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
Authors
Maria Hayes Leen Bastiaens Luisa Gouveia Spyros Gkelis Hanne Skomedal Kari Skjånes Patrick Murray Marco García-Vaquero Muge Isleten Hosoglu John Dodd Despoina Konstantinou Ivo Safarik Graziella Chini Zittelli Vytas Rimkus Victόria del Pino Koenraad Muylaert Christine Edwards Morten Laake Joana Gabriela Laranjeira da Silva Hugo Pereira Joana AbelhoAbstract
No abstract has been registered
Authors
Mekjell Meland Milica Fotiric-Aksic Dragan RadivojevicAbstract
European plums (Prunus domestica L.) blossom abundantly most years and often set too many flowers. If these excessive numbers of fruitlets remain on the trees until harvest, the crop would consist of small, unmarketable fruits of low fruit quality. Thinning agents like ammoniumthiosulphate (ATS), sulphur and soya oil desiccate flowers, especially stigma, which is the most sensitive tissue part of the flower. This way, the main effect of blossom thinning treatments is the disruption of pollination and fertilization. Thinning trials were conducted at a commercial orchard near the shore of the Hardangerfjord near Nibio Ullensvang, western Norway (60.2°N) on mature ‘Jubileum’ trees, all grafted on ‘St. Julien A’ rootstock. The trees were treated with 0.4, 0.8, 2 and 4% sulphur; a mixture of 0.4% sulphur + 2% soya oil and 1.5% ATS (liquid and powder formulations), at full bloom. All treatments were compared with hand-thinned and unthinned trees which were used as a control. Experimental trees were sprayed to the point of run-off with a hand sprayer during May 2008 and 2009 at full bloom. Flower thinners were efficient at relatively low temperatures which is a benefit in a cooler climate. In 2008 all thinning treatments reduced fruit set compared to unthinned controls for all cultivars. Sulphur and soya oil, both alone and in combination, were significantly less effective than ATS. In 2009, fruit set was higher and the effects of all thinning agents were lower. Fruit set decreased with increasing sulphur concentrations, but fruit thinning was not sufficient, even at the highest concentration. Both the liquid and powder formulations of ATS gave the same thinning effects. For all thinning treatments, both significant yield reductions and fruit weight increment were noticed during the experimental period. Fruit over color and soluble solids were generally higher and increased significantly with lower crop load, while fruit firmness (Durofel) and total acidity were less affected. In conclusion, different concentrations of sulphur had a moderate thinning effect and are not recommended for use as plum thinners under these conditions. Instead, 1.5% ATS application, (liquid and powder) applied at full bloom, resulted in adequate thinning of ’Jubileum’ plums under cool mesic northern climatic conditions.
Authors
Tore SkrøppaAbstract
No abstract has been registered
Authors
Tore SkrøppaAbstract
No abstract has been registered
Abstract
In cold climate regions a significant fraction of annual soil erosion in agricultural land occurs during snowmelt and rain on partially frozen soils. Physically based and spatially distributed soil erosion models have proved to be good tools for understanding the processes occurring at catchment scale during rainfall erosion. However, most existing erosion models do not account for snow in a suitable way. A combination of the UEBGrid snow pack model and the LISEM erosion model was therefore used in this study. The aim was to test and validate this model combination and to assess its utility in relation to quantification and process understanding. Applying this model combination to simulate surface runoff and soil erosion showed that, in principle, it is possible to satisfactorily simulate surface runoff and observed soil erosion patterns during winter. The values for the calibration parameters were similar for the two chosen winter periods when the rainfall and snowmelt episodes occurred. However, the calibration procedure showed that the utility of this combination had several limitations. It is hoped that this study can help to improve existing models and trigger new developments in including snow pack dynamics and soil freezing and thawing in soil erosion models.
Abstract
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No abstract has been registered
Authors
Klaus Mittenzwei Wolfgang BritzAbstract
No abstract has been registered
Authors
Adam O'Toole Christophe Moni Simon Weldon Anne Schols Monique Carnol Bernard Bosman Daniel RasseAbstract
No abstract has been registered
Abstract
No abstract has been registered