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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.

2016

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Abstract

Shelf life of plum is limited by several factors, including development of fungal decay. In either one or two seasons, European plum cultivars were exposed to different applications of calcium or fungicide before harvest or left unsprayed. On the experimental trees, the yield was harvested as commercial practice, giving a sample of fruit with a range in maturity acceptable for sale. The yield was divided into two groups, less and more ripened fruit. Fruit samples from each group were stored for 10-14 days at 4°C followed by a simulated shelf life period of 2-3 days at 20°C. Fruit quality was assessed at harvest and after storage. Number of fruit with fungal decay was counted at the end of storage and after simulated shelf life. At harvest, the more ripened fruit had higher weight, soluble solids content, background and cover colour, and lower firmness in most of the experiments. Fruit from trees sprayed six times with calcium had higher weight in first year, but not in second, was less ripen as measured by colour and firmness on some cultivars, but not on others. Time of fungicide application had no effect on fruit quality at harvest. Differences in fruit quality at harvest were most often similar after storage. Fruit grouped as more mature at harvest developed more fungal decay after simulated shelf life than less mature fruit in five of eight experiments. In one out of six experiments calcium applications reduced development of postharvest fungal decay. Fungicide applications had no effect on postharvest fungal decay in either of four experiments. The present results indicate that the ripening degree of plum fruit is more important for development of fungal decay than preharvest applications of calcium or fungicides

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Abstract

Key priorities in biochar research for future guidance of sustainable policy development have been identified by expert assessment within the COST Action TD1107. The current level of scientific understanding (LOSU) regarding the consequences of biochar application to soil were explored. Five broad thematic areas of biochar research were addressed: soil biodiversity and ecotoxicology, soil organic matter and greenhouse gas (GHG) emissions, soil physical properties, nutrient cycles and crop production, and soil remediation. The highest future research priorities regarding biochar’s effects in soils were: functional redundancy within soil microbial communities, bioavailability of biochar’s contaminants to soil biota, soil organic matter stability, GHG emissions, soil formation, soil hydrology, nutrient cycling due to microbial priming as well as altered rhizosphere ecology, and soil pH buffering capacity. Methodological and other constraints to achieve the required LOSU are discussed and options for efficient progress of biochar research and sustainable application to soil are presented.

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Abstract

Background: Many wingless ectoparasites have a limited capacity for active movement and are therefore primarily dependent on hitchhiking on their hosts for transportation. The distribution of the tick Ixodes ricinus is expected to depend mainly on transportation by hosts and tick subsequent survival in areas where they drop off. In Europe, the most important hosts of adult female I. ricinus are cervids. The extensive space use of large hosts provides a much larger dispersal potential for I. ricinus than that of smaller mammalian hosts. We aim to determine the contribution of red deer (Cervus elaphus) space use on the spatial distribution of I. ricinus, after accounting for landscape factors. Methods: We analysed the spatial distribution of I. ricinus with generalised mixed effects models (GLMMs) based on data from extensive field surveys of questing density in two coastal regions in Norway, from which home range data from 73 red deer with GPS collars were available. Red deer home ranges were derived using the kernel method to identify areas most frequently used by deer. We first fitted a baseline model with tick questing densities relative to landscape features that are likely to affect local climate conditions and hence, survival. We then added deer space use variables to the baseline model with only landscape variables to test whether areas more frequently used by red deer had higher questing tick densities. Results: Questing I. ricinus density was predicted by several landscape features, such as elevation, distance to the fjord and topographic slope. In addition, we found that areas more heavily used within the red deer home ranges, correlated with higher questing tick densities. Increased effects of deer space use were additive to the landscape model, suggesting that correlations were more than just shared landscape preferences between deer and ticks. Conclusions: Our results imply that the distribution of I. ricinus is controlled by a complex set of factors that include both local conditions related to landscape properties that affect survival and how the large host population redistributes ticks. In particular, we have provided evidence that the local distribution of large hosts, with their extensive space use, redistributes ticks at the local scale.