Stressed out symbiotes:hypotheses for the influence of abiotic stress on arbuscular mycorrhizal fungi

Abiotic stress is a widespread threat to both plant and soil communities. Arbuscular mycorrhizal (AM) fungi can alleviate effects of abiotic stress by improving host plant stress tolerance, but the direct effects of abiotic stress on AM fungi are less well understood. We propose two hypotheses predicting how AM fungi will respond to abiotic stress. The stress exclusion hypothesis predicts that AM fungal abundance and diversity will decrease with persistent abiotic stress. The mycorrhizal stress adaptation hypothesis predicts that AM fungi will evolve in response to abiotic stress to maintain their fitness. We conclude that abiotic stress can have effects on AM fungi independent of the effects on the host plant. AM fungal communities will change in composition in response to abiotic stress, which may mean the loss of important individual species. This could alter feedbacks to the plant community and beyond. AM fungi will adapt to abiotic stress independent of their host plant. The adaptation of AM fungi to abiotic stress should allow the maintenance of the plant-AM fungal mutualism in the face of changing climates. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00442-016-3673-7) contains supplementary material, which is available to authorized users

Sequences Lopez-Garcia 454

This file contains the sequences from the experiment with indication of the sample from they were obtained, the OTU classification and sample associated data (plant species, life form and sampling date)

Data from: Plant traits determine the phylogenetic structure of arbuscular mycorrhizal fungal communities

Functional diversity in ecosystems has traditionally been studied using aboveground plant traits. Despite the known effect of plant traits on the microbial community composition, their effects on the microbial functional diversity are only starting to be assessed. In this study, the phylogenetic structure of arbuscular mycorrhizal (AM) fungal communities associated to plant species differing in life cycle and growth form, i.e. plant life forms, was determined to unravel the effect of plant traits on the functional diversity of this fungal group. The results of the 454-pyrosenquencing showed that the AM fungal community composition differed across plant life forms and this effect was dependent on the soil collection date. Plants with ruderal characteristics tended to associate with phylogenetically clustered AM fungal communities. By contrast, plants with resource-conservative traits associated with phylogenetically over-dispersed AM fungal communities. Additionally, the soil collected in different seasons yielded AM fungal communities with different phylogenetic dispersion. In summary, we found that the phylogenetic structure, and hence the functional diversity, of AM fungal communities is dependent on plant traits. This finding adds value to the use of plant traits for the evaluation of belowground ecosystem diversity, functions and processes

Plant traits determine the phylogenetic structure of arbuscular mycorrhizal fungal communities

Functional diversity in ecosystems has traditionally been studied using aboveground plant traits. Despite the known effect of plant traits on the microbial community composition, their effects on the microbial functional diversity are only starting to be assessed. In this study, the phylogenetic structure of arbuscular mycorrhizal (AM) fungal communities associated with plant species differing in life cycle and growth form, that is, plant life forms, was determined to unravel the effect of plant traits on the functional diversity of this fungal group. The results of the 454 pyrosequencing showed that the AM fungal community composition differed across plant life forms and this effect was dependent on the soil collection date. Plants with ruderal characteristics tended to associate with phylogenetically clustered AM fungal communities. By contrast, plants with resource-conservative traits associated with phylogenetically overdispersed AM fungal communities. Additionally, the soil collected in different seasons yielded AM fungal communities with different phylogenetic dispersion. In summary, we found that the phylogenetic structure, and hence the functional diversity, of AM fungal communities is dependent on plant traits. This finding adds value to the use of plant traits for the evaluation of belowground ecosystem diversity, functions and processes.We thank Dr. Rasmus Kjøller and two anonymous reviewers for valuable comments on the manuscript, and Dr. Francisco Bruno Navarro, Domingo Álvarez and Estefanía Berrio for assistance during experiment set‐up and analysis. Funding was provided by Spanish Plan Nacional de I + D + I (project CGL‐2009‐08825) and the Junta de Andalucía, Consejería de Economía, Innovación y Ciencia (project CVI‐7640). SVC and ALG were supported by the Formación de Personal Investigador Programme (Ministerio de Ciencia e Innovación, Spain). During manuscript preparation, ALG was supported by the European Commission under the European Union's Horizon 2020 research and innovation programme (Marie Curie Individual Fellowship grant agreement no. 708530). MO and MV were supported by Estonian Research Council (grant IUT20‐28) and European Regional Development Fund (Centre of Excellence EcolChange). We also thank Consejería de Medio Ambiente, Junta de Andalucía, for permission to work in the Sierra de Baza Natural Park as well as the Real Jardín Botánico (CSIC) and the Banco de Germoplasma Vegetal Andaluz (Junta de Andalucía) for providing us with the seeds used in this study.Peer Reviewe

Site by OTU matrix

This file contains the relative abundance matrix of OTU detected in the study by each sample. Metadata is included