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.
2026
Abstract
Purpose Advanced remote sensing and imagery technology help to estimate variability in grass ley plant coverage (PC). Adjusted manure and fertiliser application rates can be derived according to this variability, by means of machine learning and advanced image processing. This study aimed to determine the effects of variable nitrogen (N) rate from manure and synthetic fertiliser application on a grass ley field experiment in southwestern Norway, thereby generating N rate recommendations. The effects on dry matter yield, N use efficiency, and forage nutritive value were determined. Methods A field experiment was conducted in 2022-2023 and repeated in 2023-2024, estimating PC using digital processing of autumn and spring aerial images to determine fertiliser rates. Three fixed and two variable manure and mineral N rates were applied in early spring and after the first and second cuts. Forage dry matter yield (FDMY) and agronomic N use efficiecy (AgNUE) were evaluated over two seasons. Results A low or variable N rate based on spring coverage led to FDMY and AgNUE comparable to high N rates. Spring and autumn coverage during the second season improved slurry application decisions, offering a valuable tool for grassland management. The N rate-response model effectively represented the nonlinear behaviour of FDMY, revealing a strong concave response to N rates, significant seasonal variations, and a notable flattening of the response in 2024. Predicted curves indicated that the most beneficial N application occurs in earlier cuts, as late-season applications showed diminished yield leverage under 2024 conditions. Conclusion Image analysis can effectively support variable-rate fertiliser recommendations for perennial grasslands, although such approaches only improved N usage in one of two years. Whilst variable-rate application (VRA) is resilient during constrained regrowth years, interannual weather variability and seasonal conditions significantly influenced N responsiveness, indicating the necessity for calibrating cover-based models to enhance nutrient management efficiency under varying climate conditions.
Authors
Larisa Garkava-Gustavsson Jonas Skytte af Sätra Oksana Korniienko Marina Kuzmenkova Kateryna Udovychenko Darius KviklysAbstract
Abstract Key Message This study revealed considerable variation in resistance to European canker caused by Neonectria ditissima among apple rootstocks, rootstock impact on resistance to the disease in scion cultivars, and rootstock × scion interaction effects. Abstract European canker caused by Neonectria ditissima is a serious disease on apple and pear, posing a major threat to Swedish and Northern European commercial apple production. Efforts to develop cultivars with improved resistance are ongoing, but far from reaching the commercial market due to the long breeding cycles of apple. Thus, short-term strategies to mitigate the disease are essential, and the susceptibility of the scion cultivar may be influenced by the rootstock it is grafted to. Here, we screened 23 rootstocks representing 21 unique rootstock genotypes, including a number of clones of ‘M.9’, for their levels of resistance to European canker over two years. Two rootstocks were received from two or three different nurseries. We found significant differences in resistance among the rootstocks, and related this to their genetic structure, which was estimated with 16 SSR loci. Rootstock ‘G.969’ was found as being significantly more resistant than all other tested rootstocks and had a positive effect on scion resistance. We also investigated rootstock × scion interactions using seven rootstocks and four scion cultivars that are important within Swedish commercial production. We observed a moderate but not significant correlation between rootstock resistance and its effect on scion resistance, but also interaction effects between specific rootstock-scion combinations. Our findings highlight the valuable contribution of modern breeding efforts in tackling one of the major challenges, provide valuable information for commercial cultivation practices, and illustrate the intricate interaction effects influencing disease resistance.
Authors
Chaochu Fang Minyan Wang Cheng Shen Yun Shi Jun Dong Lei Luo Su Shiung Lam Yin Wang Ming Hung Wong Nicholas Clarke Lei Wang Jin ZhangAbstract
No abstract has been registered
Abstract
Smolt production in freshwater is an essential component of the salmonid aquaculture production chain. But it generates sludge (feed waste and fish feces) that must be managed to meet environmental regulations. While sludge can be reused as a resource, there are limited empirical results about cost structures, market conditions, and energy implications in industrial aquaculture. This study analyzes sludge collection, processing, and utilization based on a single-case study of a Norwegian smolt producer (Sisomar AS). The analysis combines company-level production data, accounting information, and process descriptions. In 2023, the company produced approximately 9.2 million smolt (1184 tons of biomass), generating 140 tons of dried sludge. Sisomar’s value creation from production of bio-based fertilizer from sludge is relatively close to that of comparable mineral fertilizers, but a direct comparison here is difficult because of large variations in the prices of mineral fertilizers. The energy consumption is significantly lower for organic fertilizer from Sisomar compared to standard technology for mineral fertilizer production. Bio-based fertilizers are looked at as an important contribution to dealing with environmental challenges, and this study discusses the characteristics of how market structures have importance for this.
