in Roscoff in the English Channel. All together, these results support the hypothesis of moderate local differentiation across L. digitata's European distribution, whereas effects are likely too weak to ameliorate the species’ capacity to withstand ocean warming and marine heatwaves at the southern range edge.

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Agricultural practices to improve yields in small‐scale farms in Africa usually focus on improving growing conditions for the crops by applying fertilizers, irrigation, and/or pesticides. This may, however, have limited effect on yield if the availability of effective pollinators is too low. In this study, we established an experiment to test whether soil fertility, soil moisture, and/or pollination was limiting watermelon (Citrullus lanatus) yields in Northern Tanzania. We subjected the experimental field to common farming practices while we treated selected plants with extrafertilizer applications, increased irrigation and/or extra pollination in a three‐way factorial experiment. One week before harvest, we assessed yield from each plant, quantified as the number of mature fruits and their weights. We also assessed fruit shape since this may affect the market price. For the first fruit ripening on each plant, we also assessed sugar content (brix) and flesh color as measures of fruit quality for human consumption. Extra pollination significantly increased the probability of a plant producing a second fruit of a size the farmer could sell at the market, and also the fruit sugar content, whereas additional fertilizer applications or increased irrigation did not improve yields. In addition, we did not find significant effects of increased fertilizer or watering on fruit sugar, weight, or color. We concluded that, insufficient pollination is limiting watermelon yields in our experiment and we suggest that this may be a common situation in sub‐Saharan Africa. It is therefore critically important that small‐scale farmers understand the role of pollinators and understand their importance for agricultural production. Agricultural policies to improve yields in developing countries should therefore also include measures to improve pollination services by giving education and advisory services to farmers on how to develop pollinator‐friendly habitats in agricultural landscapes.

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Due to their unique flora, hydrology and environmental characteristics, peatlands are precious and specific habitats for microorganisms and microscopic animals. Their microbial network structure and their biomass are crucial for peatland carbon cycling, through primary production, as well as decomposition and mineralization of organic matter. Wetlands are one of the ecosystems most at risk from anthropogenic activities and climate change. Most recent scenarios of climate change for Central Europe predict an increase in air temperature and a decrease in annual precipitation. These changes may disturb the biodiversity of aquatic organisms, and the peat carbon sink. Considering the above climatic scenarios, we aimed to: i) assess the response of microbial community biomass to warming and reduced precipitation through the lens of a manipulative experiment in a peatland ecosystem ii) predict how global warming might affect microbial biodiversity on peatlands exposed to warmer temperatures and decreased precipitation conditions. Additionally, we wanted to identify ecological indicators of warming among microorganisms living in Sphagnum peatland. The result of a manipulative experiment carried out at Rzecin peatland (W Poland) suggested that the strongest reduction in microbial biomass was observed in heated plots and plots where heating was combined with a reduction of precipitation. The most pronounced changes were observed in the case of the very abundant mixotrophic testate amoeba Hyalosphenia papilio and cyanobacteria. Shifts in the Sphagnum microbial network can be used as an early warning indicator of peatland warming, especially a decrease in the biomass of important phototrophic microbes living on the Sphagnum capitula, e.g. Hyalosphenia papilio.

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Understanding the factors that determine species’ resistance to environmental change is of utmost importance for biodiversity conservation. Here we investigated how the abundances of marshland species are determined by niche properties and functional traits. We re-surveyed 150 vegetation plots that were first surveyed in 1973 in order to explore species abundance changes over time. We found that the mean water level in the habitats of most studied species decreased significantly from 1973 to 2012. Nine of 17 target species were identified as abundance decreasing species and the other eight as abundance increasing species. The comparisons of seven plant characteristics (niche position water level, plant height, and five leaf traits) showed that the decreasing species had a significantly higher value of optimum water level and marginally significantly lower leaf N contents and specific leaf area (SLA) than those in increasing species. The stepwise regression analysis showed that optimum water level and leaf N were the best predictors of abundance changes of marsh plant species, as well as that the effect of optimum water level was stronger than that of leaf N. Our findings demonstrated that niche properties may be important for forecasting changes in wetland plant communities over time.

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Diseases caused by viruses threaten the production industry and food safety of aquaculture which is a great animal protein source. Grass carp reovirus (GCRV) has caused tremendous loss, and the molecular function of viral proteins during infection needs further research, as for most aquatic viruses. In this study, interaction between GCRV major outer capsid protein VP4 and RIG-I, a critical viral RNA sensor, was screened out by GST pull-down, endogenous immunoprecipitation and subsequent LC-MS/MS, and then verified by co-IP and an advanced farred fluorescence complementation system. VP4 was proved to bind to the CARD and RD domains of RIG-I and promoted K48-linked ubiquitination of RIG-I to degrade RIG-I. VP4 reduced mRNA and promoter activities of key genes of RLR pathway and sequential IFN production. As a consequence, antiviral effectors were suppressed and GCRV replication increased, resulting in intensified cytopathic effect. Furthermore, results of transcriptome sequencing of VP4 stably expressed CIK (C. idella kidney) cells indicated that VP4 activated the MyD88-dependent TLR pathway. Knockdown of VP4 obtained opposite effects. These results collectively revealed that VP4 interacts with RIG-I to restrain interferon response and assist GCRV invasion. This study lays the foundation for anti-dsRNA virus molecular function research in teleost and provides a novel insight into the strategy of immune evasion for aquatic virus.

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Within the last decade, implementing eight key principles of Integrated Pest Management (IPM) has become mandatory for all professional users of pesticides in the European Union (EU) and European Economic Area (EEA). Meanwhile, evidence of the level of implementation is lacking. In this study, the adoption of IPM principles among Norwegian grain farmers was measured using a novel IPM index based on self-reported levels of performing IPM practices. Three IPM experts weighted the principles and practices included in the index. They found prevention and suppression to be the most important principle, followed by monitoring and decisionmaking, while pesticide selection and evaluation were deemed least important. A survey of 1250 farmers showed that the principles with the highest adoption rates were evaluation and anti-resistance strategies, while non-chemical methods and reduced pesticide use had the lowest adoption rates. The results support previous suggestions that more complex principles, requiring a larger set of practices, are less readily adopted than those that are less complex. Nevertheless, the index scores showed that most Norwegian grain farmers are extensively practicing IPM; 75% of the respondents obtained scores between 60 and 80 on a 100-point scale, with an average score of 68. In the Norwegian context, it is more relevant to discuss the varying use of IPM rather than how to increase adoption in general.

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Nordic water bodies face multiple stressors due to human activities, generating diffuse loading and climate change. The ‘green shift’ towards a bio-based economy poses new demands and increased pressure on the environment. Bioeconomy-related pressures consist primarily of more intensive land management to maximise production of biomass. These activities can add considerable nutrient and sediment loads to receiving waters, posing a threat to ecosystem services and good ecological status of surface waters. The potential threats of climate change and the ‘green shift’ highlight the need for improved understanding of catchment-scale water and element fluxes. Here, we assess possible bioeconomy-induced pressures on Nordic catchments and associated impacts on water quality. We suggest measures to protect water quality under the ‘green shift’ and propose ‘road maps’ towards sustainable catchment management. We also identify knowledge gaps and highlight the importance of long-term monitoring data and good models to evaluate changes in water quality, improve understanding of bioeconomy-related impacts, support mitigation measures and maintain ecosystem services.

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European plum cultivars (Prunus domestica L.) are hexaploid and partially self-fertile or self-sterile requiring compatible pollinizers with overlapping bloom times. Therefore, inter-planting of different pollinizer cultivars is recommended. In order to identify successful pollinizers of the plum cultivars ‘Edda’, ‘Opal’ (self-fertile), ‘Jubileum’, ‘Reeves’, ‘Mallard’, ‘Avalon’, ‘Cacanska Lepotica’ (self-fertile), and ‘Valor’, 60 fruits per cultivar were collected from nine orchards in 2017 and 2018, all of which were located in Ullensvang, western Norway. DNA extraction was subsequently conducted from the obtained embryos, followed by genetic characterization using seven microsatellite markers. Tissue samples from all possible pollinizers were collected during the summer of 2017 and the same DNA approach was conducted. Results showed that ‘Opal’ was the most successful pollinizer among the investigated plum cultivars. The main exception was ‘Cacanska Lepotica’, which consistently displayed very high level of self-pollination. The most successful foreign pollinizer of ‘Opal’ was ‘Mallard’. However, in more than two thirds of embryos extracted from ‘Opal’ fruits self-fertilization was determined. ‘Reeves’ was identified as the most successful pollinizer among embryos collected from ‘Valor’. Among the five cultivars (‘Edda’, ‘Jubileum’, ‘Reeves’, ‘Mallard’, and ‘Avalon’) that did not display self-pollination, the pollinizer success rate of ‘Opal’, ranged from 36.5% (‘Mallard’) to 93.5% (‘Edda’) in 2017, while in 2018 this rate ranged from 43.5% (‘Jubileum’ and ‘Reeves’) up to 96.5% (‘Edda’). Overall, genotyping embryos using SSRs (simple sequence repeats) proved an effective method in determining the success rate of individual pollinizers among European plum cultivars.

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Four raspberry cultivars were grown at two different latitudes namely in Geisenheim (DE, 49°60’N; 7°57’E) and in Kapp (NO, 60°42’N; 10°52’E) to investigate the impact of these growing sites on primary and secondary fruit chemical ingredients in the 2017 season. Fruits were harvested at two picking dates each with three field replications. Contents of °Brix, glucose, fructose, sucrose, organic acids, ascorbic acid, polyols, total polyphenols, and anthocyanins were analyzed in the fruits. The geographic growing sites, which in this case is more than10 latitudes between HGU in Germany and NIBIO in Norway, has partly no, partly significant effects on the primary and secondary ingredients of the investigated raspberry cultivars. In respect to the created data set, temperatures shortly before or at the picking dates were not considered. It may be expected that temperatures at harvest have an effect on the fruit ingredients and therefore on a further classification of the samples.

