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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2023

Abstract

Carrot is the main field vegetable in Norway and is stored at 0-1°C for up to 8 months. In long-stored carrots, postharvest diseases are problematic. Better knowledge of the causal agents of postharvest diseases can help producers apply appropriate control measures to reduce carrot loss and waste. The objectives of this study were to determine the extent of the tip rot problem and the prevalence of other storage diseases of carrots in different regions in Norway. The study was conducted from 2019 to 2021 by collecting carrots from 16 commercial cold storages, representing four regions. From each storage, representative carrots were randomly sampled, washed, and sorted into different disease categories and healthy carrots. Representative samples from each category were further analyzed in the NIBIO laboratory to identify the causal agent(s) and confirm the disease. Causal agent(s) were identified by symptom and sign description, microscopy and when necessary, DNA sequencing. One or more pathogens were identified from each symptomatic carrot. The incidence of postharvest diseases significantly varied among regions. Taking all years and regions together, only 42% of the carrots were healthy. In other words, 58% of the carrots were with one or more diseases, representing a waste due to diseases alone. Tip rot alone contributed to about 30% of the postharvest loss. Our results indicate that the burden of postharvest diseases of carrots is increasing. This includes diseases like tip rot disease complex, Cylindrocarpon root rot and cavity spot. The results are useful to direct research investigation of the most problematic diseases. Most of the post-harvest diseases of carrots are the result of latent infections that occur in the field, and stress during handling, storage, and processing operations. Hence, postharvest disease control measures should consider the pre-and postharvest predisposing factors of carrots for storage rot.

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Abstract

The large-scale import of soybean products into the EU decreases the self-sufficiency of livestock production. The fractionation of grassland forage crops presents an opportunity to locally produce protein-rich feed for monogastrics. Two promising fractionation methods, twin-screw press juicing and leaf stripping, were evaluated in parallel in field experiments established in Norway and Sweden to compare the nutrient composition and yield of the resulting biorefined and residual fractions. The clearest delineation between the methods was in the ash-free neutral detergent fibre (aNDFom) concentration, with juicing producing a biorefined fraction with a lower aNDFom than leaf stripping. Variability in the allocation of crude protein (CP) and biomass to the biorefined fractions occurred in both methods between cuts and locations and is likely due to differing stand characteristics and inconsistency in machine functionality. Additional work is needed to understand how characteristics such as stand density, botanical composition, and plant phenological stage impact each fractionation method’s ability to allocate protein, fibre, and biomass into the resulting fractions. Future studies should focus particularly on determining standardised settings for leaf stripping machinery based on a range of stand characteristics to ensure consistency in the yield and nutrient composition of the resulting fractions.

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Abstract

Faced with risky yields and returns, risk-averse farmers require a premium to take risks. In this paper, we estimate individual farmers’ degrees of risk aversion to adjust for the risk premium in returns and to replace the farmers’ realized returns with their certainty equivalent returns in the production function. In that way, the effect of the inputs on returns will automatically be risk-adjusted, i.e., we obtain risk-adjusted marginal effects of inputs, which can be used in decision-making support of farmers’ input choices in production. Using farm-level data from organic basmati rice smallholders in India, we illustrate this method using nonparametric production functions. The results show that the input elasticities and returns-to-scale estimates change when the farmers’ degree of risk aversion is taken into consideration.

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Abstract

This paper synthesizes a five-year project (BIOWATER) that assessed the effects of a developing bioeconomy on Nordic freshwaters. We used a catchment perspective and combined several approaches: comparative analyses of long-term data sets from well-monitored catchments (agricultural, with forestry, and near pristine) across Fennoscandia, catchment biogeochemical modelling and ecosystem services assessment for integration. Various mitigation measures were also studied. Benchmark Shared Socio-economic Pathways were downscaled and articulated in dialogue with national stakeholder representatives leading to five Nordic Bioeconomy Pathways (NBPs) describing plausible but different trajectories of societal development towards 2050.These were then used for catchment modelling and ecosystem service assessment. Key findings from the work synthesized here are: (a) The monitoring results from 69 catchments demonstrate that agricultural lands exported an order of magnitude more nutrients than natural catchments (medians 44 vs 4 kg P km−2 y-1 and 1450 vs 139 kg N km−2 y-1) whilst forests were intermediate (7 kg P km−2 y-1 and 200 kg N km−2 y-1). (b) Our contrasting scenarios led to substantial differences in land use patterns, which affected river flow as well as nutrient loads in two of the four modelled catchments (Danish Odense Å and Norwegian Skuterud), but not in two others (Swedish catchment C6 and Finnish Simojoki). (c) Strongly contrasting scenarios (NBP1 maximizing resource circularity versus NBP5 maximizing short-term profit) were found to lead to similar monetary estimates of total societal benefits, though for different underlying reasons – a pattern similar across the six studied Nordic catchments. (d) The ecological status of small to medium sized rivers in agricultural landscapes benefitted greatly from an increase in riparian forest cover from 10 % to 60 %. Riparian buffer strips, constructed wetlands, rewetting of ditched peatlands, and similar nature-based solutions optimize natural biogeochemical processes and thus can help in mitigating negative impacts of intensified biomass removal on water quality.