Authors
Miguel Las Heras Hernandez Francis Isidore Barre Nils Maximilian Dittrich Thomas Galea Marceau Jean-Paul Christian Cormery Avijit Vinayak Pandit Romaine Guillaume Billy Anna Eide Lunde Anne Falk Øgaard Daniel Beat MuellerAbstract
No abstract has been registered
Authors
Julaluck Intasin Hannah M Rivedal Nicole P Anderson Alec R Kowalewski Yanming Di Navneet KaurAbstract
Abstract Epichloë spp. grow symbiotically within cool-season grasses and can provide crop protection against pests and drought stress. Winter cutworm (Noctua pronuba L.) is a serious insect pest of cool-season turfgrass and grass seed crops in Oregon (United States). In 2023, we conducted 2 greenhouse experiments to measure the effect of Epichloë infection in 8 cultivars of tall fescue (Schedonorus arundinaceus (Schreb.) Dumort) and perennial ryegrass (Lolium perenne L.) on N. pronuba mortality, weight gain, grass biomass, and feeding damage at 3 time points. Epichloë infection in grass plants was molecularly validated postexperiment. We did not observe an effect of Epichloë infection level or grass cultivar on N. pronuba, regardless of grass species in trial 1. In trial 2, Epichloë infection level effects remained minimal, while cultivar affected feeding damage at 3 and 12 d in both grass species. Feeding damage at 15 d did not vary among cultivars in both tall fescue and perennial ryegrass due to continuous and severe defoliation by N. pronuba. Insect mortality and weight gain were different among tall fescue cultivars. However, some cultivars were forage type, which was selected to be palatable to grazing animals, and could be preferred by the larvae. The perennial ryegrass cultivars were all turf-type and showed no variability in insect responses. The observed feeding damage variations were likely associated with cultivar-specific traits rather than Epichloë infection levels. Understanding the role of grass genotype in grass–Epichloë symbioses is critical to develop practical management for N. pronuba, and other cutworm species.
Abstract
The sensory appeal of strawberry (Fragaria × ananassa) depends on its chemical composition, including sugars, organic acids, and aroma-active volatiles. To investigate the effects of temperature and light conditions on fruit quality, strawberry plants (cv. Sonsation) were grown at six temperature regimes (9, 12, 15, 18, 21 °C, and 21/9 °C-day/night) and four combinations of light intensities (150 and 300 μmol/m2/s) and photoperiods (12 and 24 h/day). Yield, °Brix/acidity ratio and volatile compounds were assessed. °Brix increased with light intensity and photoperiod, while higher temperatures (15–21 °C) correlated with acidity. A favorable °Brix/acidity ratio correlated with both continuous light and high light intensity, as well as low ripening temperature. Volatile content peaked at 15 °C, and declined at 9 °C, proportionally elevating acids and reducing terpenoids. The findings indicate that extended high-intensity light can optimize sweetness and aroma in cv. Sonsation, whereas low temperatures benefit the °Brix-acidity balance but may reduce volatile compound development.
Abstract
No abstract has been registered
Authors
Irene Kagiampaki Manolis Mandalakis Thekla I Anastasiou Lampros Lamprinakis Valborg KvakkestadAbstract
No abstract has been registered
Abstract
Are ecological scaling relationships stable through time, or can shifting parameters signal “quiet” community reorganization before diversity loss becomes evident? Using a century-long resurvey of subalpine and alpine vegetation along an elevational gradient in Norway, we tested whether key scaling relationships linking (I) spatial extent to diversity, (II) elevational distance to compositional and functional dissimilarity, and (III) species commonness to occupancy have remained stable through time. In 2008 and 2022, we resurveyed semi-permanent plots in central Norway first sampled in 1923–1933 along 995–1495 m.a.s.l., aggregating plots into 50-m elevational belts. We quantified spatial scaling of diversity with area, community differences across elevation, and relationships linked to species commonness and occupancy. Scaling relationships revealed a reorganization that is not captured by richness alone. Large-scale community structuring across elevation remained remarkably stable over the past century, with largely unchanged species– area relationships, beta and zeta diversity, and abundance–occupancy relationships. Despite this, absolute dissimilarity across elevational belts declined with beta diversity increasingly driven by species turnover while the nestedness component weakened. Communities also became progressively characterised by more widespread, common species and a more even abundance distribution, in addition to a convergence of ecological preferences. While the elevational gradient has not collapsed into a uniform assemblage, key scaling parameters within the gradient have shifted. These changes suggest a gradual compositional and functional reorganization of the vegetation that might for now maintain ecosystem functioning through dominant generalists, while quietly eroding long-term ecosystem resilience through species losses.