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Povzetek: Beyond growth parameters and drought tolerance, comparatively little is known about the functioning of different beech (Fagus sylvatica L.) provenances. We investigated properties of leaves, stem secondary xylem, and ectomycorrhiza (ECM), and explored their interdependencies to identify the best performing beech provenance in optimal growth conditions. The study was conducted on 23-year-old trees in a provenance trial. The investigated provenances originated from Atlantic (Belgium—BE), Alpine (Italy—IT, Slovenia—SI), and continental climates (the Czech Republic—CZ). A significant effect of provenance was observed for stem vessel diameters and conductive area, as well as for foliar %C, δ13C, δ15N, and δ18O. δ13C as a proxy of intrinsic water use efficiency (iWUE) showed that the highest iWUE was achieved in BE provenance. Individuals with a better iWUE had wider growth rings regardless of provenance. Better iWUE was associated with lower specific leaf area (SLA). ECM community composition and diversity indices did not differ significantly among the provenances. Specific ECM taxa were associated with individuals with high SLA, δ13C, δ15N, and δ18O. In optimal growth conditions with no stress events, BE is a promising provenance due to an efficient water conducting system with high vessel diameters and conductive area, and high iWUE, while Alpine provenances showed an adaptation of their water conducting system to freezing conditions at their original locations. Integrating findings from different compartments improves our understanding of functioning of different beech provenances.
Ključne besede: Fagus sylvatica, provenance trial, stable isotopes, specific leaf area, xylem vessels, ectomycorrhizal fungi
Objavljeno v DiRROS: 19.04.2024; Ogledov: 30; Prenosov: 8
Celotno besedilo (2,11 MB)
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Povzetek: Soil contamination is one of the main threats to ecosystem health and sustainability. Yet little is known about the extent to which soil contaminants differ between urban greenspaces and natural ecosystems. Here we show that urban greenspaces and adjacent natural areas (i.e., natural/semi-natural ecosystems) shared similar levels of multiple soil contaminants (metal(loid)s, pesticides, microplastics, and antibiotic resistance genes) across the globe. We reveal that human influence explained many forms of soil contamination worldwide. Socio-economic factors were integral to explaining the occurrence of soil contaminants worldwide. We further show that increased levels of multiple soil contaminants were linked with changes in microbial traits including genes associated with environmental stress resistance, nutrient cycling, and pathogenesis. Taken together, our work demonstrates that human-driven soil contamination in nearby natural areas mirrors that in urban greenspaces globally, and highlights that soil contaminants have the potential to cause dire consequences for ecosystem sustainability and human wellbeing.
Ključne besede: soil contamination, urban greenspaces
Objavljeno v DiRROS: 28.03.2023; Ogledov: 586; Prenosov: 234
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Povzetek: The timing of leaf phenology tends to be crucial in controlling ecosystem processes such as the acquisition of carbon and water loss as well as in controlling tree nutrient cycling. To date, tree phenology has mostly been associated with environmental control (e.g., temperature and photoperiod) in a relationship with inheritance, while it has rarely been linked with ectomycorrhizal community compositional changes through the host tree’s phenological stages. Seasonal variations of fungal communities have been widely studied, but little is known about mycorrhiza community composition changes along phenological stages. Therefore, we analyzed ectomycorrhizal communities associated with silver fir and their compositional changes during the transition between phenological stages. The phenological stages of each individual tree and time of bud break were monitored weekly for two years and, at the same time, ectomycorrhiza was harvested from selected silver fir trees. In total, 60 soil cores were analyzed for differences in the ectomycorrhizal community between phenological stages using Sanger sequencing of individual ectomycorrhizal morphotypes. A significant difference in beta diversity for an overall ectomycorrhizal community was confirmed between analyzed time periods for both sampled years. Species-specific reactions to transitions between phenological stages were confirmed for 18 different ectomycorrhizal taxa, where a positive correlation of Russula ochroleuca, Russula illota, Tomentella sublilacina, and Tylospora fibrillosa was observed with the phenological stage of bud burst.
Ključne besede: Abies alba (Mill.), ectomycorrhizal community, phenological stages
Objavljeno v DiRROS: 20.12.2021; Ogledov: 765; Prenosov: 572
Celotno besedilo (1,73 MB)
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Povzetek: The structure and function of the soil microbiome of urban greenspaces remain largely undetermined. We conducted a global field survey in urban greenspaces and neighboring natural ecosystems across 56 cities from six continents, and found that urban soils are important hotspots for soil bacterial, protist and functional gene diversity, but support highly homogenized microbial communities worldwide. Urban greenspaces had a greater proportion of fast-growing bacteria, algae, amoebae, and fungal pathogens, but a lower proportion of ectomycorrhizal fungi than natural ecosystems. These urban ecosystems also showed higher proportions of genes associated with human pathogens, greenhouse gas emissions, faster nutrient cycling, and more intense abiotic stress than natural environments. City affluence, management practices, and climate were fundamental drivers of urban soil communities. Our work paves the way toward a more comprehensive global-scale perspective on urban greenspaces, which is integral to managing the health of these ecosystems and the well-being of human populations.
Ključne besede: soil biodiversity, structural diversity, functional diversity, urban soils
Objavljeno v DiRROS: 15.07.2021; Ogledov: 974; Prenosov: 824
Celotno besedilo (4,34 MB)
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Povzetek: Since late 20th century DNA sequencing became the method of choice method in precision species identification. The ITS region is one of the official fungal barcoding DNA markers, although in some cases sequencing of the ITS re-gion may, due to misidentification, mislabeling or nomen-clature errors in public databases, lead to incorrect or insuf-ficient identification, as is currently a case in the genus Tu b e r. The aim of this study was to test, which ITS primer pairs are most appropriate and optimal for Tu b e r species DNA region amplification. Thereby we (1) compared ampli-fication success for different Tu b e r species using fungal spe-cific primer pair ITS1f and ITS4 and (2) compared amplifi-cation success using different ITS primer pair combinations in amplifying DNA region an example species Tuber aesti-vum. Based on results, Tuber aestivum was one of the most reluctant Tu b e r species in this study and in most cases failed to amplify with the above primer pair. After comparing dif-ferent ITS primer pairs, we conclude that the primer pair ITS5 and ITS7 is the most appropriate primer pair for ampli-fication DNA region of T. ae stiv um as it resulted in high am-plification success from ectomycorrhizal root tips. Based on sequences, gained from public databases, we found that ITS1f and ITS6 primers have a mismatch in one base pair compared to the target sequence of Tuber aestivum, thus re-sulting in poor or no amplification success. Although prim-er pair ITS5 and ITS7 in our study was proven to be the most appropriate primer pair in amplifying DNA region Tu b e r aestivum species, further analysis about appropriateness of it for a general barcoding and identification of ectomycorrhiza in complex community samples is needed.
Ključne besede: Tuber spp., ITS region, PCR amplification, ITS primers
Objavljeno v DiRROS: 30.07.2020; Ogledov: 1594; Prenosov: 1176
Celotno besedilo (6,81 MB)
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