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.
2012
Authors
Eivind Uleberg Jens Rohloff Laura Jaakola Kajetan Trost Olavi Junttila Hely Häggman Inger MartinussenAbstract
After pollination outdoors individual bilberry plants from two Northern and two Southern clones were studied for climatic effects on berry yield and quality in a controlled phytotrone experiment at 12 °C and 18 °C. At each temperature the following light treatments were tested; 1) 12 h natural light; 2) 24 h natural light and 3) 24 h natural light plus red light. The first experimental year there was no difference in yield between temperatures, however, the second experimental year the berry yields was significantly higher at 18 °C. Berry ripening was faster in the Northern than in the Southern clones at 12 °C. Northern clones also showed significantly higher contents of total anthocyanins, all measured anthocyanin derivatives, total phenolics, malic acid and sucrose. Metabolic profiling revealed higher levels of flavanols, hydroxycinnamic acids, quinic acid and carbohydrates at 12 °C.
Abstract
Bilberry (Vaccinium myrtillus L.), also called European blueberry, is native to Norway and strongly preferred by the Norwegian food industry due to its genuine flavour and high content of phytochemicals. However, Norwegian natural resources are underexploited, and only few investigation have focused on quality aspects of bilberries from wild populations with regard to potential cultivation and industrial utilization. Important goals of the 4-years study were to investigate (a) Berry quality parameters, (b) Fertilization effects, and (c) Geographic and seasonal variation in trial locations at regions in Southern, Mid and Northern Norway. Berry quality assessment included parameters such as total anthocyanins (ACY) and phenols (TPH), antioxidant capacity (AOX), pH, titratable acidity (TAC) and soluble solids (SS). Based on multivariate statistics (PCA), regional segregation patterns could be observed which were strongly overlapped by year-to-year variation. Within-seasonal variation of parameters were recorded for berries harvested at different time points throughout the season (Southern location/ Hedmark), but between-seasonal effects were generally stronger. Similar year-to-year effects were also found in bilberries from Northern Norway (Bardu), but not in berries harvested from the field in Mid Norway/Langvatnet. The field in Northern Norway was treated with organic fertilizer (compost and wood chippings), while the field in Mid Norway was fertilized with mineral fertilizer combinations (N+P). Application of organic fertilizer did not have any clear effect on berry quality, while mineral fertilizer resulted in clear segregation patterns of berry samples after three years of treatment, thus minimizing year-to year variation. Mean values of quality parameters ACY, TPH and AOX, measured at the different locations (all years and treatments) varied between 330-427 mg/100 g f.w., 531-640 mg/100 g f.w., and 5-8 mmol/100 g f.w., respectively, thus underscoring the phytochemical value of bilberries from Norwegian populations.
Abstract
No abstract has been registered
Authors
Jens Rohloff Eivind Uleberg Laura Jaakola Kajetan Trost Olavi Junttila Hely Häggman Inger MartinussenAbstract
Individual bilberry plants from two Northern and two Southern clones were studied for climatic effects on production and quality in a controlled phytotrone experiment at 12 °C and 18 °C in a 2-year trial. At each temperature the following light conditions were tested: 1) 12 h natural light (short day); 2) 24 h natural light (long day) and 3) 24 h natural light (long day) plus red light. In order to ensure sufficient and comparable fruit set between treatments, flower pollination was executed outdoors. Berry yield, quality parameters such as total anthocyanins, total phenols and antioxidant capacity, and chemical composition (GC/MS-based metabolite profiling) were recorded in both years, while HPLC-based anthocyanin analysis was only carried out in the second year. All analyzed compounds showed significant year-to-year variation with the exception of antioxidant activity. The experiment was conducted under natural light conditions, and therefore light intensity and quality varied between the two growing seasons. The first experimental year there was no difference in yield between temperatures, however, the second experimental year the berry yield was significantly higher at 18 °C. Temperature treatments led to faster berry ripening in the Northern than in the Southern clones at 12 °C. Metabolite profiling also revealed higher levels of flavanols, hydroxycinnamic acids, quinic acid and carbohydrates at 12 °C. Clonal effects showed that the content of all anthocyanin derivatives, as well as levels of antioxidants, total phenolics, malic acid and sucrose were highest in the Northern clones, while Southern clones had higher levels of hydroxycinamic acids, epicatechin, quinic acid and myo-inositol. Northern clones were also more responsive to additional red light with highest levels of anthocyanins under long-day treatment.
