Hopp til hovedinnholdet

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.

2025

To document

Abstract

The effect of harvest timing on postharvest ripening was investigated by changes in ethylene production, expression of ethylene biosynthesis genes MdACS1, MdACS6, (1-aminocyclopropane-1-carboxylic acid synthase 1 and 6) and the ACS degradation promoting gene MdETO1 (Ethylene overproducer 1). Apple fruit of two cultivars, ‘Red Aroma’ and ‘Rubinstep’, were harvested at three time points, early, middle, and late, at two-week intervals. Fruit were either treated with 1 ppm 1-Methylcyclopropene (1-MCP) or remained untreated, and stored at 4 °C in regular atmosphere. Late harvested, untreated apples reached peak ethylene production after the shortest time in cold storage ('Red Aroma' in week five, 'Rubinstep' in weeks nine and ten), while early harvested, untreated fruit reached their peak after a longer time ('Red Aroma' in week eight, 'Rubinstep' in weeks 13 and 14). Early harvested fruit experienced greater firmness loss and a higher increase in SCC/TA ratio during cold storage. Senescence in late harvested, untreated fruit was evident from low ethylene production after simulated shelf-life and increased physiological disorders in ‘Rubinstep’. In 1-MCP-treated fruit, ethylene production increased toward the end of storage, particularly in early harvested fruit, indicating a decline in 1-MCP efficacy over time. Gene expression analysis showed strong induction of MdACS1 during climacteric ripening. MdETO1 positively correlated with MdACS1 gene expression, suggesting positive co-regulation. The expression of MdACS6 was negatively correlated with simulated shelf-life and with 1-MCP treatment, suggesting regulation by temperature and metabolic state. Overall, harvest timing and 1-MCP strongly influenced the changes in fruit physiology during postharvest storage.

To document

Abstract

Cervid (Cervidae) populations that are overabundant with respect to their food resources are expected to show declining physiological and reproductive fitness. A proactive solution to such declines is to integrate the monitoring of food resources with animal harvesting strategies, but there are few studies available to guide managers regarding which food resources to monitor and how to do so. In this study, we used a large, rare data set that included detailed absolute measures of available food quantities and browsing intensity from field inventories, to test their relationship with fitness indices of moose Alces alces in 24 management units in four regions across Norway. We found that calf body mass and calves seen per cow during the autumn hunt were strongly and positively related to the availability of tree forage, especially the species most selected for by the study moose (e.g., rowan [ Sorbus aucuparia ] and sallow [ Salix caprea ]). The strength of the correlations varied between regions, apparently being stronger where the moose were closer to being overabundant or had a legacy of past overabundance. As expected, the intensity of browsing on the three most common tree species, that is, birch ( Betula spp.), rowan, and pine ( Pinus sylvestris ), was also negatively and strongly related to the fitness. We discuss how our approach to food monitoring can facilitate a management that proactively adjusts densities of moose, and possibly other cervids, to trends in food availability and browsing intensity, thereby avoiding detrimental effects of overabundance.