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Putative neural and endocrine control of thermal acclimation in fish

Leeuwis, Robine H J; Morgan, Rachael; Andreassen, Anna H; Silva-Garay, Lorena; Cowan, Zara-Louise; Åsheim, Eirik R; De Bonville, Jeremy; Binning, Sandra A; Raby, Graham D; Jutfelt, Fredrik
Conservation physiology : 1 (Oxford University Press, 2025)

Fishes can acclimate to a range of temperatures. However, the signalling factors controlling thermal acclimation are not well understood. Here, in two experiments, we examined the putative roles of plasma-borne factors (e.g. hormones) and skin thermoreception in the acclimation process. In experiment 1, 16°C-acclimated Atlantic cod (Gadus morhua) were subjected to a transfusion treatment by injecting plasma from 8°C (cold), 16°C (control) or 21°C (warm) acclimated cod, 10 times over four days. Plasma was collected from donor cod that were 24 h into their acclimation. In experiment 2, 16°C-acclimated goldsinny wrasse (Ctenolabrus rupestris) were exposed to an immersion treatment consisting of 10 s immersions in an 8°C (cold), 16°C (control) or 24°C (warm) water bath, repeated five times daily for five days. These brief immersions allowed for changes to skin temperature but not deeper tissues. Following these treatments, we measured the critical thermal maximum (CTmax) of all fish and the standard metabolic rate (SMR) in cod. Neither the immersions nor transfusions affected fish CTmax. However, the SMR was elevated in cod receiving plasma from cold-acclimated donors, suggesting that circulating molecules transferred from donors had initiated metabolic compensation in recipients. Thyroid hormone plasma levels were not different amongst acclimated donors and thus appear not to have been involved in the metabolic compensation. Our experiments found no evidence that brief, repeated cutaneous exposures to temperature changes can trigger acclimation, but do demonstrate a potential role of haematological endocrine control in metabolic acclimation, although further experiments will be required to investigate this process.

Improving governance arrangements for vegetable value chains in sub-Saharan Africa: the case of Bahir Dar, Ethiopia and Cotonou, Benin

Isoto, Rosemary Emegu; Turinawe, Alice; Nakamatte, Irene; Sumelius, John; Chen, Qiuzhen; Prosperi, Paolo; Sell, Mila; Bodjrenou, Fifali Sam Ulrich; Koukou, Elie; Bello, Faïck; Amoussa Hounkpatin, Waliou; Alemayehu, Melkamu; Desta, Gashaw Tilahun; Assaye, Hirut; Adgo, Enyew; Bankole, Bissola Malikath
International food and agribusiness management review : 1 (International Food and Agribusiness Management Association, 2025)

Improved governance arrangements are central in strengthening value chains with sustainable, resilient farming and healthy nutrition. This study explored governance arrangements important to the vegetable value chains in Food System Labs in Bahir Dar (Ethiopia) and Cotonou (Benin). The study collected data through face-to-face interviews from different actors including input suppliers, producers, processors, wholesalers, retailers and from different supporting institutions such as credit organizations in the vegetable value chains in the two regions. The paper uses descriptive analysis for quantitative data, content analysis for qualitative data, and the strengths, weaknesses, opportunities, and threats (SWOT) analysis method in the context of the indicator-based assessment framework to examine governance arrangements. Results indicate that multiple but also alternating modes of governance arrangements exist along the vegetables value chain. Spot market relations dominate at the successive stages of the value chain where different actors randomly interact at every transaction. Relational governance in terms of information sharing is notable among producers who attach high relevance to farmer associations as well as traders who largely trust and source information from amongst themselves. The value chains are typical of limited collaboration between actors coupled with weak processing skills. In addition, unconducive storage facilities undermine the potential of upgrading despite changing preferences and growing demand for vegetables. The study recommends development and strengthening of actor organizations such as cooperatives and associations, provision of an enabling environment where vegetable value chains can thrive, and national level efforts to develop post-harvest handling skills and infrastructure, as well as exploitation of last mile digitization initiatives to increase competitiveness of vegetable trade.

Substituting fossil-based mineral fertilizers with bio-based products - impacts on potentially toxic elements in soil and crops

Salo, Tapio; Keskinen, Riikka; Del Rosario Dominguez Carrasco, Maria; Suomi, Johanna; Ylivainio, Kari
Agricultural and food science : 3 (Scientific Agricultural Society of Finland, 2025)