Authors
Inger Martinussen Jens Rohloff Laura Jaakola Kajetan Trost Olavi Junttila Hely Häggman Eivind UlebergAbstract
The effects of climate on production and the quality of bilberries have been studied in a controlled phytotrone experiment using clonal material originating from Northern and Southern parts of Finland. In the experiment individual plants from two Northern clones and two Southern clones have been grown at 12° and 18°C. At each temperature 3 different light treatments have been tested; 1) 24 h natural light (long day), 2) 12 h natural light (short day) and 3) 24 h natural light with an addition of extra red light. All berries produced by each plant have been harvested at maturity and have been analyzed for several important quality parameters. The metabolic profiling results show that levels of flavonols (epicatechin and catechin), hydroxyl acids (chlorogenic acid, hydroxyl cinnamic acid), quinic acid and all analyzed carbohydrates (myo-inositol, fructose, glucose and sucrose) are highest at 12°C. On the contrary, total anthocyanins levels were highest at 18°C and this was also reflected in the results on analysis of several anthocyanins derivates with the exception of Del 3‑Ara that was significantly higher at 12°C than 18°C. Northern clones had significantly higher levels of total anthocyanins, all measured anthocyanin derivates, total phenols, malic acid and sucrose than Southern clones.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
Abstract: This paper reviews several studies of earthworms in agricultural soils in Norway. Crops and management significantly influence the earthworm fauna. Beneficial impacts of earthworms on plant growth are likely, but challenging to prove. Earthworm casts contain high amounts of extractable plant nutrients, which probably contribute to plant nutrient uptake. Geophagous (soil-eating) species such as Aporrectodea caliginosa and A.rosea dominate the earthworm fauna in our arable soils1. Lumbricus terrestris is also present and was found also in all-arable crop rotations with annual ploughing2. In southern Norway, L. rubellus and A. longa are also common. Earthworm populations, recorded in autumn, vary between 30 and 350 individuals m-2, with the lowest values found in all-arable systems2. The inclusion of leys in the crop rotation increases the abundance of channels, earthworm numbers and their biomass2. Since most earthworms prefer living in the upper soil layer, shallow ploughing (15 cm depth) might be expected to be detrimental. However we found that the number and biomass of earthworms was not lower with shallow than with deep ploughing (25 cm)1. In a study, green manure management affected the biomass, species and number of earthworms3. More worms were found in plots where the green manure was left on the field, compared with where it was removed. L. rubellus responded positively and rapidly to mulching, and so did A.caliginosa in clay soil. The use of biogas slurry from green manure in one season gave no effect on number and biomass of earthworms3. Long-term use of solid animal manure positively influenced some earthworm parameters, even three years after the last application1, compared to mineral fertilizer. Utilizing animal manure to produce biogas may reduce fossil fuel usage and emissions of greenhouse gases. However, there is limited information on how the recycling of digested manure as a fertilizer affects soil fertility in the long run. Reduced recycling of carbon to the soil, may harm soil fauna, including earthworms. In a newly started project on the organic research farm at Tingvoll, Norway, anaerobically digested manure is compared with undigested slurry in perennial ley and arable crops. Effects on crop yields, soil fauna, microbial communities, soil structure, organic matter and nutrient concentrations are being measured. Initial studies showed that several earthworm species were present (A.caliginosa, A.rosea, L.terrestris, L.rubellus, Octolasion cyaneum). Earthworm casts (excrements) from the detritivorous species L. terrestris (that feeds on plant residues) have been shown to be richer in nutrients than bulk soil, but little was known previously about the casts of geophagous species (that ingest mostly soil). Casts from two soil depths (13 and 25 cm) were collected by means of litter bags, to study whether such casts also contained more plant available nutrients than the bulk soil. A.caliginosa and A.rosea were the dominant species in these fields. The casts had considerably higher concentrations of plant nutrients than the bulk soil. The content of total-N was 28 % higher in casts, total-C was 37% higher, the contents of available P and K were 40-60%, whilst those of Ca and Mg were 10-20 % higher. On average for the two sites, these differences corresponded to the following amounts (kg ha-1 y-1): 5.6 for P, 8.9 for K, 5.3 for Mg, 144 for N and 2542 for C. With earthworm densities such as those found in farming systems incl. ley and animal manure (ca. 230 individuals m-2), about 220 tonnes of topsoil per hectare passes through the earthworm digestive tract each year. Our study indicated that earthworm casts are valuable sources of plant nutrients even in soils where the fauna is dominated by geophagous species.
Abstract
No abstract has been registered
Authors
Grete H. M. JørgensenAbstract
No abstract has been registered