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Growth cessation and floral initiation in black currant and red raspberry are jointly controlled by the interaction of temperature and short-day (SD) conditions, and the processes coincide in time in both natural and controlled environments. The critical photoperiods for the two successional responses were found to be approximately 15 and 16 h, respectively, for a range of Western-European black currant cultivars. Both cessation of growth and floral initiation are promoted and enhanced by increasing temperature in the 9 to 24°C range. In contrast, biennial-fruiting red raspberry has a maximum temperature limit for growth cessation and floral initiation. At temperatures above 16°C, most cultivars grow and remain vegetative regardless of day length conditions, at 12 to 16°C they cease growing and initiate flower primordia in photoperiods <15 h, while at temperatures ≤12°C they cease growing and initiate floral primordia regardless of day length. In the annual-fruiting (primocane) types of red raspberry on the other hand, floral initiation is not constrained by high temperature, but readily takes place at temperatures up to 30°C. In addition, floral initiation is also enhanced by long day (LD) conditions in most of these cultivars. Another fundamental physiological difference is that while floral primordia of the biennial types become dormant after initiation, they proceed directly to anthesis in the annual-fruiting types. Chilling at -5°C, and in the -5 to +5°C temperature range were found to be optimal for breaking of bud dormancy and promotion of flowering in black currant and red raspberry, respectively. In black currant, 14 weeks of chilling were optimal, while for raspberry, 20 or more weeks were required for full dormancy release and promotion of flowering along the entire length of the raspberry cane. The consequences of climate warming for the production of these species in different climatic regions are discussed.

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The triploid pear cultivar ‘Ingeborg’ is currently the main commercial pear cultivar grown in Norway. However, fruit set and subsequent yields of this cultivar have proven to be variable and overall rather low. In order to promote the fruit set, different bioregulators were applied during and after bloom and compared with an untreated control. Investigations were done during the period 2017-2018, at NIBIO Ullensvang, western Norway. Different dosages of both gibberellins (GA3, trade name GIBB 3, 10% active ingredient (a.i.) and GA4/7, trade name Novagib®, 1% a.i.) were applied at full bloom and at petal fall. Additional applications of the growth retardant prohexadioneCa (trade name Regalis®, 10% a.i.) were applied twice, when bourse shoots had 3-5 leaves and after one month later. Ethephon (Cerone (480 g a.i. L-1)) was applied three times starting about 7 days after petal fall with ca. 7- to 10-day intervals. All gibberellin applications significantly increased fruit set compared to the untreated control. One single application with GA3 (3 g ha-1) almost tripled the fruit number per 100 flower clusters when compared with the control (136 and 46, respectively). The yield response was similar (16.8 to 9.6 kg tree-1, respectively). Similar results occurred with one application of GA4/7 (12 g ha-1) with the same crop load level, and the fruit weights were similar to the control (130 g). Prohexadione-Ca treatments significantly reduced shoot growth of the pear trees. Two treatments with 125 g ha-1 or one treatment of 250 g ha-1 reduced the growth by ~35% but had no significant effect on fruit set and yield. The multiple ethephon applications (275 mL ha-1 in total) had no effect on both set and shoot growth, and return bloom compared to the untreated or gibberellin treated trees.

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In order to identify successful pollinizers of plum cultivars ‘Edda’ and ‘Opal’, 60 mature open pollinated fruit were collected from these two cultivars in autumn 2017. The fruits were harvested in three different orchards located in Ullensvang, the main fruit production area in Norway. After the harvest, kernels were separated from the fruit and used for the extraction of single embryos located within each kernel. At the same time, leaves were collected from the plum cultivars ‘Edda’ and ‘Opal’, as well as from all other plum cultivars present at the location and nearby orchards (‘Mallard’, ‘Jubileum’, ‘Reeves’, ‘Avalon’, ‘Valor’, ‘Cacanska Lepotica’ and ‘Herman’). DNA extraction was carried out for the embryos and leaves, and were used for genotyping using seven microsatellite markers. The microsatellite data were used for conducting paternity analyses based on a log likelihood ratio, where the fingerprint information from the leaves were the possible pollen donors available at the location. The results revealed within all examined orchards that the most successful pollinizer of ‘Edda’, a self-sterile cultivar, was ‘Opal’. The most successful foreign pollinizer of ‘Opal’ was ‘Mallard’. However, more than two thirds of embryos extracted from ‘Opal’ fruits did not present any alleles not already identified in ‘Opal’, which was expected considering that this plum cultivar was known to be self-fertile. European plums are hexaploid making its allele callings and paternity tests rather complicated. However, the approach used in this study gave clear answers regarding the most successful pollinizers.

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After harvest, vegetables go from storing assimilates to break down of assimilates and it is of crucial importance to slow down this process. Controlling the pre-storage period may contribute to maintain high quality in root vegetables during long-term storage. The aim of this 2-years study was to investigate the effect of seven different pre-storage strategies (direct to 0°C vs. down 1°C per day vs. 0.2°C temperature reduction per day and wound healing at 10°C with low/high humidity) on root storability in four cultivars of carrot (Daucus carota subsp. sativus) stored in 2016/2017/2018, swede (Brassica napus) in 2017/2018 and celeriac (Apium graveolens var. rapaceum) in 2017/2018. Mass loss and disease incidences were determined during and after long-term storage (6-7 month) in small-scale stores. Wound healing with low humidity resulted in larger mass loss than the other preharvest strategies in carrot and celeriac. In carrot, slow temperature reduction (0.2°C per day) also resulted in larger mass loss than the other strategies. Significantly higher numbers of infected roots, dominated by licorice rot (Mycocentrospora acerina), tip rot and gray mold (Botrytis cinerea), occurred in carrots stored at 0°C immediately compared to roots with a period of wound healing and slow temperature decline. In celeriac, the incidence of gray mold (Botrytis cinerea) and licorice rot (Mycocentrospora acerina) were significantly reduced with wound healing at low humidity. Storage quality of swede was not affected by pre-storage strategies. This study shows that prestorage strategies affect mass loss and disease incidence in celeriac and carrot during and after long-term storage.

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There is a need both in organic farming and on farms using integrated pest management for non-chemical measures that control the perennial weed flora. The effect of mechanical weeding and fertilisation on perennial weeds, fungal diseases and soil structure were evaluated in two different experiments in spring cereals. Experiment I included six strategies. The first strategy was (1) without specific measures against perennial weeds. The other strategies encompassed one or two seasonal control measures; (2) rhizome/root cutting with minimal soil disturbance in autumn, (3) hoeing with 24 cm row spacing, (4) combined hoeing and disc harrowing in autumn, (5) ‘KvikUp’ harrowing in spring, and (6) ‘KvikUp’ harrowing in spring and autumn. Experiment II included factor (i) inter-row hoeing and (ii) fertilisation level. This experiment included the comparison between normal row spacing (12 cm) with weed harrowing versus double row spacing (=24 cm) in combination with inter-row hoeing and 4 fertilisation levels (50–200 kg N ha−1). In experiment I the strategies consisting of no or one direct weed control measure (1, 2, 3 and 5) clearly did not control the perennial weeds. The two seasonal control measures (4 and 6) gave a satisfactory weed control and highest crop yield. The combination of best weed control and no measured harmful effects on soil structure or increase of fungal diseases may explain the highest yields for these strategies. In Experiment II, hoeing and 24 cm spacing gave less perennial biomass compared to 12 cm spacing. Grain yields increased linearly with increasing nitrogen input. The study shows that both inter-row hoeing and weed harrows, are important elements in integrated pest management practice and organic farming. In addition, our results indicate that efficient mechanical weeding is possible without harmful effects in crop rotation consisting of various spring cereals as regards soil structure and plant health.

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Microdochium majus and Microdochium nivale cause serious disease problems in grasses and cereal crops in the temperate regions. Both fungi can infect the plants during winter (causing pink snow mould) as well as under cool humid conditions during spring and fall. We conducted a pathogenicity test of 15 M. nivale isolates and two M. majus isolates from Norway at low temperature on four different grass cultivars of Lolium perenne and Festulolium hybrids. Significant differences between M. nivale isolates in the ability to cause pink snow mould were detected. The M. nivale strains originally isolated from grasses were more pathogenic than isolates from cereals. The genetic diversity of M. nivale and M. majus isolates was studied by sequencing four genetic regions; Elongation factor-1 alpha (EF-1α), β-tubulin, RNA polymerase II (RPB2) and the Internal Transcribed Spacer (ITS). Phylogenetic trees based on the sequences of these four genetic regions resolved M. nivale and M. majus isolates into separate clades. Higher genetic diversity was found among M. nivale isolates than among M. majus isolates. M. nivale isolates revealed genetic differences related to different host plants (grasses vs. cereals) and different geographic regions (Norway and UK vs. North America). Sequence results from the RPB2 and β-tubulin genes were more informative than those from ITS and EF-1α. The genetic and phenotypic differences detected between Norwegian M. nivale isolates from cereals and grasses support the assumption that host specialization exist within M. nivale isolates.

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Since Emaraviruses have been discovered in 2007 several new species were detected in a range of host plants. Five genome segments of a novel Emaravirus from mosaic‐diseased Eurasian aspen (Populus tremula) have been completely determined. The monocistronic, segmented ssRNA genome of the virus shows a genome organisation typical for Emaraviruses encoding the viral RNA‐dependent RNA polymerase (RdRP, 268.2 kDa) on RNA1 (7.1 kb), a glycoprotein precursor (GPP, 73.5 kDa) on RNA2 (2.3 kb), the viral nucleocapsid protein (N, 35.6 kDa) on RNA3 (1.6 kb), and a putative movement protein (MP, 41.0 kDa) on RNA4 (1.6 kb). The fifth identified genome segment (RNA5, 1.3 kb) encodes a protein of unknown function (P28, 28.1 kDa). We discovered that it is distantly related to proteins encoded by Emaraviruses, such as P4 of European mountain ash ringspot‐associated virus. All proteins from this group contain a central hydrophobic region with a conserved secondary structure and a hydrophobic amino acid stretch, bordered by two highly conserved positions, thus clearly representing a new group of homologues of Emaraviruses. The virus identified in Eurasian aspen is closely associated with observed leaf symptoms, such as mottle, yellow blotching, variegation and chloroses along veins. All five viral RNAs were regularly detectable by RT‐PCR in mosaic‐diseased P. tremula in Norway, Finland and Sweden (Fennoscandia). Observed symptoms and testing of mosaic‐diseased Eurasian aspen by virus‐specific RT‐PCR targeting RNA3 and RNA4 confirmed a wide geographic distribution of the virus in Fennoscandia. We could demonstrate that the mosaic‐disease is graft‐transmissible and confirmed that the virus is the causal agent by detection in symptomatic, graft‐inoculated seedlings used as rootstocks as well as in the virus‐infected scions used for graft‐inoculation. Owing to these characteristics, the virus represents a novel species within the genus Emaravirus and was tentatively denominated aspen mosaic‐associated virus.

