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12 páginas.- 3 figuras.- 1 tablas.- referencias.- Additional supporting information can be found online in the Supporting Information section at the end of this article.https://doi.org/10.1111/ele.14271, Despite host-fungal symbiotic interactions being ubiquitous in all ecosystems, understanding how symbiosis has shaped the ecology and evolution of fungal spores that are involved in dispersal and colonization of their hosts has been ignored in life-history studies. We assembled a spore morphology database covering over 26,000 species of free-living to symbiotic fungi of plants, insects and humans and found more than eight orders of variation in spore size. Evolutionary transitions in symbiotic status correlated with shifts in spore size, but the strength of this effect varied widely among phyla. Symbiotic status explained more variation than climatic variables in the current distribution of spore sizes of plant-associated fungi at a global scale while the dispersal potential of their spores is more restricted compared to free-living fungi. Our work advances life-history theory by highlighting how the interaction between symbiosis and offspring morphology shapes the reproductive and dispersal strategies among living forms., Alexander von Humboldt-Stiftung, grant/Award Number: Feodor-Lynen Fellowship; Australian Research Council, Grant/Award Number: DP190103714 and FT0100590; BundesmForschunginisterium für Bildung und , Grant/Award Number: 01LC1501A; Deutsche Forschungsgemeinschaft, Grant/Award Number: HE6183; Deutscher Akademischer Austauschdienst; Division of Environmental Biology, Grant/Award Number: 1623040 and 1655759; Grantová Agentura České Republiky, Grant/Award Number: 21-17749S; H2020 European Research Council, Grant/Award Number: 647038 and 694368; Universities Australia

Despite host-fungal symbiotic interactions being ubiquitous in all ecosystems, understanding how symbiosis has shaped the ecology and evolution of fungal spores that are involved in dispersal and colonization of their hosts has been ignored in life-history studies. We assembled a spore morphology database covering over 26,000 species of free-living to symbiotic fungi of plants, insects and humans and found more than eight orders of variation in spore size. Evolutionary transitions in symbiotic status correlated with shifts in spore size, but the strength of this effect varied widely among phyla. Symbiotic status explained more variation than climatic variables in the current distribution of spore sizes of plant-associated fungi at a global scale while the dispersal potential of their spores is more restricted compared to free-living fungi. Our work advances life-history theory by highlighting how the interaction between symbiosis and offspring morphology shapes the reproductive and dispersal strategies among living forms. peerReviewed

Symbioses between plants and fungi are important in both promoting plant fitness and maintaining soil structure. The ways in which these relationships change across an urban gradient is subject to debate. Here we measured root colonisation including the presence of arbuscular mycorrhizal fungi, non-mycorrhizal fungi, and root hair presence. We found no evidence of changes in levels of arbuscular mycorrhizal fungal colonisation across an urban gradient, colonisation levels being driven instead by plant community. However, we did observe an increase in non-mycorrhizal fungal colonisation in association with increasing urbanity. Additionally, we observed an urban-related increase in root hair presence. Using principal component analysis we were able to provide strong evidence for these patterns being driven by an “urban syndrome”, rather than soil chemistry. Our findings have important implications for the wider understanding of abiotic stresses on fungal endophyte presence and shed light on the impacts of urbanity upon plant roots.

The microbial communities inhabiting urban soils determine the functioning of these soils, in regards to their ability to cycle nutrients and support plant communities. In an increasingly urbanized world these properties are of the utmost importance, and the microbial communities responsible are worthy of exploration. We used 53 grassland sites spread across Berlin to describe and explain the impacts of urbanity and other environmental parameters upon the diversity and community composition of four microbial groups. These groups were (i) the Fungi, with a separate dataset for (ii) the Glomeromycota, (iii) the Bacteria, and (iv) the protist phylum Cercozoa. We found that urbanity had distinct impacts on fungal richness, which tended to increase. Geographic distance between sites and soil chemistry, in addition to urbanity, drove microbial community composition, with site connectivity being important for Glomeromycotan communities, potentially due to plant host communities. Our findings suggest that many microbial species are well adapted to urban soils, as supported by an increase in diversity being a far more common result of urbanity than the reverse. However, we also found distinctly separate distributions of operational taxonomic unit (OTU)s from the same species, shedding doubt of the reliability of indicator species, and the use of taxonomy to draw conclusion on functionality. Our observational study employed an extensive set of sites across an urbanity gradient, in the region of the German capital, to produce a rich microbial dataset; as such it can serve as a blueprint for other such investigations.

In this study the impacts of urbanity on physical soil properties were explored by measuring water stable aggregates, combined particle size, infiltration rate and hydrophobicity across an urban gradient. The use of a gradient allowed for the relative importance of different environmental drivers to be assessed. We sampled 54 sites across Berlin and used a pre-existing database of environmental variables to extract three main axes of variation relating to urbanity, soil nutrient content, and heavy metal content. These axes, along with site age, were used to explore the drivers of changes in physical properties across an urban landscape. The percentage of water stable aggregates was found to decrease with urbanity, whilst infiltration rate was found to increase. Hydrophobicity did not appear to be influenced by urbanity but interacted with both infiltration rate and water stable aggregates. Combined particle sizes in the soil were found to increase with urbanity. Our findings provide evidence for urbanity being an important driver of variation in physico-chemical soil properties, which has implications for the provision of ecosystem services by these soils.