Agricultural and Food Science

First observations of Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) suggest that it is a transient species in Finland

2023-09-07T10:38:22+03:00

Drosophila suzukii, known as the spotted wing drosophila (SWD), is a major pest of berries and stone fruits. In 2014 it was recorded for the first time in the Nordic countries. In this study, we report the first observations of D. suzukii in Finland. The first trap catches of SWD were observed in 2019 in North Savo at a berry farm that handles imported berries. In 2020–2021, no adult flies were trapped at or near the farm, but in August 2022, adult SWDs were caught at the same farm. In 2023, one female of the same haplotype as the flies in previous year was found in mid July, but no further population growth was observed. This suggests that some overwintering events may happen, but lack of overwintered males may hinder the population growth. In 2021–2022, larvae and eggs of SWD were found in several batches of imported berries. Our results suggest that there is a pathway of introduction for SWD up to the farm level. Observed SWD adults in 2022 probably originated from a new introduction rather than an overwintered population, because no SWDs were observed during the two preceding seasons. Identification of D. suzukii specimens was confirmed with PCR and sequencing of the COI region, and four SWD haplotypes were found.

National-scale nitrogen loading from the Finnish agricultural fields has decreased since the 1990s

2023-06-22T17:19:31+03:00

The national scale nutrient load modelling system VEMALA-ICECREAM was used to simulate agricultural total nitrogen
(TN) loading and its trends for all Finnish watersheds for the period from 1990–2019. Across Finland, agricultural TN loading (ATNL) has decreased from 17.4 kg ha^-1 a-1 to 14.4 kg ha^-1 a^-1 (moving 10-year averages) since the 1990s. The main driver of the decrease in simulated ATNL is a reduction in mineral fertilizer use, which has decreased the N surplus in the soils. The TN leached fraction, however, did not show a trend but did have high annual variability due to variations in runoff; this corresponds to an average of 14.4% of the TN applied. The ATNL was considerably higher in the Archipelago Sea catchment compared to other Finnish Baltic Sea sub-catchments, with the lowest ATNL found in the Vuoksi catchment in Eastern Finland. The highest decrease of ATNL was simulated for Vuoksi and Gulf of Finland catchments. In the Bothnian Sea, Bothnian Bay and Archipelago Sea catchments, the decreasing trend of ATNL was smaller but still significant, with the exception of the Quark catchment, where there was no significant change. The differences in decreasing trends between regions can be explained by the heterogeneity of catchment characteristics, hydrology and agricultural practices in different regions.

Greenhouse gas and reactive N-gas emissions from a horse paddock – relationship to physicochemical properties of soil

2023-08-01T13:46:25+03:00

The horse industry today in Europe is an increasing leisure or sporting activity. Due to considerable input of nutrients
via dung and urine, horse paddocks can be significant sources of greenhouse gases (GHG) and reactive nitrogen (N)-gases. However, horse paddocks have not been studied intensively in contrast to e.g., dairy cow pastures. Here we report GHG emissions from one selected horse paddock in Eastern Finland. During the first year, GHG emissions from the site and surrounding grassland area were measured with closed static chamber method. In the following year soil samples were taken from the sites to study GHG emission and reactive N-gas (nitrous acid and nitric oxide) emissions in the laboratory. The paddock area emitted significant amounts of N-gases and methane compared with surrounding areas during wet season. N-gas emissions also increased with increasing soil mineral N concentration. We conclude that horse paddocks can be significant but local sources of greenhouse gases and wet soil conditions should be avoided to mitigate the emissions.

Long-term effects of liming on crop yield, plant diseases, soil structure and risk of phosphorus leaching

2023-08-30T06:58:56+03:00

This study examined the long-term effects of applying structure lime (mixture of ~80% CaCO₃ and 20% Ca(OH)₂) and ground limestone (CaCO₃) on soil aggregate stability and risk of phosphorus (P) losses 5–7 years after liming, incidence of soil-borne diseases and yield in winter wheat (Tritium aestivum), oilseed rape (Brassica napus) and sugar beet (Beta vulgaris). Lime was applied in 13 field trials in Sweden 2013–2015 and soil characteristics and crop yield were monitored until 2021. Seedbed (0–4 cm depth) aggregate (2–5 mm size) stability was improved to the same extent with both lime treatments compared to the untreated control, sampled 5–7 years after liming. Analyses and estimations of different P fractions (total P, PO₄-P, and particulate P) in leachate following simulated rainfall events on undisturbed topsoil cores sampled 6–8 years after liming revealed lower total P and particulate P concentrations in both lime treatments compared to the untreated control. Two sugar beet trial sites with soil pH ≤7.2 before liming showed an increase in sugar yield for structure lime and ground limestone as an effect of increased concentration of soil potassium (K-AL) and/or lower Aphanomyces root rot potential compared to the untreated control. The yield of winter wheat was not affected by the application of either type of lime at sites with pH >7.2 but the yield of oilseed rape decreased after the application of structure lime.

The in vitro digestates from Brussels sprouts processed with various hydrothermal treatments affect the intestinal epithelial cell differentiation, mitochondrial polarization and glutathione level

2023-07-11T09:44:55+03:00

Brussels sprouts provide bioactive compounds with widely acknowledged health-promoting effects observed in various levels: single cells, organs and tissues, or the whole organism. However, the choice of the appropriate hydrothermal processing is critical to sustain the nutritional values and cytoprotective activities, as Brussels sprouts are rarely eaten raw. The aim of this study was to evaluate the impact of various culinary methods (boiling, steaming, and sous-vide in comparison to raw plant material) applied to Brussels sprouts on the chosen functions of liver and intestinal cell lines (HepG2 and Caco-2, respectively): the markers of enterocyte differentiation (alkaline phosphatase and sucrase-isomaltase activities and protein level), glutathione store management (total GSH concentration and Glu, Gly, Cys and Met amino acids analysis) and mitochondrial polarization (JC-1 staining analysis). The in vitro digestates from raw Brussels sprouts had a stronger positive effect on the enterocyte marker enzymes in the Caco-2 cultures as compared to the digestates from the hydrothermally processed vegetables (boiled, steamed, and sous-vide). The sous-vide method diminished the intracellular glutathione stores. Hydrothermal processing, particularly steaming and sous-vide had a negative impact on the mitochondrial abundance and polarization as compared to raw vegetables. Our results suggest that shorter processing is more beneficial to retain glutathione and mitochondrial polarization than longer hydrothermal treatment.

Collective agency as a leverage point in multi-actor innovation

2023-07-31T07:24:01+03:00

The aim of this study is to investigate how horticultural firms meet their need for innovation within the innovation system. A comparative process ethnography approach was applied to two cases of long-term collaboration between multiple actors in Swedish horticulture. The retrospective reconstruction of the cases through documentation and interviews allowed for triangulation of data in a grounded theory approach. The leverage points of the developing collaborative processes were found to be; having agency and a network approach, the forming of collective agency through social learning, enhancing resource access, and operationalization of results. The concept of leverage points is useful for understanding evolutionary changes in multi-actor collaborations. The use of the concept of collective agency contributes to the understanding of the dynamics of demand articulation, illustrating a reciprocal process between the actors’ individual agencies, and evolving over time through their social learning. The results point to a need for policymakers and practitioners to develop a broader understanding of how actors work in the innovation system to enhance knowledge development and innovation.