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.
2024
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No abstract has been registered
Abstract
Since the 1950s, the use of plastics in agriculture has helped solving many challenges related to food production, while its persistence and mismanagement has led to the plastic pollution we face today. Soils are no exception and concentrations of polyethylene mulch debris up to 380 kg/ha have been reported in Chinese agricultural soils. A variety of biodegradable plastic products have thus been developed and marketed, with the aim to solve plastic pollution through complete degradation after use. But the environmental conditions for rapid and complete degradation are not always fulfilled, and the risk that biodegradable plastics could also contribute to plastic pollution must be evaluated. In this presentation, we want to share the knowledge gained through research projects on biodegradable plastics in agricultural soil, where we both studied the degradation of biodegradable mulch under Nordic soil conditions, and the fate of biodegradable plastics in two major soil amendments: compost and biogas digestate. A two-year field experiment with biodegradable mulch (PBAT-starch and PBAT-PLA) buried in soil in mesh bags showed that also under colder climatic conditions does degradation occur, involving fragmentation already after 2 months, but that complete degradation may take 3 to 9 years, depending on soil temperature and soil organic matter content (both correlate positively with degradation rate). Accumulation is therefore likely to happen when biodegradable mulch is repeatedly used every year. A full-scale experiment with compostable plastic cups (PLA) at an industrial composting plant, where we followed their fate and conducted metagenomic analysis over 13 weeks, demonstrated the major role played by fungi for a successful degradation of PLA. However, the successful management of biodegradable plastic products largely depends on existing waste management infrastructure. Most biodegradable plastic bags, labelled as compostable and used for food waste collection do not end up in industrial composting plants in Norway, but in biogas production plants. Here, we showed that these plastic bags (starch-based polymer) are only marginally degraded (maximum 21-33 % mass loss) during biogas production, and likely to end up in biogas digestate and then in agricultural soils, unless digestate is treated to remove plastic residues.
Authors
Claire Coutris Karl Andreas Jensen Pierre-Adrien Rivier Selena Deviller Anastasia Georgantzopoulou Sebastian KuehrAbstract
By the time they enter soils, engineered nanomaterials (ENM) have undergone physicochemical transformations and may no longer resemble the pristine materials which have been thoroughly investigated during two decades of nanotoxicology research. Is the behavior of environmentally relevant chemical forms of ENM different from that of other metallic species present in soils? Are they more available to soil organisms than their naturally occurring counterparts? The present study aimed at answering these questions, through the use of isotopically enriched ENMs, which could be traced at low concentrations in soil microcosms, despite high natural metallic background. The relevance of the chemical forms was ensured by introducing isotopically enriched 109Ag, 68ZnO and 46TiO2 ENM to a wastewater treatment plant and using the resulting sewage sludge (final sink for most ENM) as amendment in soil microcosms with earthworms. The sludge application rate to soil was similar to that used in agriculture and the experiment lasted for a month. Protocols using inductively coupled plasma mass spectrometry were developed for determination of isotope ratios in complex matrixes, such as soil and organisms. For 109Ag ENM, the dissolved fraction in soil (i.e. the most easily accumulated in organisms) was extremely low and comparable to that of Ag naturally present in soil, and transfer factors to earthworms were similar to those of natural Ag. For 46TiO2 ENM, the transfer to earthworms was negligible, similarly to what was observed for natural Ti. While no difference in behavior and bioavailability was observed between ENM and their naturally occurring counterparts for Ag and Ti, different results were obtained for Zn. The dissolved fraction for 68ZnO ENM was 3-5 times higher than for Zn forms naturally present in soil, and transfer factors to earthworms twice those of natural Zn. Overcoming long-standing challenges related to environmental relevance of chemical forms and concentrations in nanotechnology studies, the approach provides valuable insight into behavior and impacts of environmentally relevant forms of ENM in soils.
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No abstract has been registered
Authors
João Neiva Jorge Manuel Ferreira de Assis Eliza Fragkopoulou Gareth A. Pearson Peter T. Raimondi Laura Anderson Dorte Krause-Jensen Núria Marbà Andrew Want Olga Selivanova Masahiro Nakaoka W. Stewart Grant Brenda Konar Michael Roleda Mikael K. Sejr Cristina Paulino Ester A. SerrãoAbstract
No abstract has been registered
Abstract
Background The stink bugs, Nezara viridula L. and Piezodorus guildinii Westwood (Hemiptera: Pentatomidae) are the most important and widespread species of polyphagous stink bugs in the tropical and subtropical regions of Latin America, which affect the quality and yield of the common bean (Phaseolus vulgaris L.). The use of synthetic chemical insecticides is the major control strategy to manage stink bugs in common beans and alternatives are needed. In this study, mortality and median Lethal Time (LT50) of two Cuban isolates of the entomopathogenic fungus Beauveria bassiana (18 S-O-R and 96 P-O-E), as well as one commercial Cuban isolate (Bb-18), at a concentration of 1 × 108 conidia/ml were evaluated. These evaluations were conducted against both stink bug species using Petri dish bioassays and a semi-field experiment in common beans. Results In Petri dish bioassays, the isolates 18 S-O-R and 96 P-O-E caused 100% mortality of both N. viridula and P. guildinii. This was significantly higher than for isolate Bb-18, which caused 86.3% N. viridula and 81.3% P. guildinii mortality. In the semi-field experiment, when pooling both stink bug species, total mortality after 14 days was 91.3% for 18 S-O-R, 80.0% for 96 P-O-E and 73.8% for Bb-18 isolates. LT50 value for isolate 18 S-O-R tested under laboratory conditions was 6.04 ± 0.18 days for N. viridula and 5.32 ± 0.14 days for P. guildinii at the same concentration of 1 × 108 conidia/ml. LT50 value for isolate 18 S-O-R in semi field was 6.79 ± 0.37 days for N. viridula and 7.71 ± 0.32 days for P. guildinii at 1 × 108 conidia/ml. Conclusion The study highlights the potential of B. bassiana 18 S-O-R as a promising candidate for control of stink bugs in common bean under tropical conditions as an alternative to conventional chemical insecticides in integrated pest management (IPM) programs. Moving forward, further research should focus on validating the efficacy under diverse field conditions and integrating application methods into practical IPM approaches. Future use of B. bassiana will enhance sustainability and reduce environmental impacts associated with pesticide use. Keywords Nezara viridula, Piezodorus guildinii, Entomopathogenic fungi, Hypocreales, Biological control, Common bean
Authors
Mekjell Meland Oddmund Frøynes Milica Fotirić Akšić Naris Pojskić Belma Kalamujić Stroil Merima Miralem Almira Konjić Fuad GasiAbstract
No abstract has been registered
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No abstract has been registered
Authors
Anastasia Georgantzopoulou Sebastian Kühr Ralf Kaegi Mark Rehkämper Ralph A. Sperling Karl Andreas Jensen Ana Catarina Almeida Claire CoutrisAbstract
No abstract has been registered