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Across the northern hemisphere, six species of aspen (Populus spp.) play a disproportionately important role in promoting biodiversity, sequestering carbon, limiting forest disturbances, and providing other ecosystem services. These species are illustrative of efforts to move beyond single-species conservation because they facilitate hundreds of plants and animals worldwide. This review is intended to place aspen in a global conservation context by focusing on the many scientific advances taking place in such biologically diverse systems. In this manner, aspen may serve as a model for other widespread keystone systems where science-based practice may have world implications for biodiversity conservation. In many regions, aspen can maintain canopy dominance for decades to centuries as the sole major broadleaf trees in forested landscapes otherwise dominated by conifers. Aspen ecosystems are valued for many reasons, but here we highlight their potential as key contributors to regional and global biodiversity. We present global trends in research priorities, strengths, and weaknesses based on, 1) a qualitative survey, 2) a systematic literature analysis, and 3) regional syntheses of leading research topics. These regional syntheses explore important aspen uses, threats, and research priorities with the ultimate intent of research sharing focused on sound conservation practice. In all regions, we found that aspen enhance biodiversity, facilitate rapid (re)colonization in natural and damaged settings (e.g., abandoned mines), and provide adaptability in changing environments. Common threats to aspen ecosystems in many, but not all, regions include effects of herbivory, land clearing, logging practices favoring conifer species, and projected climate warming. We also highlight regional research gaps that emerged from the three survey approaches above. We believe multi-scale research is needed that examines disturbance processes in the context of dynamic climates where ecological, physiological, and genetic variability will ultimately determine widespread aspen sustainability. Based on this global review of aspen research, we argue for the advancement of the “mega-conservation” strategy, centered on the idea of sustaining a set of common keystone communities (aspen) that support wide arrays of obligate species. This approach contrasts with conventional preservation which focuses limited resources on individual species residing in narrow niches.

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In this study, aqueous extracts of Calliandra haematocephala Hassk. leaves and inforescences were tested on seeds of quinoa (Chenopodium album L.) and rice (Oryza sativa L.), and on some of the most noxious-associated weeds, Chenopodium album L. and Holcus lanatus L. in quinoa, and Echinochloa crus-galli (L.) P. Beauv., Echinochloa colona L., Eclipta prostrata L. and Rottboellia cochinchinensis (Lou.) W.D. Clayton in rice. The objectives were to identify extract concentrations at which 50 and 90% of germination (GR[50,90] ) and radicle elongation (RR[50,90] ) were inhibited, to fractionate inforescence extracts for facilitating identifying the chemical group causing allelopathic efects, and to evaluate the fraction showing the stronger weed suppression efects and the least crop damage. Increasing extract concentration rates (0, 6.25, 12.5, 25, 50 and 100% crude extract) were applied to seeds of target crops and weeds. Flower extracts at rates < 0.30 produced GR[50] and RR[50] on H. lanatus, and GR[90] and RR[90] in C. album, while quinoa seeds were not afected. Rice and its target weeds were minimally afected by fower extracts, whereas radicle elongation of all species was signifcantly reduced. A concentration rate > 0.52 caused the RR[50] on rice and all its target weeds. Fractions were quantitatively and qualitatively analysed to detect phytochemical groups, using specifc chemical reagents and thin-layer chromatography (TLC). The fraction F3 from aqueous fower extract showed a high content of favonoids, assumed as the potential allelochemical substance. Total favonoid content in F3 was quantifed as 2.7 mg of quercetin per g F3, i.e., 12.8 mg of quercetin per g of inforescence material. Additionally, feld equivalent extract rates obtained from the harvested fresh inforescence biomass could be determined. These rates ranged between 90 and 143 mL l −1 of F3 aqueous fraction, while for ethanol F3 were 131 mL l −1. Our results are encouraging for fnding sustainable and ecologically friendly alternatives for weed management in crops of high nutritional value, contributing also to counteract the growing problem of herbicide resistance.

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There has been much recent research interest in the existence of a major axis of life‐history variation along a fast–slow continuum within almost all major taxonomic groups. Eco‐evolutionary models of density‐dependent selection provide a general explanation for such observations of interspecific variation in the "pace of life." One issue, however, is that some large‐bodied long‐lived “slow” species (e.g., trees and large fish) often show an explosive “fast” type of reproduction with many small offspring, and species with “fast” adult life stages can have comparatively “slow” offspring life stages (e.g., mayflies). We attempt to explain such life‐history evolution using the same eco‐evolutionary modeling approach but with two life stages, separating adult reproductive strategies from offspring survival strategies. When the population dynamics in the two life stages are closely linked and affect each other, density‐dependent selection occurs in parallel on both reproduction and survival, producing the usual one‐dimensional fast–slow continuum (e.g., houseflies to blue whales). However, strong density dependence at either the adult reproduction or offspring survival life stage creates quasi‐independent population dynamics, allowing fast‐type reproduction alongside slow‐type survival (e.g., trees and large fish), or the perhaps rarer slow‐type reproduction alongside fast‐type survival (e.g., mayflies—short‐lived adults producing few long‐lived offspring). Therefore, most types of species life histories in nature can potentially be explained via the eco‐evolutionary consequences of density‐dependent selection given the possible separation of demographic effects at different life stages.

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Soil particles and bound nutrients that erode from agricultural land may end up in surface waters and cause undesirable changes to the environment. Various measures, among them constructed wetlands have been proposed as mitigation, but their efficiency varies greatly. This work was motivated by the assumption that the induced coagulation of particles may accelerate sedimentation in such wetlands and by that help reduce the amount of material that is lost from the vicinity of the diffuse source. Our specific aim was to laboratory-test the effectiveness of various salt-based coagulants in accelerating the process of sedimentation. We tested the effect of Na+, Mg2+, Ca2+, Fe3+ and Al3+ cations in 10, 20, 40 and 80 mg L-1 doses added to a soil solution in select, soluble forms of their chlorides, sulphates and hydroxides. We mixed such salts with 1 gram of physically dispersed, clay and silt rich (>85% in total) soil material in 500 mL of solution and used time-lapse photography and image analysis to evaluate the progress of sedimentation over 3 hours. We found that 20–40 mg L-1 doses of Mg2+, Ca2+ in their chloride or sulphate forms appeared to provide the best consensus in terms of efficiently accelerating sedimentation using environmentally present and acceptable salts but keeping their dosage to a minimum. Comprehensive in-field efficiency and environmental acceptability testing is warranted prior to any practical implementation, as well as an assessment of small scale economic and large-scale environmental benefits by retaining soil and nutrients at/near the farm.

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The categorical and qualitative nature of currently available soil structural data along with the lack of a geographically broad dataset have impeded progress in understanding the development of soil structure. In this study, we assembled a soil, climate, and ecological dataset for the USA, and used it to analyze relationships between soil structure (ped type, shape, size, and grade) and exogenous and endogenous variables influencing the development of soil structure. We analyzed a subset of the National Cooperative Soil Survey (NCSS) Soil Characterization database after merging this information with climatological and ecological data. The merged and cleaned dataset contains >4400 observations from approximately 1600 pedons. We found that climate, as an exogenous factor was the most important predictor of ped shape and size. Cold and/or dry climates promoted the development of larger anisotropic peds with rougher surfaces whereas warmer and more humid climates promoted the development of finer equidimensional peds with smoother surfaces. Based on these findings, we argue that climate promotes the development of soil structure along either fragmentation or aggregation pathways. The former pathway is characterized by largely mechanical processes in cold and dry environments, whereas aggregation is promoted by predominately biological and chemical mechanisms found in warmer and wet environments. This connection between climate and the development of soil structure represents a potentially important effect of climate on a morphological property strongly linked to soil hydrology that warrants further investigation with continental-scale soil data.

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Global economic value of agriculture production resulting from animal pollination services has been estimated to be $235–$577 billion. This estimate is based on quantification of crops that are available at the global markets, and mainly originates from countries with precise information about quantities of agriculture production, exports, and imports. In contrast, knowledge about the contribution of pollinators to household food and income in small-scale farming at local and regional scales is still lacking, especially for developing countries where the availability of agricultural statistics is limited. Although the global decline in pollinator diversity and abundance has received much attention, relatively little effort has been directed towards understanding the role of pollinators in small-scale farming systems, which feed a substantial part of the world’s population. Here, we have assessed how local farmers in northern Tanzania depend on insect-pollinated crops for household food and income, and to what extent farmers are aware of the importance of insect pollinators and how they can conserve them. Our results show that local farmers in northern Tanzania derived their food and income from a wide range of crop plants, and that 67% of these crops depend on animal pollination to a moderate to essential degree. We also found that watermelon—for which pollination by insects is essential for yield—on average contributed nearly 25% of household income, and that watermelons were grown by 63% of the farmers. Our findings indicate that local farmers can increase their yields from animal pollinated crops by adopting more pollinator-friendly farming practices. Yet, we found that local farmers’ awareness of pollinators, and the ecosystem service they provide, was extremely low, and intentional actions to conserve or manage them were generally lacking. We therefore urge agriculture authorities in Tanzania to act to ensure that local farmers become aware of insect pollinators and their important role in agriculture production.

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Purpose Biogas residues, digestates, contain valuable nutrients and are therefore suitable as agricultural fertilizers. However, the application of fertilizers, including digestates, can enhance greenhouse gas (GHG) emissions. In this study different processes and post-treatments of digestates were analyzed with respect to triggered GHG emissions in soil. Methods In an incubation experiment, GHG emissions from two contrasting soils (chernozem and sandy soil) were compared after the application of digestate products sampled from the process chain of a food waste biogas plant: raw substrate, digestate (with and without bentonite addition), digestates after separation of liquid and solid phase and composted solid digestate. In addition, the solid digestate was sampled at another plant. Results The plant, where the solid digestate originated from, and the soil type influenced nitrous oxide (N2O) emissions significantly over the 38-day experiment. Composting lowered N2O emissions after soil application, whereas bentonite addition did not have a significant effect. High peaks of N2O emissions were observed during the first days after application of acidified, liquid fraction of digestate. N2O emissions were strongly correlated to initial ammonium (NH4+) content. Conclusion Fertilization with dewatered digestate (both fractions) increased N2O emission, especially when applied to soils high in nutrients and organic matter.

