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The mycobiome (fungal microbiome) influences plants—from seed germination to full maturation. While many studies on fungal‐plant interaction studies have focused on known mutualistic and pathogenic fungi, the functional role of ubiquitous endophytic fungi remains little explored. We examined how root‐inhabiting fungi (endophytes) influence range‐expanding plant species. We isolated endophytes from three European intra‐continental range‐expanders and three congenerics that are native both in the range expander's original (southern Europe) and new (northern Europe) range. To standardize our collection, endophytes were obtained from all six plant species growing under controlled conditions in northern (new range of the range expander) and southern (native range of the range expander) soils. We cultivated, molecularly identified and tested the effects of all isolates on seed germination, and growth of seedlings and older plants. Most of the 34 isolates could not be functionally characterized based on their taxonomic identity and literature information on functions. Endophytes affected plant growth in a plant species–endophyte‐specific manner, but overall differed between range‐expanders and natives. While endophytes reduced germination and growth of range‐expanders compared to natives, they reduced seedling growth of natives more than of range‐expanders. Synthesis. We conclude that endophytic fungi have a direct effect on plant growth in a plant growth stage‐dependent manner. While these effects differed between range expanders and natives, the effect strength and significance varied among the plant genera included in the present study. Nevertheless, endophytes likely influence the establishment of newly arriving plants and influence vegetation dynamics.

Plant species that expand their range in response to current climate change will encounter soil communities that may hinder, allow or even facilitate plant performance. It has been shown repeatedly for plant species originating from other continents that these plants are less hampered by soil communities from the new than from the original range. However, information about the interactions between intra‐continental range expanders and soil communities is sparse, especially at community level.Here we used a plant–soil feedback experiment approach to examine if the interactions between range expanders and soil communities change during range expansion. We grew communities of range‐expanding and native plant species with soil communities originating from the original and new range of range expanders. In these conditioned soils, we determined the composition of fungi and bacteria by high‐throughput amplicon sequencing of the ITS region and the 16S rRNA gene respectively. Nematode community composition was determined by microscopy‐based morphological identification. Then we tested how these soil communities influence the growth of subsequent communities of range expanders and natives.We found that after the conditioning phase soil bacterial, fungal and nematode communities differed by origin and by conditioning plant communities. Despite differences in bacterial, fungal and nematode communities between original and new range, soil origin did not influence the biomass production of plant communities. Both native and range expanding plant communities produced most above‐ground biomass in soils that were conditioned by plant communities distantly related to them. Synthesis. Communities of range‐expanding plant species shape specific soil communities in both original and new range soil. Plant–soil interactions of range expanders in communities can be similar to the ones of their closely related native plant species., Communities of range‐expanding plant species shape specific soil communities in both original and new range soil. Plant–soil interactions of range expanders in communities can be similar to the ones of their closely related native plant species.

Šī maģistra darba mērķis bija izpētīt savstarpējas saistības starp priekšstatu par tēvu, stresa pārvarēšanas stratēģijam un depresijas simptomiem pusaudžiem; izpētīt, kādā mērā priekšstats par tēvu un stresa pārvarēšanas stratēģijas prognozē pusaudžu depresijas simptomus. Pētījumā piedalījās 200 pusaudži vecumā no 14 līdz 18 gadiem (M=16,0; SD = 1,21), no kuriem bija 56 zēni un 144 meitenes. Pētījuma dalībnieki aizpildīja Bērnu depresijas aptauju (Children Depression Inventory - CDI, Kovacs, 1979), Bērnu stresa pārvarēšanas (kopinga) stratēģiju aptauju (Children’s Coping Strategies Checklist -CCSC, Ayers & Sandler, 1999), Īpašību kategoriju sistēmu (izveidota maģistra darba ietvaros, balstoties uz CCRT-LU (Luborsky, 1977; Albani, Pokorny, Blaser, Grüninger (2001); Deighton, Jacobs, Fischer, Krampen, Parker, Grenyer (2006 – 2008). English translation: The Core Conflictual Relationship Theme). Pētījuma ietvaros priekšstats par tēvu tiek izskatīts kā negatīvs priekšstats par tēvu un pozitīvs priekšstats par tēvu. Pētījuma rezultāti parāda, ka pozitīvs priekšstats par tēvu ir statistiski nozīmīgi saistīts ar efekīvām stresa pārvarēšanas stratēģijām un zemākiem depresijas simptomiem pusaudžiem, savukart negatīvs priekšstats par tēvu ir statistiski nozīmīgi saistīts ar neefektīvām stresa pārvarēšanas stratēģijām un augstakiem depresijas simptomiem pusaudžiem. Pētījumā iegūtie augšupejošās soļu regresijas rezultāti rāda, ka negatīvs priekšstats par tēvu un izvairīšanās stresa pārvarēšanas stratēģija pozitīvi prognozē un pozitīvā pārstrukturēšana stresa pārvarēšanas stratēģija negatīvi prognozē depresijas simptomus pusaudžu vecumā., The aim of master’s thesis was to study the connection between the representation of the father, coping strategies and depressive symptoms in adolescents; to investigate the extent to which the terpresentation of the father and coping strategies predict depressive symptoms in adolescents. The study involved 200 adolescents aged 14-18 years (mean age 16), of whom 56 were boys and 144 girls. Participants completed Children Depression Inventory -CDI (Kovacs, 1979), Children’s Coping Strategies Checklist -CCSC (Ayers & Sandler, 1999), Feature category system (established within the framework of the master 's thesis, based on CCRT-LU (Luborsky, 1977; Albani, Pokorny, Blaser, Grüninger (2001); Deighton, Jacobs, Fischer, Krampen, Parker, Grenyer (2006 – 2008). English translation: The Core Conflictual Relationship Theme). Within the framework of the research, the image of the father is considered as a negative image of the father and the positive image of the father. The results of the study showed that the positiv representation of the father is statistically significantly related to effective coping strategies and lower depressive symptoms in adolescents, while the negative representation of the father is statistically significantly related to ineffective coping strategies and higher depressive symptoms in adolescents. The results of the stepwise regression of the study showed that the negative representation of the father and avoidance coping strategy positively predicts and the positive reforming coping strategy negatively predicts depressive symptoms in adolescence.

