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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.

2018

Abstract

The effect of controlled nutrient feeding during the period of short day (SD) induction of flowering has been studied in three SD berry crops. An experimental system with standardized plant material grown with trickle fertigation in controlled environments was used. In strawberry, flowering was advanced and increased when an additional N pulse was given 1-2 weeks after commencement of a 4-week SD induction period, while the opposite resulted when the treatment was applied 2 weeks before start of SD. In blackcurrant, the highest flowering and yield were obtained when fertilization was applied shortly after the natural photoperiod had declined to the inductive length in September. While generous nutrient supply during spring and summer reduced berry soluble solids in blackcurrant, this was not observed with autumn fertilization. Autumn fertilization did not adversely affect plant winter survival or growth vigour in spring. Withdrawal of fertilization prior to, or at various stages during floral induction, did not significantly affect flowering and yield in raspberry, but marginally advanced flowering and fruit ripening.

Abstract

We examined the influence of fertigation on vegetative and generative parameters of strawberry plants (Fragaria × ananassa Duch.) and evaluated rapid analysing tools for N and K in leaf tissue. The experiments were undertaken in an open polytunnel on “table top” with ‘Sonata’ and ‘Korona’ grown in 2-L pots filled with a peat-based soil mixture. The experimental design was a randomized plot with three replications. Plants were fertigated with EC levels of 0.5, 1.0, 1.5 and 2.0 mS cm-1, based on two stock solutions of 7.5 kg YaraLiva™ Calcinit and 7.5 kg Kristalon™ Indigo, both dissolved in 100 L of water. Percentage N and K in leaves differed between analysing methods, cultivars, EC and date. We found interactions between the cultivar and EC level and between date and cultivar for N and K in leaf. Analysing NO3- by a photometric method (PM) in a lab, and by Laqua twin (LT), showed significant interaction with N% of leaf dry matter (DM) only for LT (r2=0.36). N% increased with higher EC level, more for ‘Korona’ than for ‘Sonata’. LT K+ did not correlate with K% (r2=0.014). The number of crowns and runners increased for both cultivars up to EC 1.5, while the number of leaves was unaffected. Petioles were the shortest at the lowest EC. Flower initiation was earlier at low EC in both cultivars. In the following spring, the time to flowering and first harvest was reduced with the decreasing EC. The number of flowers per plant increased up to EC 1.5, but dropped strongly at EC 2.0 for ‘Korona’, while ‘Sonata’ had a gradual increase of flowers with the increasing EC, but the number was only a third of ‘Korona’, except at EC 2.0, where the amount was equal for both cultivars. The conclusion can be drawn that LT correlated better than ChlDualex with N in strawberry leaves. However, r2 was only 0.36 indicating that LT NO3- is a coarse management tool. LT K+ was not a promising tool for rapid K+ test in these experiments. ‘Korona’ seemed to benefit of higher N levels for both vegetative growth and generative development than ‘Sonata’ up to EC 1.5, but ‘Sonata’ reached a higher floral primordia development stage in early October.

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Abstract

The project “Sustainable food production through quality optimized raw-material production and processing technologies for premium quality vegetable products and generated by-products” [SUNNIVA] aimed at the development of a sustainable food system from production to consumption, addressing the entire food supply chain for the vegetables tomato and Brassicae. The goal was better utilisation of the vegetable raw materials, reduced energy and water consumption, higher profitability and healthier food. This was achieved by providing various valorisation strategies to reduce waste and limiting environmental impact. Preservation of the intrinsic health-beneficial phytochemicals present in the raw material in order to improve the nutritional properties of vegetable food products was central in the project. The project contained optimization of harvest time and pre-processing storage conditions, development of novel mild processing design based on modelling, and a two-track valorisation strategy. SUNNIVA has demonstrated how the various residual raw materials can be exploited to the full: Either directly for sustainable production of healthy food (as a refined product or an ingredient), or indirectly by bringing it back into the food chain (as organic fertilizers and soil amendment products) in order to generate renewed primary production with minimal environmental impact.

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Abstract

This study examines the relationships between profitability, nitrogen (N) surplus, greenhouse gas emissions (GHG), and energy intensity and factors influencing these relationships in dairy farming. In-depth data from 10 conventional and 8 organic dairy farms in Western Norway were analyzed. Organic farms had lower N surplus per hectare (local, onfarm) and per unit output (global, cradle-to-farm-gate), and lower estimated GHG emissions and energy intensity per unit output, whereas labor input and farm profits did not differ. Higher profitability tended to be associated with improved performance of the environmental indicators examined. Intensification through increased use of concentrates tended to improve profit and reduce N surplus, GHG emissions, and energy intensity per unit output within each farming system while N surplus per hectare could be negatively affected. To ensure a balanced representation of the environmental consequences of both organic and conventional farming systems,our results give support to extensive examination of both area and product-based environmental performance indicators.