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Couch grass (Elymus repens) is a morphologically diverse, rhizomatous, perennial grass that is a problematic weed in a wide range of crops. It is generally controlled by glyphosate or intensive tillage in the intercrop period, or selective herbicides in non-susceptible crops. The aim of this review is to determine the efficacy of non-chemical strategies for E. repens control. The review shows that indirect control measures like crop choice, subsidiary crops, and fertilizer regimes influence E. repens abundance, but usually cannot control E. repens. Defoliation (e.g., mowing) can control E. repens growth, but efficacy varies between clones, seasons, and defoliation frequencies. Tillage in the intercrop period is still the main direct non-chemical control method for E. repens and its efficacy can be increased, and negative side-effects minimized by an appropriate tillage strategy. Some new tillage implements are on the market (Kvik-up type machines) or under development (root/rhizome cutters). Alternative methods that can kill E. repens rhizomes (e.g., steaming, soil solarization, biofumigation, hot water, flooding) often have high costs or time requirements. More studies on the effect of cropping system approaches on E. repens and other perennial weeds are needed.

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Allelopathic potential of 10 teff varieties was assessed in laboratory experimentation (conducted in NIBIO, Norway), and determined with an agar-based bioassay using ryegrass and radish as model weeds. Field experiments were conducted in Tigray, Ethiopia during 2015 and 2016 to identify the most important agronomic traits of teff contributing to its weed competitive ability. A split plot design with three blocks was used considering hand weeding as the main plot and varieties as the subplot. Randomized complete block design (RCBD) with four blocks was used in the laboratory experiment. The highest potential allelopathic activity (PAA) and specific potential allelopathic activity (SPAA) were recorded from a local landrace with an average PAA value of 11.77% and SPAA value of 1.21%/mg respectively, when ryegrass was used as the model weed. ‘Boset’ had the highest average PAA value of 16.25% and an SPAA value of 1.53%/mg, when using radish as the model weed. The lowest PAA and SPAA values were recorded from ‘DZ-Cr-3870 when using ryegrass and radish as model weeds. Days to emergence, height, tiller no./plant, biomass yield, and PAA of the crop significantly contributed to the variance of the weed biomass, cover, and density. Hence, they were the most important agronomic traits enhancing the competitive ability of teff.

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Teff is a staple and well adapted crop in Ethiopia. Weed competition and control have major effects on yields and economic returns of the crop in the country. Among the weed management methods, development and use of weed competitive teff varieties remain the cheapest and most sustainable weed management option. Ten teff varieties were tested for their weed competitive ability in two locations. Treatments were applied using a split plot design with three blocks at each location for two consecutive seasons. Hand weeding and non-weeded treatments were applied to whole plot treatments with teff varieties assigned as split plots within the whole plot. The main objective was to determine relative competitive ability among teff varieties. Results showed that teff varieties showed significant variation in their weed competitive abilities. The varieties ‘Kora’ and ‘DZ-Cr-387’ significantly reduced weed density, dry weight, and cover more than the other teff varieties. They also had the lowest yield losses with a loss of 6% in biomass yield and 18% in grain yield recorded from ‘Kora’ and a loss of 17% in biomass yield and 21% in grain yield recorded from ‘DZ-Cr-387’. Therefore, they showed the highest weed competitive ability compared to the other varieties.

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The current study provides an in vivo analysis of the production of reactive oxygen species (ROS) and oxidative stress in the nematode Caenorhabditis elegans following exposure to EU reference silver nanoparticles NM300K and AgNO3. Induction of antioxidant defenses was measured through the application of a SOD-1 reporter, and the HyPer and GRX biosensor strains to monitor changes in the cellular redox state. Both forms of Ag resulted in an increase in sod-1 expression, elevated H2O2 levels and an imbalance in the cellular GSSG/GSH redox status. Microscopy analysis of the strains revealed that AgNO3 induced ROS-related effects in multiple tissues, including the pharynx, intestinal cells and muscle tissues. In contrast, NM300K resulted in localized ROS production and oxidative stress, specifically in tissues surrounding the intestinal lumen. This indicates that Ag from AgNO3 exposure was readily transported across the whole body, while Ag or ROS from NM300K exposure was predominantly confined within the luminal tissues. Concentrations resulting in an increase in ROS production and changes in GSSG/GSH ratio were in line with the levels associated with observed physiological toxic effects. However, sod-1 was not induced at the lowest Ag concentrations, although reprotoxicity was seen at these levels. While both forms of Ag caused oxidative stress, impaired development, and reprotoxicity, the results suggest different involvement of ROS production to the toxic effects of AgNO3 versus NM300K.

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We fertilized a Norway spruce (Picea abies (L.) Karst.) stand on rich mineral soil with 3 t ha−1 of wood ash (ASH), 150 kg ha−1 of nitrogen (N) or a combination of wood ash and nitrogen (ASH + N), in addition to unfertilized control plots. After five growing seasons, we remeasured the trees and took core samples. Current- and previousyear needles were sampled and analyzed for total nitrogen and carbon, low-molecular weight phenolics and condensed tannins. Annual volume increment and standing volume were significantly higher in the ASH + N treatment than in control plots after 5 years. N gave a significant positive effect on basal area growth in the third year, after which the effect diminished. The ASH + N treated trees, on the other hand, showed an increasing basal area growth trend throughout the period. ASH reduced the total concentration of low-molecular weight phenolic compounds significantly in current-year needles. Phenolic acids increased under both ASH and ASH + N, while flavonoids decreased significantly under the same treatments compared to N. By including annual growth rate before fertilization in the analyses, the effect of N-treatment on flavonoids was positive only in trees with higher growth rates, and in those trees the concentration was higher than in both ASH-treated plots and controls. An acetophenone, constituting more than half of the total low-molecular weight phenolics concentration, was strongly reduced under all fertilization treatments. These results demonstrate that in addition to effects on tree growth, fertilization of the forest floor also has a strong influence on other metabolic processes of trees, with potential implications for ecosystem functioning.

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The blackwater stream of domestic wastewater contains energy and the majority of nutrients that can contribute to a circular economy. Hygienically safe and odor-free nutrient solution produced from anaerobically treated source-separated blackwater through an integrated post-treatment unit can be used as a source of liquid fertilizer. However, the high water content in the liquid fertilizer represents a storage or transportation challenge when utilized on agricultural areas, which are often situated far from the urban areas. Integration of microalgae into treated source-separated blackwater (BW) has been shown to effectively assimilate and recover phosphorus (P) and nitrogen (N) in the form of green biomass to be used as slow release biofertilizer and hence close the nutrient loop. With this objective, a lab-scale flat panel photobioreactor was used to cultivate Chlorella sorokiniana strain NIVA CHL 176 in a chemostat mode of operation. The growth of C. sorokiniana on treated source-separated blackwater as a substrate was monitored by measuring dry biomass concentration at a dilution rate of 1.38 d−1, temperature of 37 °C and pH of 7. The results indicate that the N and P recovery rates of C. sorokiniana were 99 mg N L−1d−1 and 8 mg P L−1d−1 for 10% treated BW and reached 213 mg N L−1d−1 and 35 mg P L−1d−1, respectively when using 20% treated BW as a substrate. The corresponding biomass yield on light, N and P on the 20% treated BW substrate were 0.37 g (mol photon)−1, 9.1 g g−1 and 54.1 g g−1, respectively, and up to 99% of N and P were removed from the blackwater.

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Although it is well known that insects are sensitive to temperature, how they will be affected by ongoing global warming remains uncertain because these responses are multifaceted and ecologically complex. We reviewed the effects of climate warming on 31 globally important phytophagous (plant‐eating) insect pests to determine whether general trends in their responses to warming were detectable. We included four response categories (range expansion, life history, population dynamics, and trophic interactions) in this assessment. For the majority of these species, we identified at least one response to warming that affects the severity of the threat they pose as pests. Among these insect species, 41% showed responses expected to lead to increased pest damage, whereas only 4% exhibited responses consistent with reduced effects; notably, most of these species (55%) demonstrated mixed responses. This means that the severity of a given insect pest may both increase and decrease with ongoing climate warming. Overall, our analysis indicated that anticipating the effects of climate warming on phytophagous insect pests is far from straightforward. Rather, efforts to mitigate the undesirable effects of warming on insect pests must include a better understanding of how individual species will respond, and the complex ecological mechanisms underlying their responses.

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Protected Areas (PAs) in Tanzania had been established originally for the goal of habitat, landscape and biodiversity conservation. However, human activities such as agricultural expansion and wood harvesting pose challenges to the conservation objectives. We monitored a decade of deforestation within 708 PAs and their unprotected buffer areas, analyzed deforestation by PA management regimes, and assessed connectivity among PAs. Data came from a Landsat based wall-to-wall forest to non-forest change map for the period 2002–2013, developed for the definition of Tanzania’s National Forest Reference Emissions Level (FREL). Deforestation data were extracted in a series of concentric bands that allow pairwise comparison and correlation analysis between the inside of PAs and the external buffer areas. Half of the PAs exhibit either no deforestation or significantly less deforestation than the unprotected buffer areas. A small proportion (10%; n = 71) are responsible for more than 90% of the total deforestation; but these few PAs represent more than 75% of the total area under protection. While about half of the PAs are connected to one or more other PAs, the remaining half, most of which are Forest Reserves, are isolated. Furthermore, deforestation inside isolated PAs is significantly correlated with deforestation in the unprotected buffer areas, suggesting pressure from land use outside PAs. Management regimes varied in reducing deforestation inside PA territories, but differences in protection status within a management regime are also large. Deforestation as percentages of land area and forested areas of PAs was largest for Forest Reserves and Game Controlled areas, while most National Parks, Nature Reserves and Forest Plantations generally retained large proportions of their forest cover. Areas of immediate management concern include the few PAs with a disproportionately large contribution to the total deforestation, and the sizeable number of PAs being isolated. Future protection should account for landscapes outside protected areas, engage local communities and establish new PAs or corridors such as village-managed forest areas.

