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Tervetuloa käyttämään Jukuria, Luonnonvarakeskuksen (Luke) avointa julkaisuarkistoa. Jukurissa on tiedot Luken julkaisutuotannosta. Osa julkaisuista on vapaasti ladattavissa. Luken muodostaneiden tutkimuslaitosten aikaisemmasta julkaisutuotannosta osan tiedot ovat järjestelmässä jo nyt ja kattavuus paranee jatkuvasti.

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Viimeksi tallennetut

Photosynthetic Adjustments Maintain Lettuce Growth Under Dynamically Changing Lighting in Controlled Indoor Farming Setups
Mäkinen, Arttu; Ishihara, Hirofumi; Poque, Sylvain; Sipari, Nina; Himanen, Kristiina; Varjus, Ilona; Heininen, Juho; Pastell, Matti; Elomaa, Paula; Shapiguzov, Alexey; Kotilainen, Titta; Kangasjärvi, Saijaliisa
Physiologia plantarum : 4 (Wiley-Blackwell, 2025)
Studies have uncovered delicate mechanisms that enable plant acclimation to fluctuating light. Translating the knowledge to controlled environment agriculture could advance the development of cost-effective dynamic lighting strategies where the light intensity is purposely alternated, mirroring the spot electricity price, but its effects on vegetable crops remain poorly understood. Here, we recorded photosynthetic parameters, metabolic responses, and growth of lettuce (Lactuca sativa L.) cv. “Katusa” under dynamic lighting. The light intensity was altered at different times of the photoperiod with uniform daily light integral. Three different setups, including a plant phenotyping facility, a small-scale vertical farm testbed and a larger-scale vertical farm, were utilized to address the physiological responses and scalability of lighting strategies. The lettuces readily adjusted their photosynthetic light reactions and carbon metabolism according to the changing light intensities. However, the overall metabolic composition of lettuce leaves did not respond to dynamic lighting. Upon simulation of commercial production in the larger-scale vertical farm, constant and dynamic lighting regimes yielded lettuce heads with equal saleable sizes of 87–89 g, even under artificial “Split-Night” regimes where the photoperiod was interrupted by two periods of darkness. These findings suggest that dynamic lighting strategies enable cost-effective lighting via optimization of electricity use in indoor cultivation.
Protection of Photosynthesis by UVR8 and Cryptochromes in Arabidopsis Under Blue and UV Radiation
Morales, Luis Orlando; Shapiguzov, Alexey; Rai, Neha; Aphalo, Pedro José; Brosché, Mikael
Plant cell and environment : 8 (John Wiley & Sons, 2025)
Photosynthesis in plants is negatively affected by high light intensity and UV radiation. The photoreceptors UV RESISTANCE LOCUS 8 (UVR8) and CRYPTOCHROMES (CRYs) mediate perception and acclimation of plants to UV-B/UV-A2 (290–340 nm) and UV-A1/blue light (350–500 nm), respectively. However, their roles in photoprotection of photosynthesis across different wavebands of the spectrum remain unclear. Using chlorophyll fluorescence and LED lighting we studied the roles of UVR8 and CRYs in maintaining photosynthetic capacity in Arabidopsis exposed to UV-B, UV-A1, and blue light. Analysis of quantum yield of Photosystem II, nonphotochemical quenching, and LHCII phosphorylation demonstrated that CRYs preserve photosynthetic performance in plants exposed to UV-B, UV-A1, and blue light. UVR8 and CRYs exhibit partially redundant functions in maintaining photosynthetic activity under UV-B, UV-A1, and blue light, and in preventing photodamage under high UV-A1 irradiance. Impaired UVR8 and CRY signalling reduced epidermal flavonol accumulation in leaves, which further compromised photoprotection. These findings provide valuable insights into how UV and blue light perception contribute to photoprotection, with broad implications for plant performance both in natural and managed environments.
Nitrogen fertilisation of boreal forest soil increases soil carbon pool through elevated microbial necromass formation but also modifies tree secondary metabolism
Adamczyk, Bartosz; Adamczyk, Sylwia; Tupek, Boris; Li, Qian; Martinovic, Tijana; Richy, Etienne; Lehtonen, Aleksi; Baldrian, Petr; Mäkipää, Raisa
Soil biology and biochemistry (Elsevier, 2025)
Forests contain significant amounts of the global carbon (C) pool with the major fraction stored belowground. Nitrogen (N) fertilisation of forest soils may increase biomass production and soil organic C pools, providing a strategy for climate change mitigation. Here we aimed to elucidate the mechanisms behind the increase in soil C due to N addition using a long–term fertilisation experiment on a Scots pine stand with a combination of chemistry, microbiology and greenhouse gas fluxes. Our results showed that N fertilisation increased C stocks, microbial biomass, necromass and the activity of extracellular enzymes, with no significant increase in greenhouse gas production. Moreover, N fertilisation decreased the production of a group of plant secondary metabolites, tannins. These profound changes were observed in the organic layer of the soil, and differences in mineral soil were less detectable. Mechanistically, N fertilisation increased the C stock via elevated litter input and higher transfer of root C to soil microorganisms increasing fungal biomass and further necromass, which was stabilised in the soil. Our study supports the view that management strategies to increase microbial necromass in persistent C pools could lead to elevated C stabilization, though caution should be taken regarding potential changes in plant metabolism.
