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.
2023
Abstract
Introduction: Greenhouse tomato growers face the challenge of balancing fruit size and chemical quality traits. This study focused on elucidating the interplay between plant branching and light management on these traits, while maintaining consistent shoot density. Methods: We evaluated one- and two-shoot plants under varying top light intensities using high-pressure sodium lamps and light-emitting diode (LED) inter-lighting. Results: The reduced yield in the two-shoot plants was mainly due to smaller fruit size, but not due to source strength limitations, as evaluated through leaf weight ratio (LWR), chlorophyll index, specific leaf area (SLA), leaf dry matter percentage, and stem soluble carbohydrate accumulation. Enhanced lighting improved fruit weight and various fruit traits, such as dry matter content, total soluble carbohydrate content, and phenolic content, for both one- and two-shoot plant types. Despite lower mean fruit weight, two-shoot plants exhibited higher values for chemical fruit quality traits, indicating that the fruit growth of two-shoot plants is not limited by the available carbohydrates (source strength), but by the fruit sink strength. Diurnal analysis of fruit growth showed that two-shoot plants had reduced expansion during light transitions. This drop in fruit expansion was not related to changes in root pressure (measured as xylem sap exudation from decapitated plants), but might be related to diminished xylem area in the stem joint of the two-shoot plants. The concentration of several hormones, including cytokinins, was lower in two-shoot plants, suggesting a reduced fruit sink capacity. Discussion: The predominant impact of branching to two-shoot plants on sink capacity suggests that the fruit growth is not limited by available carbohydrates (source strength). Alongside the observation that light supplementation and branching exert independent additive effects on fruit size and chemical traits, this illuminates the potential to independently regulate these aspects in greenhouse tomato production.
Authors
Thiago InagakiAbstract
The Norwegian Institute of Bioeconomy Research (NIBIO) has been working on many fronts to promote sustainable agriculture. As part of the Department of Biogeochemistry and Soil Quality, I will present initiatives and progress made by the NIBIO Institute in promoting soil organic matter persistence and sustainable agriculture in Norway and worldwide. Two major challenges have been targeted with a focus on Norway: waste generation by several industries (e.g., agriculture, forestry, and fishery) and the short time of the cropping season in the country due to climatic constraints. To solve these issues, we are working on several projects focused on re-utilizing waste products by producing organic fertilizers, optimizing these fertilizers (e.g., biochar N-enrichment), and improving current cropping systems with crop diversification. Our main objective is to investigate the benefits of these practices in improving soil quality and crop productivity and enhancing soil organic matter persistence. Our work on soil science also goes beyond Norwegian and Nordic conditions. Among our international collaborations, we are currently working on a multi-institution bilateral project between China and Norway to promote the restoration of a semi-arid ecosystem in Inner Mongolia. We are also often engaging in project proposals for promoting sustainable agriculture in tropical regions. To develop these ideas, we promote a combined approach of spectroscopy techniques in collaboration with other institutions, such as nanoscale secondary ion mass spectrometry (NanoSIMS) in partnership with the Technical University of Munich (TUM) and NMR spectroscopy in partnership with the National Research Council of Italy (CNR-Pisa). Also, our research facilities count on good infrastructure, focusing on incubations with 13C and 15N labeled amendments and 13C pulse labeling.