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The lumpfish Cyclopterus lumpus is commercially exploited in numerous areas of its range in the North Atlantic Ocean, and is important in salmonid aquaculture as a biological agent for controlling sea lice. Despite the economic importance, few genetic resources for downstream applications, such as linkage mapping, parentage analysis, marker-assisted selection (MAS), quantitative trait loci (QTL) analysis, and assessing adaptive genetic diversity are currently available for the species. Here, we identify both genome- and transcriptome-derived microsatellites loci from C. lumpus to facilitate such applications. Across 2,346 genomic contigs, we detected a total of 3,067 microsatellite loci, of which 723 were the most suitable ones for primer design. From 116,555 transcriptomic unigenes, we identified a total of 231,556 microsatellite loci, which may indicate a high coverage of the available STRs. Out of these, primer pairs could only be designed for 6,203 loci. Dinucleotide repeats accounted for 89 percent and 52 percent of the genome- and transcriptome-derived microsatellites, respectively. The genetic composition of the dominant repeat motif types showed differences from other investigated fish species. In the genome-derived microsatellites AC/GT (67.8 percent), followed by AG/CT (15.1 percent) and AT/AT (5.6 percent) were the major motifs. Transcriptome-derived microsatellites showed also most dominantly the AC/GT repeat motif (33 percent), followed by A/T (26.6 percent) and AG/CT (11 percent). Functional annotation of microsatellite-containing transcriptomic sequences showed that the majority of the expressed sequence tags encode proteins involved in cellular and metabolic processes, binding activity and catalytic reactions. Importantly, STRs linked to genes involved in immune system process, growth, locomotion and reproduction were discovered in the present study. The extensive genomic marker information reported here will facilitate molecular ecology studies, conservation initiatives and will benefit many aspects of the breeding programmes of C. lumpus.

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In studies of consumption of local food specialties (LFSs), individual personalities are rarely mentioned. In this article, we want to expand on and provide a nuanced explanation of the characteristics of these consumers of these products, asking: Are there any personality traits that characterize these consumers? We use the Big Five personality model to unpack the relationship between individuals' personalities and choices of LFS in the Norwegian context. The model consists of the following five personal traits: extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience. These personality traits are latent, but through questions regarding behavior, the traits may be revealed. To construct latent variables to measure these traits, we apply the graded response model. Furthermore, socioeconomic variables are combined with personality traits in logistic regression models to find the relationships between personality and choice of Norwegian LFSs. Our results show that in all models the latent variable Openness to experience was one of the most important predictors of all the choices of LFS made by individuals. Openness to experience is characterized by fantasy, aesthetic sensitivity, attentiveness to inner feelings, preference for variety, and intellectual curiosity. The consequence of the connection between Openness to experience and LFS is that stakeholders may take this into account when seeking to increase sales.

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A transition to a bioeconomy implies an increased focus on efficient and sustainable use of biological resources. A common, but often neglected feature of these resources is their location dependence. To optimize their use, for example in bioeconomic industrial clusters, this spatial aspect should be integrated in analyses. Optimal design and localization of a bioeconomic cluster with respect to the various biological and non-biological resources required for the cluster, the composition of industrial facilities in the cluster, as well as the demands of the outputs of the cluster, is crucial for profitability and sustainability. We suggest that optimal design and location of bioeconomic clusters can benefit from the use of a Multicriteria Decision Analysis (MCDA) in combination with Geographic Information Systems (GIS) and Operations Research modeling. The integration of MCDA and GIS determines a set of candidate locations based on various criteria, including resource availability, accessibility, and usability. A quantitative analysis of the flow of resources between and within the different industries is then conducted based on economic Input-Output analysis. Then, the cluster locations with the highest potential profit, and their composition of industrial facilities, are identified in an optimization model. A case study on forest-based bioeconomic clusters in the Østfold county of Norway is presented to exemplify this methodology, the expectation being that further implementation of the method at the national level could help decision makers in the planning of a smoother transition from a fossil-based economy to a bioeconomy.

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Young forest stands and clearcuts in the boreal forest created by modern forestry practices along with meadows of abandoned summer farms may contribute as feeding areas for beef cattle. The patchy distribution and varying quality and diversity of forage on such unimproved lands may affect cattle productivity. Weight gain of 336 beef cows and 270 calves free-ranging during three summer grazing seasons was monitored in boreal forests of southeastern Norway, stocked at either high (0.16 cows ha-1) and low (0.04 cows ha-1) stocking densities. We used linear mixed effect models for assessing intrinsic correlates of weight gain in cows and calves in the two areas. Habitat use and home range size of a subsample of 53 cows were monitored by using GPS collars programmed to log locations at 5 min. intervals during the grazing season. Additional extrinsic correlates of weight gain for the subsampled cows using a linear mixed model were also tested. Average weight gain of beef cows grazing at the low stocking density was positive among cows of early maturing breeds (represented by Hereford) gaining 24 ± 2.8 kg ( ± SE), while cows of late maturing breeds (mainly represented by Charolais) had an average weight loss of 9 ± 8.4 kg. The average weight gain was negative for beef cows of both early (Herefords) and late maturing breeds (mainly represented by Charolais but also Limousin and Simmental) at the high stocking density. Within both breed groups, there was a negative relationship between breed-specific average weight of cows at turnout and weight gain during the grazing period, while a prolonged grazing period was slightly positively related to weight gain. There was no relationship between weight gain and home range size and proportion of grazing habitat for the 53 cows fitted with GPS collars. Higher weight gains in calves of the low compared to the high stocking density area was found. However, there was no breed effect of weight gain in calves. Across study areas, spring-born suckler calves gained more weight than autumn-born calves (92 ± 1.7 kg vs. 65 ± 4.4 kg). Also, there were higher weight gains for springborn bull-calves than spring-born heifers (100 ± 2.4 kg vs. 94 ± 2.2 kg). Overall, the results indicate that it is possible to achieve acceptable weight gains for cattle grazing coniferous forest by finding breeds suitable for these extensive areas and stocking at moderate densities.

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Soil respiration is an important ecosystem process that releases carbon dioxide into the atmosphere. While soil respiration can be measured continuously at high temporal resolutions, gaps in the dataset are inevitable, leading to uncertainties in carbon budget estimations. Therefore, robust methods used to fill the gaps are needed. The process-based non-linear least squares (NLS) regression is the most widely used gap-filling method, which utilizes the established relationship between the soil respiration and temperature. In addition to NLS, we also implemented three other methods based on: 1) artificial neural networks (ANN), driven by temperature and moisture measurements, 2) singular spectrum analysis (SSA), relying only on the time series itself, and 3) the expectation-maximization (EM) approach, referencing to parallel flux measurements in the spatial vicinity. Six soil respiration datasets (2017–2019) from two boreal forests were used for benchmarking. Artificial gaps were randomly introduced into the datasets and then filled using the four methods. The time-series-based methods, SSA and EM, showed higher accuracies than NLS and ANN in small gaps (<1 day). In larger gaps (15 days), the performance was similar among NLS, SSA and EM; however, ANN showed large errors in gaps that coincided with precipitation events. Compared to the observations, gap-filled data by SSA showed similar degree of variances and those filled by EM were associated with similar first-order autocorrelation coefficients. In contrast, data filled by both NLS and ANN exhibited lower variance and higher autocorrelation than the observations. For estimations of the annual soil respiration budget, NLS, SSA and EM resulted in errors between −3.7% and 5.8% given the budgets ranged from 463 to 1152 g C m−2 year−1, while ANN exhibited larger errors from −11.3 to 16.0%. Our study highlights the two time-series-based methods which showed great potential in gap-filling carbon flux data, especially when environmental variables are unavailable.

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The abstract classification system Nature in Norway (NiN) has detailed ecological definitions of a high number of ecosystem units, but its applicability in practical vegetation mapping is unknown because it was not designed with a specific mapping method in mind. To investigate this further, two methods for mapping – 3D aerial photographic interpretation of colour infrared photos and field survey – were used to map comparable neighbouring sites of 1 km2 in Hvaler Municipality, south-eastern Norway. The classification accuracy of each method was evaluated using a consensus classification of 160 randomly distributed plots within the study sites. The results showed an overall classification accuracy of 62.5% for 3D aerial photographic interpretation and 82.5% for field survey. However, the accuracy varied for the ecosystem units mapped. The classification accuracy of ecosystem units in acidic, dry and open terrain was similar for both methods, whereas classification accuracy of calcareous units was highest using field survey. The mapping progress using 3D aerial photographic interpretation was more than two times faster than that of field survey. Based on the results, the authors recommend a method combining 3D aerial photographic interpretation and field survey to achieve effectively accurate mapping in practical applications of the NiN system.

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This study aims to understand the environmental factors, focusing on rain and fungal infection, affecting the assembly of glutenin polymers during grain maturation. Spring wheat was grown in the field and grains were sampled from 50% grain moisture until maturity. Grain moisture content, protein content, size of glutenin polymers, the presence of proteases, and the amount of DNA from common wheat pathogenic fungi were analysed. Rain influenced the rate of grain desiccation that occurred parallel to the rate of glutenin polymer assembly. Rapid desiccation contributed to faster glutenin polymer assembly than gradual desiccation. Severe reduction in the glutenin polymer size coincided with increased grain moisture due to rain. Furthermore, increased fungal DNA followed by presence of gluten-degrading proteases was observed in the grain after humid conditions. The presence of gluten-degrading proteases was presumably involved in reducing the size of glutenin polymers in grain. Our study gave new insight into how environmental conditions could be associated with the assembly of glutenin polymers during grain maturation. The results suggest that rain and/or fungal proteases play an important role in reducing the molecular size of glutenin polymers.

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Field trapping experiments were carried out in Norway to measure attraction of the cherry bark tortrix (CBT) Enarmonia formosana to volatile blends of candidate compounds including acetic acid (AA), linalool oxide pyranoid (LOXP), 2-phenylethanol (PET), pear ester (E,Z)2,4-ethyl decadienoate (PE) and (E)-β-farnesene (BF). The binary blend of AA and LOXP caught the highest number of CBT adults. While addition of PET along with PE did not significantly change the attraction, a sex-dependent decrease of female captures was found when LOXP was replaced by PET/PE. Male attraction to AA/LOXP did not differ when PET/PE were added to the blend or when LOXP was substituted by the same two compounds. A similar attraction to blank traps was recorded for the ternary blend of LOXP/PET/PE, for the binary blend of PET/PE and for LOXP alone, supporting AA as a possible fundamental component of CBT kairomone. In addition, a lower number of bycatches of Hedya nubiferana, Anthophila fabriciana, Synanthedon myopaeformis, Pammene spp. and Pandemis spp. were scored in the AA/LOXP than in any blend including AA/PET/PE. BF was not behaviourally active on CBT in our field experiments. The high attraction of both sexes of CBT to the binary blend of AA/LOXP represents a first step towards the identification of a multicomponent kairomone for this pest. A continuous flight activity of both sexes of CBT was recorded from the end of May until the beginning of August, supporting the hypothesis that CBT is univoltine in Norway. Because larval infestation on tree trunks varies substantially with apple varieties, we encourage the collection of additional data to attempt a correlation between adult catch by AA/LOXP traps and the following larval population.