Similar to conventional mineral fertilizers, circular bio-based fertilizer (BBF) products may contain potentially toxic elements (PTEs). In this study, conducted as part of the LEX4BIO project, the contents of arsenic (As), cadmium (Cd), nickel (Ni) and lead (Pb) were surveyed in 37 phosphorus (P) BBFs and 7 nitrogen (N) BBFs representing different product function and component material categories. In addition, mass balances of these elements were calculated over 100-year scenarios of P fertilization with a product that was low or high in the assessed elements, a common mineral phosphate fertilizer (MPF), and a hypothetical fertilizer containing the maximum amount of these PTEs allowed by the EU regulations. The examination was performed using case-specific conditions for Finland, Denmark, France, Spain, Hungary, and Germany, in which countries the products had been tested. Although in some individual products the current maximum EU limits were exceeded for Cd and Ni, the contents of the targeted PTEs were overall low in the studied products. The dominant trends in the contents and fluxes of As, Ni, and Pb were decreasing in all fertilizer-use scenarios with observed BBF concentrations, but the maximum allowed rates would instead commonly lead to prominent increases. The highest sensitivity to variation in fertilizer input rates, along with some substantial increases in the environmental contents and fluxes was observed for Cd. However, with low-Cd BBFs, favorable development is also achievable for Cd fluxes. It is recommended that PTE levels remain well below the maximum EU limits.

Experimental species introductions influence fungal community succession through positive and negative effects on resident species

Saine, Sonja Karoliina; Fukami, Tadashi; Penttilä, Reijo; Furneaux, Brendan; Ovaskainen, Otso Tapio; Abrego Antia, Nerea
ISME communications : 1 (Oxford University Press, 2025)

Successional pathways of microbial communities are influenced by the complex interactive dynamics among the resident and immigrating species, along with the interactive feedback loops with their environment. Although studies on microbial communities have described patterns of microbial succession, quantitative evidence of how resident communities respond to immigrating species and how such relationships translate into successional changes remains limited, especially for species-rich communities under natural settings. Here, we carried out a field experiment to investigate how the identity of immigrating species influences the successional pathways of wood-inhabiting fungi. We simulated immigration through inoculations of nine selected wood-inhabiting fungal species and characterized resident fungal communities before and one and two years after the inoculations through DNA metabarcoding. The experiments included 275 naturally fallen and 185 artificially felled fresh logs of Norway spruce, with different log types hosting distinct initial resident communities of fungi and representing different abiotic conditions. While the resident community succession was mostly explained by the log-level abiotic characteristics, the identity of immigrating species also influenced the composition of resident communities, and consequently community succession. The immigrating species influenced resident species mostly negatively, suggesting competitive interactions to be important determinants of community succession. The responses of resident species to the immigrating species were phylogenetically correlated, suggesting that shared traits underlie species interactions in the species-rich wood-inhabiting fungal communities. This study advanced the understanding of community succession in species-rich natural systems by providing experimental evidence that the immigrating species influence community succession through the phylogenetically structured responses of resident species.

Determining the carbon transport time from Scots pine (Pinus sylvestris L.) needles to ectomycorrhizal sporocarps using the natural abundance carbon isotopic composition

Mo, Lan; Salmon, Yann; Lehmann, Marco M.; Hobbie, Erik A.; Schiestl-Aalto, Pauliina; Sahlstedt, Elina; Tang, Yu; Bienz, Siiri; Young, Giles H.F.; Rinne‐Garmston , Katja T.
Tree physiology : 12 (Oxford University Press, 2025)

Ectomycorrhizal (ECM) fungi, as major carbon (C) sinks, are critical to plant–soil C cycling. Although C allocation between plants and ECM fungi has been studied extensively, C transport time, the key component of C cycling, remains poorly understood. To address this, we collected new needles (weekly), roots (monthly) and ECM fungi (sporocarps and hyphae) of three genera (Cortinarius, Lactarius and Russula) in a boreal Scots pine (Pinus sylvestris L.) forest in Finland. We analysed the natural abundance C isotope composition (δ13C) of sugars or organic matter and observed a strong vapour pressure deficit (VPD) signal in needle sucrose δ13C. We coupled VPD with the δ13C of water-soluble carbohydrates (WSC, δ13CWSC) in sporocarps to determine C transport times. We found Lactarius and Russula, with short hydrophilic mycelia that enable efficient solute uptake, had transport times of 6–13 days, peaking at 8 days. In contrast, Cortinarius, with extensive hydrophobic mycelia that limit water and solute movement, showed slower transport times of around 18 days. The different transport time is likely attributable to a more extensive mycelial network and potentially higher C demand in Cortinarius compared with Lactarius and Russula. The three genera also showed a marginally significant effect on δ13CWSC in sporocarps (P = 0.06, analysis of covariant). This study highlights that natural abundance δ13C analysis offers a practical alternative to pulse-labelling for estimating C transport time in complex plant–fungal interactions, where the latter is difficult to implement. The longer transport time of Cortinarius compared with Lactarius and Russula is critical during periods of reduced photosynthesis, when limited C supply makes fast allocation essential for sustaining belowground metabolism. Slower transport may weaken its role and reduce forest productivity in boreal forests with short growing seasons. As global warming favours Cortinarius, its longer C transport time may impede soil C cycling and nutrient turnover.