Authors
Arne BardalenAbstract
No abstract has been registered
Authors
Arne Stensvand Nan-Yi Wang Vinh Hong Le Claudio Dias Da Silva Jr Belachew Asalf Tadesse Chloé Grieu William W. Turechek Natalia A. PeresAbstract
Powdery mildew, caused by the ascomycete Podosphaera aphanis, is an important disease of strawberry. A slightly modified version of a method using steam thermotherapy to rid diseases and pests from strawberry transplants was tested against strawberry powdery mildew. Experiments took place in Norway and Florida, with potted strawberry plants heavily infected with the fungus. Aerated steam treatments of the plants were carried out as follows: a pre-treatment with steaming at 37 °C for 1 h was followed by 1 h at ambient temperature before plants were exposed to steaming at 40, 42, or 44 °C for 2 or 4 h in Norway and 44 °C for 4 h in Florida. Following steaming, plants from the different treatments and the untreated control were kept apart and protected from outside contamination of powdery mildew by growing them in closed containers with over-pressure. On steamed plants, hyphae of P. aphanis were dead and without any new spore formation after treatments, independent of temperature or exposure time; however, up to 99% of the area infected with powdery mildew prior to treatments contained actively sporulating lesions on non-steamed plants. None of the new leaves formed after steaming had powdery mildew, whereas more than half of the new leaves on non-treated plants were infected by P. aphanis. This investigation clearly indicates that steam thermotherapy can eradicate powdery mildew from strawberry transplants, and this can be achieved at lower temperatures and exposure times than previously reported for other pathogens.
Authors
Mirella Ludwiczewska Paulina Paluchowska Marta Janiszewska Erik Lysøe Simeon Rossmann Sylwester Sobkowiak Zhimin Yin May Bente Brurberg Jadwiga ŚliwkaAbstract
No abstract has been registered
Authors
Mirella Ludwiczewska Paulina Paluchowska Marta Janiszewska Erik Lysøe Simeon Rossmann Sylwester Sobkowiak Zhimin Yin May Bente Brurberg jadwiga SliwkaAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Junbin Zhao Mikhail Mastepanov Cornelya Klutsch Hanna Marika Silvennoinen Erling Fjelldal David Kniha Runar KjærAbstract
No abstract has been registered
Authors
Mohammad Tirgariseraji Tomas Persson Yaghoob Jafari Mahmood Sabouhi Sabouni Alisher Mirzabaev Alireza Nikouei Naser Shahnoushi ForoushaniAbstract
Negative environmental impacts of nitrogen (N) intensive diets have triggered global debates on sustainable nitrogen management. Solutions such as dietary transitions, cropland reallocation and N Regulatory Policy (NRP) have been proposed to mitigate the adverse environmental impacts of N use in food production. However, there is still insufficient understanding of how NRPs could be designed to minimize negative environmental impact across diverse agro-ecological zones without sacrificing human dietary requirements. To increase this understanding, we evaluated the consequences of three NRP scenarios (low, moderate, and high N fertilizer rates) on the amount of livestock and non-livestock diet components as well as the associated N leaching and farmers' Gross Margin (GM) by optimizing the allocation of cropland between food and feed crops. We developed a bio-economic Interval Fuzzy Multi-Objective Programming (bio-economic IFMOP) model for the Zayandeh-Rud river basin, Iran, and a procedure that accounts for annual average availability of calories per capita, calorie sources from livestock and non-livestock components of three dietary preferences, and inequality in calorie distribution. The interaction among soil, climate and weather variability and NRPs across nine sub-regions of the case study region was handled by crop yield simulation using the DSSAT software. The solution of farmers' GM, derived from the optimization problem across possibilities of water fluctuations, was assessed to determine the uncertainty in GM. We also introduced an N leaching per Block of Distributed Calories (BDC) criterion based on solutions of supplied calories and associated N leaching. The upper bound of the moderate NRP scenario resulted in the smallest N leaching per BDC. This corresponded to ∼0.34, ∼0.34, ∼3.77 and 19.00 million BDC of meat, dairy, wheat and potato, respectively. Also, the upper bound of this scenario satisfied the lowest instability in farmers’ GM against water fluctuation compared with low and high NRP scenarios. The affordable volume of N leaching per BDC varied across sub-regions between [1.53,3.49], [1.52,3.33], [0.76,0.99] and [0.05,0.08] kg for meat, dairy, wheat and potato, respectively. Our results highlighted both optimistic and pessimistic prospects of producing low N leaching diets. The approach of this study could also be applied to other regions and countries.
Abstract
No abstract has been registered