Current climate change has led to latitudinal and altitudinal range expansions of numerous species. During such range expansions, plant species are expected to experience changes in interactions with other organisms, especially with belowground biota that have a limited dispersal capacity. Nematodes form a key component of the belowground food web as they include bacterivores, fungivores, omnivores and root herbivores. However, their community composition under climate change-driven intracontinental range-expanding plants has been studied almost exclusively under controlled conditions, whereas little is known about actual patterns in the field. Here, we use novel molecular sequencing techniques combined with morphological quantification in order to examine nematode communities in the rhizospheres of four range-expanding and four congeneric native species along a 2000 km latitudinal transect from South-Eastern to North-Western Europe. We tested the hypotheses that latitudinal shifts in nematode community composition are stronger in range-expanding plant species than in congeneric natives and that in their new range, range-expanding plant species accumulate fewest root-feeding nematodes. Our results show latitudinal variation in nematode community composition of both range expanders and native plant species, while OTU richness remained the same across ranges. Therefore, range-expanding plant species face different nematode communities at higher latitudes, but this is also the case for widespread native plant species. Only one of the four range-expanding plant species showed a stronger shift in nematode community composition than its congeneric native, and accumulated fewer root-feeding nematodes in its new range. We conclude that variation in nematode community composition with increasing latitude occurs for both range-expanding and native plant species and that some range-expanding plant species may become released from root-feeding nematodes in the new range. This article is protected by copyright. All rights reserved.

Below-ground nematodes are important for soil functioning, as they are ubiquitous and operate at various trophic levels in the soil food web. However, morphological nematode community analysis is time consuming and requires ample training. qPCR-based nematode identification techniques are well available, but high-throughput sequencing (HTS) might be more suitable for non-targeted nematode community analyses. We compared effectiveness of qPCR- and HTS-based approaches with morphological nematode identification while examining how climate warming-induced plant range expansion may influence below-ground nematode assemblages. We extracted nematodes from soil of Centaurea stoebe and C. jacea populations in Slovenia, where both plant species are native, and Germany, where C. stoebe is a range expander and C. jacea is native. Half of each nematode sample was identified morphologically and the other half was analysed using targeted qPCR and a novel HTS approach. HTS produced the highest taxonomic resolution of the nematode community. Nematode taxa abundances correlated between the methods. Therefore, especially relative HTS and relative morphological data revealed nearly identical ecological patterns. All methods showed lower numbers of plant-feeding nematodes in rhizosphere soils of C. stoebe compared to C. jacea. However, a profound difference was observed between absolute and relative abundance data; both sampling origin and plant species affected relative abundances of bacterivorous nematodes, whereas there was no effect on absolute abundances. Taken together, as HTS correlates with relative analyses of soil nematode communities, while providing highest taxonomic resolution and sample throughput, we propose a combination of HTS with microscopic counting to supplement important quantitative data on soil nematode communities. This provides the most cost-effective, in-depth methodology to study soil nematode community responses to changes in the environment. This methodology will also be applicable to nematode analyses in aquatic systems.