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The main objective of this paper is to present the new model BASGRA_N, to show how it was parameterized for grass swards in Scandinavia, and to evaluate its performance in predicting above-ground biomass, crude protein, cell wall content and dry matter digestibility. The model was developed to allow simulation of: (1) the impact of N-supply on the plants and their environment, (2) the dynamics of greenhouse gas emissions from grasslands, (3) the dynamics of cell-wall content and digestibility of leaves and stems, which could not be simulated with its predecessor, the BASGRA-model. To calibrate and test the model, we used field experimental data. One dataset included observations of biomass (DM) and crude protein content (CP) under different N fertilizer regimes from five sites in central and southern Sweden. The other dataset included observations of DM, and sward components as well as CP, cell wall content (NDF) and DM digestibility as affected by harvesting regime from one site in southwestern Norway. The total number of experiments was nine, of which three were used for model testing. When BASGRA_N was run with the maximum a-posteriori (MAP) parameter vector from the Bayesian calibration for the Swedish test sites, DM and CP were both simulated to an overall Pearson correlation coefficient (Rb) of minimum 0.58, Willmott's index of agreement (d) of minimum 0.69 and normalized root mean squared error (NRMSE) of maximum 0.30. Corresponding metrics for Norwegian test sites were 0.93, 0.96 and 0.27 for DM and > 0.73, > 0.61, < 0.18 for DM digestibility, NDF and CP content, respectively. We conclude that BASGRA_N can be used to simulate yield and CP responses to N with satisfactory precision, while maintaining key features from its predecessor. The results also suggest that DM digestibility and NDF can be simulated satisfactorily, which is supported by results from a recent model comparison study. Further testing of the model is needed for a few variables for which we currently do not have enough data, notably leaching and emission of N-containing compounds. Further work will include application of the model to investigate greenhouse gas mitigation options, and evaluation against independent data for the conditions for which it will be applied.

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Horse owners may lack knowledge about natural thermoregulation mechanisms in horses. Horses are managed intensively; usually stabled at night and turned out during the day. Some are clipped and many wear a blanket, practices which reduce the horse's ability to regulate heat dissipation. The aim of this study was to investigate the relationship between hair coat characteristics, body condition and infrared surface temperatures from different body parts of horses. Under standard conditions, the body surface temperature of 21 adult horses were investigated using infrared thermography. From several readings on the same body part, a mean temperature was calculated for each body part per horse. Detailed information on horse breed, age, management and body condition was collected. Hair coat samples were also taken for analyses. A mixed statistical model was applied. Warmblood horse types (WB) had lower hair coat sample weights and shorter hair length than coldblood horse types (CB). The highest radiant surface temperatures were found at the chest 22.5 ± 0.9 °C and shoulders 20.4 ± 1.1 °C and WB horses had significantly higher surface temperatures than CB horses on the rump (P < 0.05). Horses with a higher hair coat sample weight had a lower surface temperature (P < 0.001) and hind hooves with iron shoes had a significant lower surface temperature than unshod hind hooves (P = 0.03). In conclusion, individual assessment of radiant surface temperature using infrared thermography might be a promising tool to gather data on heat loss from the horses' body. Such data may be important for management advice, as the results showed individual differences in hair coat characteristics and body condition in horses of similar breeds.

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The aim of the present work was to investigate the potential of Porphyra sp. as an alternative source of protein to soybean meal in diets for sheep. Our experimental treatments included a control diet (CON) based on grass silage and crushed oats and three diets containing protein supplements, clover silage (CLO), soybean meal (SOY) or Porphyra sp. (POR) to increase dietary crude protein concentrations. We studied its effects on rumen fermentation, growth rate and methane emissions. Ruminal fermentation characteristics, kinetics of gas production and methane production were studied in vitro by using batch cultures inoculated with rumen inoculum from sheep. There were no differences among diets in total volatile fatty acids (VFA) production or in the VFA profile in vitro. Across treatments, we measured no differences in methane production either in vitro or in vivo, and we saw no noticeable antimethanogenic effect of Porphyra sp. The present in vivo trial with lambs showed no differences in average daily weight gain when fed diets including Porphyra sp. or soybean meal diets (250 and 254 g/d, respectively). We conclude that Porphyra sp. has a protein value similar to high-quality protein sources like soybean meal.

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To support decision-makers considering adopting integrated pest management (IPM) cropping in Norway, we used stochastic efficiency analysis to compare the risk efficiency of IPM cropping and conventional cropping, using data from a long-term field experiment in southeastern Norway, along with data on recent prices, costs, and subsidies. Initial results were not definitive, so we applied stochastic efficiency with respect to a function, limiting the assumed risk aversion of farmers to a plausible range. We found that, for farmers who are risk-indifferent to moderately (hardly) risk averse, the conventional system was, compared to IPM, less (equally) preferred.

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This study provides a multi-attribute approach to support decisions by Norwegian crop farmers considering adopting innovative crop protection measures. In modelling choice among pest management strategies, we have accounted for both economic risks, risks to human health and risks to the environment. We used the Simple Multi-Attribute Rating Technique (SMART) to evaluate the results of a field trial comparing four different pest management strategies. In the trial, various pre-crops in year one were followed by two consecutive years of winter wheat. Two treatments had different levels of integrated pest management (IPM). IPM1 was the most innovative treatment and used less pesticides (i.e. herbicides, insecticides and fungicides) than IPM2. The third treatment (‘Worst Case’, WC) used pesticides routinely. The fourth treatment (‘No Plant Protection’, NPP) used no plant protection measures except one reduced dose of herbicide per year on winter wheat. Two main attributes were included in the SMART analysis, an economic indicator and a pesticide load indicator, each of which comprised a number of attributes at a subsidiary level. The results showed that the IPM1 and NPP strategies performed better than IPM2 and the WC strategies. However, the ranking of the pest management practices depended on the weighting of the two main attributes. Although the SMART analysis gave ordinal utility values, permitting only ranking of the alternatives, we were able to transform the results to measure financial differences between the alternatives.

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From the Middle Ages until the twentieth century, water meadows in Europe were primarily irrigated to improve their productivity and to lengthen the growing season. They were water management systems designed to collect and use water and to discharge it: water had to be kept moving. This chapter presents a general overview and a history of research on European water meadows. It also examines examples from the sandy landscapes of northwestern Europe, from Slovakia, and Norway. Three main types of water meadows are distinguished: simple dam systems, more elaborate catchworks, and highly developed bedworks. Of these, bedworks were technically and organizationally the most complex; they were also the most costly in construction and maintenance. Most water meadows were abandoned in the twentieth century; in many places, however, their traces can still be recognized in the landscape. They are both an interesting part of European agrarian and landscape heritage and a carrier of regional identity. In recent years, a number of water meadows have been restored, for ecological, water management, tourism, and heritage purposes.

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Risk models for decisions on fungicide use based on weather data, disease monitoring, and control thresholds are used as important elements in a sustainable cropping system. The need for control of leaf blotch diseases in wheat (caused by Zymoseptoria tritici, Parastagonospora nodorum and Pyrenophora tritici-repentis) vary significantly across years and locations. Disease development is mainly driven by humidity events during stem elongation and heading. Two risk models were tested in field trials in order to identify situations favourable for the development of leaf blotch diseases in Lithuania, Norway, Sweden, Finland and Denmark. The Crop Protection Online (CPO) model uses days with precipitation (>1 mm), while the humidity model (HM) uses 20 continuous hours with relative humidity (RH) ≥ 85% as criteria for the need of a fungicide application. Forty-seven field trials were carried out during two seasons to validate these two risk-models against reference fungicide treatments. The season 2018 was dry and 2019 had an average precipitation profile. The two risk models with few exceptions provided acceptable disease control. In 2018, very few treatments were recommended by the models, saving 85–98% of treatments compared to the reference treatments, while in the wetter season 2019, 31% fewer applications were recommended. Based on specific criteria including fungicide input and net yield responses the models gave correct recommendations in 95% of the trials in 2018 and in 54–58% of the trials in 2019 compared with reference treatments dominated by 2–3 sprays. In comparison with single spray references, the models gave correct recommendations in 54–69% of the situations.

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Key message A locus on wheat chromosome 2A was found to control feld resistance to both leaf and glume blotch caused by the necrotrophic fungal pathogen Parastagonospora nodorum. Abstract The necrotrophic fungal pathogen Parastagonospora nodorum is the causal agent of Septoria nodorum leaf blotch and glume blotch, which are common wheat (Triticum aestivum L.) diseases in humid and temperate areas. Susceptibility to Septoria nodorum leaf blotch can partly be explained by sensitivity to corresponding P. nodorum necrotrophic efectors (NEs). Susceptibility to glume blotch is also quantitative; however, the underlying genetics have not been studied in detail. Here, we genetically map resistance/susceptibility loci to leaf and glume blotch using an eight-founder wheat multiparent advanced generation intercross population. The population was assessed in six feld trials across two sites and 4 years. Seedling infltration and inoculation assays using three P. nodorum isolates were also carried out, in order to compare quantitative trait loci (QTL) identifed under controlled conditions with those identifed in the feld. Three signifcant feld resistance QTL were identifed on chromosomes 2A and 6A, while four signifcant seedling resistance QTL were detected on chromosomes 2D, 5B and 7D. Among these, QSnb.niab-2A.3 for feld resistance to both leaf blotch and glume blotch was detected in Norway and the UK. Colocation with a QTL for seedling reactions against culture fltrate from a Norwegian P. nodorum isolate indicated the QTL could be caused by a novel NE sensitivity. The consistency of this QTL for leaf blotch at the seedling and adult plant stages and culture fltrate infltration was confrmed by haplotype analysis. However, opposite efects for the leaf blotch and glume blotch reactions suggest that diferent genetic mechanisms may be involved.

