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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.

2024

Sammendrag

BACKGROUND As regulations on pesticides become more stringent, it is likely that there will be interest in steam as an alternative approach for soil disinfestation. This study investigates the feasibility of utilizing a soil steaming device for thermal control of invasive plants. RESULTS Seeds of Echinochloa crus-galli, Impatiens glandulifera, Solidago canadensis, and rhizome fragments of Reynoutria × bohemica were examined for thermal sensitivity through two exposure methods: (1) steam treatment of propagative material in soil; (2) exposure of propagative material to warm soil just after heated by steam. Soil temperatures in the range of 60–99 °C and dwelling period of 3 min were tested. Increased soil temperature decreased seed germination/rhizome sprouting. The exposure method had a significant effect where higher temperatures were needed to reduce the seed germination/rhizome sprouting in method 2 explained by the effect of extra heat given in method 1. Using method 1, for E. crus-galli and S. canadensis, the maximum mean temperature of approximately 80 °C was enough to achieve the effective weed control level (90%). This was lower for I. glandulifera and higher for R. × bohemica. Using method 2, 90% control was achieved at 95 °C for S. canadensis; more than 115 °C for I. glandulifera; and more than 130 °C for E. crus-galli and R. × bohemica. CONCLUSION Our findings showed a promising mortality rate for weeds propagative materials through soil steaming. However, the species showed varying responses to heat and therefore steam regulation should be based on the differences in weeds' susceptibility to heat.

Sammendrag

Gray mold, caused by Botrytis spp., is a serious problem in Norway spruce seedling production in forest nurseries. From 2013 to 2019, 125 isolates of Botrytis were obtained from eight forest nurseries in Norway: 53 from Norway spruce seedlings, 16 from indoor air, 52 from indoor surfaces, and four from weeds growing close to seedlings. The majority of isolates were identified as B. cinerea, and over 60% of these were characterized as Botrytis group S. B. pseudocinerea isolates were obtained along with isolates with DNA sequence similarities to B. prunorum. Fungicide resistance was assessed with a mycelial growth assay, and resistance was found for the following: boscalid (8.8%), fenhexamid (33.6%), fludioxonil (17.6%), pyraclostrobin (36.0%), pyrimethanil (13.6%), and thiophanate-methyl (50.4%). Many isolates (38.4%) were resistant to two to six different fungicides. A selection of isolates was analyzed for the presence of known resistance-conferring mutations in the cytb, erg27, mrr1, sdhB, and tubA genes, and mutations leading to G143A, F412S, ΔL497, H272R, and E198A/F200Y were detected, respectively. Detection of fungicide resistance in Botrytis from Norway spruce and forest nursery facilities reinforces the necessity of employing resistance management strategies to improve control and delay development of fungicide resistance in the gray mold pathogens.

Sammendrag

Carbon content is a key property of soils with importance for all ecosystem functions. Measures to increase soil carbon storage are suggested with the aim to compensate for agricultural emissions. In Norway, where soils have relatively high carbon content because of the cold climate, adapting management practices that prevent the loss of carbon to the atmosphere in response to climate change is also important. This work presents an overview of the potential for carbon sequestration in Norway from a wide range of agricultural management practices and provides recommendations based on certainty in the reported potential, availability of the technology, and likelihood for implementation by farmers. In light of the high priority assigned to increased food production and degree of self-sufficiency in Norway, the following measures were considered: (1) utilization of organic resources, (2) use of biochar, (3) crop diversification and the use of cover crops, (4) use of plants with larger and deeper root systems, (5) improved management of meadows, (6) adaptive grazing of productive grasslands (7) managing grazing in extensive grasslands, (8) altered tillage practices, and (9) inversion of cultivated peat with mineral soil. From the options assessed, the use of cover crops scored well on all criteria evaluated, with a higher sequestration potential than previously estimated (0.2 Mt CO2-equivalents annually). Biochar has the largest potential in Norway (0.9 Mt CO2-equivalents annually, corresponding to 20% of Norwegian agricultural emissions and 2% of total national emissions), but its readiness level is not yet achieved despite interest from industry to apply this technology at large scale. Extensive grazing and the use of deep-rooted plants also have the potential for increasing carbon storage, but there is uncertainty regarding their implementation and the quantification of effects from adapting these measures. Based on the complexities of implementation and the expected impacts within a Norwegian context, promising options with substantial payoff are few. This work sheds light on the knowledge gaps remaining before the presented measures can be implemented.

2023