Trophic interactions and microbial-derived carbon in porosphere of arable fields
Salminen, Janne; Hyväluoma, Jari; Adamczyk, Bartosz; Adamczyk, Sylwia; Niemi, Petri; Kinnunen, Sami; Miettinen, Arttu
Soil biology and biochemistry (Elsevier, 2025)
Soil physical properties, such as porosity, are recognized to play an important role in the formation of soil organism communities and may regulate carbon sequestration in the soil ecosystem. However, despite their eminent importance, the relation between the abundance of soil animals, microbial necromass and pore space has been rarely demonstrated empirically. In this study, soil visible macroporosity (measured using X-ray computed tomography), microbial necromass (a pool of soil organic carbon), and densities of nematode groups were measured in the topsoil layer at a depth of 10 cm in four arable fields in southern Finland (clay and loam soils). Bacterial necromass was positively correlated with visible macroporosity smaller than 428 μm in size. Fungal necromass was marginally correlated (p = 0.059) with pores <233 μm in size. The abundance of bacterial feeding nematodes (and unknown juveniles) scaled positively with microbial necromasses, visible macropores smaller than 700 μm and the total visible macroporosity. The abundance of other feeding groups was independent of soil visible macroporosity. However, trophic interactions between feeding groups of nematodes appeared to be weak in this soil layer. Results indicate strong bottom-up regulation between microbes and microbial feeding nematodes. Microbial necromass, as an important organic fraction in soil, was clearly related to small soil macropores (<428 μm). These findings provide novel insights into how soil architecture, particularly macroporosity below 700 μm, influences the spatial ecology of soil organisms - an aspect that has received limited attention in boreal agroecosystems.
Chromosome-Level Assemblies of Three Candidatus Liberibacter solanacearum Vectors: Dyspersa apicalis (Förster, 1848), Dyspersa pallida (Burckhardt, 1986), and Trioza urticae (Linnaeus, 1758) (Hemiptera: Psylloidea)
Heaven, Thomas; Mathers, Thomas C; Mugford, Sam T; Jordan, Anna; Lethmayer, Christa; Nissinen, Anne I; Høgetveit, Lars-Arne; Highet, Fiona; Soria-Carrasco, Victor; Sumner-Kalkun, Jason; Goldberg, Jay K; Hogenhout, Saskia A
Genome biology and evolution : 6 (Oxford University Press, 2025)
Psyllids are major vectors of plant diseases, including Candidatus Liberibacter solanacearum (CLso), the bacterial agent associated with “zebra chip” disease in potatoes and “carrot yellows” disease in carrot. Despite their agricultural significance, there is limited knowledge on the genome structure and genetic diversity of psyllids. In this study, we provide chromosome-level genome assemblies for three psyllid species known to transmit CLso: Dyspersa apicalis (carrot psyllid), Dyspersa pallida, and Trioza urticae (nettle psyllid). As D. apicalis is recognized as the primary vector of CLso by carrot growers in Northern Europe, we also resequenced populations of this species from Finland, Norway, and Austria. Genome assemblies were constructed using PacBio HiFi and Hi–C sequencing data, yielding genome sizes of 594.01 Mbp for D. apicalis; 587.80 Mbp for D. pallida; and 655.58 Mbp for T. urticae. Over 90% of sequences anchored into 13 pseudo-chromosomes per species. D. apicalis and D. pallida assemblies exhibited high completeness, capturing over 92% of conserved Hemiptera single-copy orthologs. Furthermore, we identified sequences of the primary psyllid symbiont, Candidatus Carsonella ruddii, in all three species. Gene annotations were produced for each assembly: 17,932 unique protein-coding genes were predicted for D. apicalis; 18,292 for D. pallida; and 16,007 for T. urticae. We observed significant expansions in gene families, particularly those linked to potential insecticide detoxification, within the Dyspersa lineage. Resequencing also revealed the existence of multiple subpopulations of D. apicalis across Europe. These high-quality genome resources will support future research on genome evolution, insect–plant–pest interactions, and disease management strategies.