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Probiotics confer a health benefit on the host and could be used as a good alternative to antibiotics. Probiotics are strain‐specific when exerting their function, so it is necessary to identify them to strain level. In recent years, intra‐species molecular typing and identification methods have developed rapidly, which commonly are used for typing the main pathogenic bacteria and rare for studies on probiotic typing, whilst it is imperative. This article describes molecular typing methods including AFLP, RAPD, PFGE, ribotyping, MLST, rep‐PCR and whole‐genome sequencing to identity some aquatic probiotics approved by the Ministry of Agriculture of China, which are Bifidobacterium, Enterococcus, Lactobacillus, Pediococcus, Aspergillus, Bacillus, Rhodopseudomonas palustris and Streptococcus thermophilus. In addition, the principles, applications, advantages and disadvantages of these typing methods are also discussed.

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The necrotrophic fungal pathogen Parastagonospora nodorum causes Septoria nodorum blotch (SNB), which is one of the dominating leaf blotch diseases of wheat in Norway. A total of 165 P. nodorum isolates were collected from three wheat growing regions in Norway from 2015 to 2017. These isolates, as well as nine isolates from other countries, were analyzed for genetic variation using 20 simple sequence repeat (SSR) markers. Genetic analysis of the isolate collection indicated that the P. nodorum pathogen population infecting Norwegian spring and winter wheat underwent regular sexual reproduction and exhibited a high level of genetic diversity, with no genetic subdivisions between sampled locations, years or host cultivars. A high frequency of the presence of necrotrophic effector (NE) gene SnToxA was found in Norwegian P. nodorum isolates compared to other parts of Europe, and we hypothesize that the SnToxA gene is the major virulence factor among the three known P. nodorum NE genes (SnToxA, SnTox1, and SnTox3) in the Norwegian pathogen population. While the importance of SNB has declined in much of Europe, Norway has remained as a P. nodorum hotspot, likely due at least in part to local adaptation of the pathogen population to ToxA sensitive Norwegian spring wheat cultivars.

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Cereal grain contaminated by Fusarium mycotoxins is undesirable in food and feed because of the harmful health effects of the mycotoxins in humans and animals. Reduction of mycotoxin content in grain by cleaning and size sorting has mainly been studied in wheat. We investigated whether the removal of small kernels by size sorting could be a method to reduce the content of mycotoxins in oat grain. Samples from 24 Norwegian mycotoxin-contaminated grain lots (14 from 2015 and 10 from 2018) were sorted by a laboratory sieve (sieve size 2.2 mm) into large and small kernel fractions and, in addition to unsorted grain samples, analyzed with LC-MS-MS for quantification of 10 mycotoxins. By removing the small kernel fraction (on average 15% and 21% of the weight of the samples from the two years, respectively), the mean concentrations of HT-2+T-2 toxins were reduced by 56% (from 745 to 328 µg/kg) in the 2015 samples and by 32% (from 178 to 121 µg/kg) in the 2018 samples. Deoxynivalenol (DON) was reduced by 24% (from 191 to 145 µg/kg) in the 2018 samples, and enniatin B (EnnB) by 44% (from 1059 to 594 µg/kg) in the 2015 samples. Despite low levels, our analyses showed a trend towards reduced content of DON, ADON, NIV, EnnA, EnnA1, EnnB1 and BEA after removing the small kernel fraction in samples from 2015. For several of the mycotoxins, the concentrations were considerably higher in the small kernel fraction compared to unsorted grain. Our results demonstrate that the level of mycotoxins in unprocessed oat grain can be reduced by removing small kernels. We assume that our study is the first report on the effect of size sorting on the content of enniatins (Enns), NIV and BEA in oat grains.

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It is commonly known that the pretreatment of complex substrates yields higher biogas production in anaerobic digestion (AD) by improving hydrolysis. However, it is still questioned whether all solubilized fractions after pretreatment can be used for CH4 production during AD. In this study, the relationship between increased solubilization and AD efficiency in response to different pretreatment conditions of lipid-extracted microalgae waste (LEMW) was investigated. The individual pretreatment (acid and ultrasonic) and combined pretreatment were applied to assess the solubilization of LEMW. A biochemical methane potential (BMP) test was subsequently performed to determine the AD efficiency. Combined pretreatment of LEMW (60 min of irradiation + pH 1) showed the highest performance, achieving CH4 production of 1245 ± 28 mL CH4/L with increased solubilization of 50.4%. However, it was found that increased solubilization did not proportionally increase CH4 productivity. The assessment of the origin of produced CH4 through biomass fractionation supports this finding in that the soluble fraction that does not contribute to CH4 production increased at more severe pretreatment conditions.

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During surveys of insect-associated mycobiomes in Norway, Poland, and Russia, isolates with affinity to Graphilbum (Ophiostomatales, Ascomycota) were recovered. In this study, eight known Graphilbum species as well as the newly collected isolates were compared based on morphology and DNA sequence data for four gene regions. The results revealed seven new species, described here as G. acuminatum, G. carpaticum, G. curvidentis, G. furuicola, G. gorcense, G. interstitiale, and G. sexdentatum. In addition to these species, G. crescericum and G. sparsum were commonly found in Norway. All new species were recovered from conifers in association with bark beetles, cerambycid beetles, and weevils and were morphologically similar, predominantly with pesotum-like asexual morphs. Where sexual morphs were present, these were small ascomata with short necks and rodshaped ascospores having hyaline sheaths. The results suggest that Graphilbum species are common members of the Ophiostomatales in conifer ecosystems.

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Bark beetles belonging to the genus Dryocoetes (Coleoptera, Curculionidae, Scolytinae) are known vectors of fungi, such as the pathogenic species Grosmannia dryocoetidis involved in alpine fir (Abies lasiocarpa) mortality. Associations between hardwood-infesting Dryocoetes species and fungi in Europe have received very little research attention. Ectosymbiotic fungi residing in Ceratocystiopsis and Leptographium (Ophiostomatales, Sordariomycetes, Ascomycota) were commonly detected in previous surveys of the Dryocoetes alni-associated mycobiome in Poland. The aim of this study was to accurately identify these isolates and to provide descriptions of the new species. The identification was conducted based on morphology and DNA sequence data for six loci (ITS1-5.8S, ITS2-28S, ACT, CAL, TUB2, and TEF1-α). This revealed two new species, described here as Ceratocystiopsis synnemata sp. nov. and Leptographium alneum sp. nov. The host trees for the new species included Alnus incana and Populus tremula. Ceratocystiopsis synnemata can be distinguished from its closely related species, C. pallidobrunnea, based on conidia morphology and conidiophores that aggregate in loosely arranged synnemata. Leptographium alneum is closely related to Grosmannia crassivaginata and differs from this species in having a larger ascomatal neck, and the presence of larger club-shaped cells.

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Norway spruce (Picea abies) is a widely used Christmas tree species in the Nordic countries. Postharvest needle retention is an important characteristic for Christmas trees and compared to many fir (Abies) species, Norway spruce has poor postharvest needle retention. This trait is one of the most important qualities in choice of natural versus plastic trees. In this study, current year shoots were cut from 30 Norway spruce seedlot sources, including the most widely used Norwegian Christmas tree provenances, and tested to identify genetic variation in postharvest needle retention. Current year shoots were collected from one field in November and December 2018, and from three fields in October, November and December 2019. The current year shoots were displayed indoors under controlled conditions and allowed to dry. Differences in postharvest needle retention were seen between seedlots, harvesting dates and locations. Our study indicates possibilities of selecting for improved postharvest needle retention in Norway spruce seed sources. Furthermore, postharvest needle retention should be considered as one characteristic to add in the ongoing Norway spruce Christmas tree breeding program.

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Identification of stocktype attributes that speed up field establishment has potential to reduce rotation time of Christmas tree productions. Such morphological and physiological attributes can be targeted in the nursery production. This study tested the effects of container type and nursery seedling density on stocktype attributes at planting and the effects of these on field performance over two years in Abies lasiocarpa and A. nordmanniana Christmas tree stock. Nursery conditions had a considerable impact on seedling attributes at planting. Although sets of these correlated stocktype attributes contributed to forecast field performance, the predictive power was low. No simple relationships were found between plant biomass, stem diameter or height at planting and biomass at final harvest in either of the two species under the range of stocktype variation and field conditions tested. Contrary, stem diameter and stem height at planting explained some of the responses in stem diameter and height after two years in the field. Thus, any target seedling approach would have to be based on a combined set of stocktype attributes exploring more productive stocktypes. The differences observed between stocktypes were largely due to size differences and ontogenetic drift, and stocktypes converged towards a similar field phenotype over time.

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A large area of Estonian hemiboreal forest is recovering from clear-cut harvesting and changing carbon (C) balance of the stands. However, there is a lack of information about C- source/sink relationships during recovery of such stands. The eddy covariance technique was used to estimate C-status through net ecosystem exchange (NEE) of CO2 in two stands of different development stages located in southeast Estonia in 2014. Measured summertime (June–September) mean CO2 concentration was 337.75 ppm with mean NEE −1.72 µmol m−2 s−1. June NEE was −4.60 µmol m−2 s−1; July, August, and September NEE was −1.17, −0.77, and −0.25 µmol m−2 s−1, respectively. The two stands had similar patterns of CO2 exchange; measurement period temperature drove NEE. Our results show that after clear-cutting a 6-year-old forest ecosystem was a light C-sink and 8-year-old young stand demonstrated a stronger C-sink status during the measurement period.

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Endogenous antimicrobial peptides (AMPs) are evolutionarily ancient factors of innate immunity, which are produced by all multicellular organisms and play a key role in their protection against infection. Red king crab (Paralithodes camtschaticus), also called Kamchatka crab, is widely distributed and the best known species of all king crabs belonging to the family Lithodidae. Despite their economic importance, the genetic resources of king crabs are scarcely known and no fullgenome sequences are available to date. Therefore, analysis of the red king crab transcriptome and identifcation and characterization of its AMPs could potentially contribute to the development of novel antimicrobial drug candidates when antibiotic resistance has become a global health threat. In this study, we sequenced the P. camtschaticus transcriptomes from carapace, tail fap and leg tissues using an Illumina NGS platform. Libraries were systematically analyzed for gene expression profles along with AMP prediction. By an in silico approach using public databases we defned 49 cDNAs encoding for AMP candidates belonging to diverse families and functional classes, including buforins, crustins, paralithocins, and ALFs (anti-lipopolysaccharide factors). We analyzed expression patterns of 27 AMP genes. The highest expression was found for Paralithocin 1 and Crustin 3, with more than 8,000 reads. Other paralithocins, ALFs, crustins and ubiquicidins were among medium expressed genes. This transcriptome data set and AMPs provide a solid baseline for further functional analysis in P. camtschaticus. Results from the current study contribute also to the future application of red king crab as a bio-resource in addition to its being a known seafood delicacy.

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The bread-making quality of wheat depends on the viscoelastic properties of the dough in which gluten proteins play an important role. The quality of gluten proteins is influenced by the genetics of the different wheat varieties and environmental factors. Occasionally, a near complete loss of gluten strength, measured as the maximum resistance towards stretching (Rmax), is observed in grain lots of Norwegian wheat. It is hypothesized that the loss of gluten quality is caused by degradation of gluten proteins by fungal proteases. To identify fungi associated with loss of gluten strength, samples from a selection of wheat grain lots with weak gluten (n = 10, Rmax < 0.3 N) and strong gluten (n = 10, Rmax ≥ 0.6 N) was analyzed for the abundance of fungal operational taxonomic units (OTUs) using DNA metabarcoding of the nuclear ribosomal Internal Transcribed Spacer (ITS) region ITS1. The DNA quantities for a selection of fungal pathogens of wheat, and the total amount of fungal DNA, were analyzed by quantitative PCR (qPCR). The mean level of total fungal DNA was higher in grain samples with weak gluten compared to grain samples with strong gluten. Heightened quantities of DNA from fungi within the Fusarium Head Blight (FHB) complex, i.e. Fusarium avenaceum, Fusarium graminearum, Microdochium majus, and Microdochium nivale, were observed in grain samples with weak gluten compared to those with strong gluten. Microdochium majus was the dominant fungus in the samples with weak gluten. Stepwise regression modeling based on different wheat quality parameters, qPCR data, and the 35 most common OTUs revealed a significant negative association between gluten strength and three OTUs, of which the OTU identified as M. majus was the most abundant. The same analysis also revealed a significant negative relationship between gluten strength and F. avenaceum detected by qPCR, although the DNA levels of this fungus were low compared to those of M. majus. In vitro growth rate studies of a selection of FHB species showed that all the tested isolates were able to grow with gluten as a sole nitrogen source. In addition, proteins secreted by these fungi in liquid cultures were able to hydrolyze gluten substrate proteins in zymograms, confirming their capacity to secrete gluten-degrading proteases. The identification of fungi with potential to influence gluten quality can enable the development of strategies to minimize future problems with gluten strength in food-grade wheat.

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Rhodiola rosea L. (roseroot) is an adaptogen plant belonging to the Crassulaceae family. The broad spectrum of biological activity of R. rosea is attributed to its major phenyletanes and phenylpropanoids: rosavin, salidroside, rosin, cinnamyl alcohol, and tyrosol. In this study, we compared the content of phenyletanes and phenylpropanoids in rhizomes of R. rosea from the Norwegian germplasm collection collected in 2004 and in 2017. In general, the content of these bioactive compounds in 2017 was significantly higher than that observed in 2004. The freeze-drying method increased the concentration of all phenyletanes and phenylpropanoids in rhizomes compared with conventional drying at 70 °C. As far as we know, the content of salidroside (51.0 mg g−1) observed in this study is the highest ever detected in Rhodiola spp. Long-term vegetative propagation and high genetic diversity of R. rosea together with the freeze-drying method may have led to the high content of the bioactive compounds observed in the current study.

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The EU has developed a Directive on Sustainable Use of Chemical Pesticides (2009/128/EC) (SUD) that aims to enhance the use of non-chemical alternatives to pesticides like microbial plant protection products (PPP). The number of authorized microbial PPP for plant protection has increased globally during the last decade. There is, however, variation between different countries. Sweden and Denmark have for example each authorized 20 microbial PPP while Norway has only authorized four microbial PPP. Norway has also received significantly fewer applications for authorization of microbial PPP than the other Scandinavian countries. We explore possible explanations for the observed differences. Our results show that that the regulations in the three countries had similar requirements for the authorisation of microbial PPP. The size of the market is somewhat smaller in Norway than in Sweden and Denmark, and could therefore explain some of the differences. We suggest, however, that the most important explanation is implementation differences in terms of different decisions made in the authorization process. By comparing the authorization process for three microbial PPP in the Scandinavian countries, we found that Norway used more time for the product authorization decisions. Norway assess the same types of microbial PPP more restrictively with respect to environmental aspects and especially human health risks.

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Norwegian pear production is low due to climatic limitations, a lack of well-adapted cultivars and suitable pollinizers. However, nowadays it is increasing as a result of newly introduced and bred pear cultivars. Since cross pollination is necessary for high yields and good fruit quality, the aim of this investigation was to find the most suitable pollinizers for the pear cultivars “Ingeborg” (“Conference” × “Bonne Louise”) and “Celina” (“Colorée de Juillet” × “Williams”). Self-pollination of “Ingeborg” and “Celina”, together with “Conference”, “Belle Lucrative”, “Anna”, “Clara Frijs”, “Herzogin Elsa”, “Kristina” and “Fritjof” as potential pollinizers, were studied in this experiment during the 2017 and 2018 seasons in Norway. The success rate of each pollinizer was tested under field conditions, while the monitoring of pollen tube growth was done using the fluorescence microscopy method. All reproductive parameters (pollen germination, number of pollen tubes in the upper part of the style, pollen tube number in the locule of the ovary, number of fertilized ovules, initial fruit set, and final fruit set) in all crossing combinations were higher in 2018 due to much warmer weather. Based on the flowering overlap and success rate of each individual pollinizer and fruit set, the cultivars “Anna” and “Clara Frijs” can be suggested as pollinizers for the cultivar “Ingeborg”, while “Fritjof”, “Anna”, “Kristina” and “Herzogin Elsa” for the cultivar “Celina”. An even distribution of two compatible pollinizers having overlapping flowering times with the main commercial pear cultivar is a general recommendation for commercial pear production.

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Plants can form an immunological memory known as defense priming, whereby exposure to a priming stimulus enables quicker or stronger response to subsequent attack by pests and pathogens. Such priming of inducible defenses provides increased protection and reduces allocation costs of defense. Defense priming has been widely studied for short‐lived model plants such as Arabidopsis, but little is known about this phenomenon in long‐lived plants like spruce. We compared the effects of pretreatment with sublethal fungal inoculations or application of the phytohormone methyl jasmonate (MeJA) on the resistance of 48‐year‐old Norway spruce (Picea abies) trees to mass attack by a tree‐killing bark beetle beginning 35 days later. Bark beetles heavily infested and killed untreated trees but largely avoided fungus‐inoculated trees and MeJA‐treated trees. Quantification of defensive terpenes at the time of bark beetle attack showed fungal inoculation induced 91‐fold higher terpene concentrations compared with untreated trees, whereas application of MeJA did not significantly increase terpenes. These results indicate that resistance in fungus‐inoculated trees is a result of direct induction of defenses, whereas resistance in MeJA‐treated trees is due to defense priming. This work extends our knowledge of defense priming from model plants to an ecologically important tree species.

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In order to predict the effects of climate change on the global carbon cycle, it is crucial to understand the environmental factors that affect soil carbon storage in grasslands. In the present study, we attempted to explain the relationships between the distribution of soil carbon storage with climate, soil types, soil properties and topographical factors across different types of grasslands with different grazing regimes. We measured soil organic carbon in 92 locations at different soil depth increments, from 0 to 100 cm in southwestern China. Among soil types, brown earth soils (Luvisols) had the highest carbon storage with 19.5 ± 2.5 kg m−2, while chernozem soils had the lowest with 6.8 ± 1.2 kg m−2. Mean annual temperature and precipitation, exerted a significant, but, contrasting effects on soil carbon storage. Soil carbon storage increased as mean annual temperature decreased and as mean annual precipitation increased. Across different grassland types, the mean carbon storage for the top 100 cm varied from 7.6 ± 1.3 kg m−2 for temperate desert to 17.3 ± 2.9 kg m−2 for alpine meadow. Grazing/cutting regimes significantly affected soil carbon storage with lowest value (7.9 ± 1.5 kg m−2) recorded for cutting grass, while seasonal (11.4 ± 1.3 kg m−2) and year-long (12.2 ± 1.9 kg m−2) grazing increased carbon storage. The highest carbon storage was found in the completely ungrazed areas (16.7 ± 2.9 kg m−2). Climatic factors, along with soil types and topographical factors, controlled soil carbon density along a soil depth in grasslands. Environmental factors alone explained about 60% of the total variation in soil carbon storage. The actual depth-wise distribution of soil carbon contents was significantly influenced by the grazing intensity and topographical factors. Overall, policy-makers should focus on reducing the grazing intensity and land conversion for the sustainable management of grasslands and C sequestration.

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Land-sea riverine carbon transfer (LSRCT) is one of the key processes in the global carbon cycle. Although natural factors (e.g. climate, soil) influence LSRCT, human water management strategies have also been identified as a critical component. However, few systematic approaches quantifying the contribution of coupled natural and anthropogenic factors on LSRCT have been published. This study presents an integrated framework coupling hydrological modeling, field sampling and stable isotope analysis for the quantitative assessment of the impact of human water management practices (e.g. irrigation, dam construction) on LSRCT under different hydrological conditions. By applying this approach to the case study of the Nandu River, China, we find that carbon (C) concentrations originating from different land-uses (e.g. forest, cropland) are relatively stable and outlet C variations are mainly dominated by controlled runoff volumes rather than by input C concentrations. These results indicate that human water management practices are responsible for a reduction of ∼60% of riverine C at seasonal timescales, with an even greater reduction during drought conditions. Annual C discharges have been significantly reduced (e.g. 77 ± 5% in 2015 and 39 ± 11% in 2016) due to changes in human water extraction coupled with climate variation. In addition, isotope analysis also shows that C fluxes influenced by human activities (e.g. agriculture, aquaculture) could contribute the dominant particulate organic carbon under typical climatic conditions, as well as drought conditions. This research demonstrates the substantial effect that human water management practices have on the seasonal and annual fluxes of LSRCT, especially in such small basins. This work also shows the applicability of this integrated approach, using multiple tools to quantify the contribution of coupled anthropogenic and natural factors on LSRCT, and the general framework is believed to be feasible with limited modifications for larger basins in future research.