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Abstract PremiseEndophytic plant‐microbe interactions range from mutualistic relationships that confer important ecological and agricultural traits to neutral or quasi‐parasitic relationships. In contrast to root‐associated endophytes, the role of environmental and host‐related factors in the acquisition of leaf endophyte communities at broad spatial and phylogenetic scales remains sparsely studied. We assessed endofoliar diversity to test the hypothesis that membership in these microbial communities is driven primarily by abiotic environment and host phylogeny. MethodsWe used a broad geographic coverage of North America in the genusHeucheraL. (Saxifragaceae), representing 32 species and varieties across 161 populations. Bacterial and fungal communities were characterized using 16S and ITS amplicon sequencing, respectively, and standard diversity metrics were calculated. We assembled environmental predictors for microbial diversity at collection sites, including latitude, elevation, temperature, precipitation, and soil parameters. ResultsAssembly patterns differed between bacterial and fungal endophytes. Host phylogeny was significantly associated with bacteria, while geographic distance was the best predictor of fungal community composition. Species richness and phylogenetic diversity were consistent across sites and species, with only fungi showing a response to aridity and precipitation for some metrics. Unlike what has been observed with root‐associated microbial communities, in this system microbes show no relationship with pH or other soil factors. ConclusionsOverall, this work improves our understanding of the large‐scale patterns of diversity and community composition in leaf endophytes and highlights the relative significance of environmental and host‐related factors in driving different microbial communities within the leaf microbiome.
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Exploring the root-associated microbiome of the resurrection plant Myrothamnus flabellifolia
Abstract Aims and backgroundThe resurrection plantMyrothamnus flabellifoliatolerates complete desiccation and is a great model for studying how plants cope with extreme drought. Root-associated microbes play a major role in stress tolerance and are an attractive target for enhancing drought tolerance in staple crops. However, how these dynamics play out under the most extreme water limitation remains underexplored. This study aimed to identify bacterial and fungal communities that tolerate extreme drought stress in the bulk soil, rhizosphere, and endosphere ofM. flabellifolia. MethodsHigh-throughput amplicon sequencing was used to characterise the microbial communities associated withM. flabellifolia. ResultsThe bacterial phyla that were most abundant across all compartments wereAcidobacteriota, Actinobacteriota, Chloroflexota, Planctomycetota,andPseudomonadota, while the most abundant fungal phyla wereAscomycotaandBasidiomycota. Although the bulk soil hosted multiple beneficial root-associated microbes, the rhizosphere compartment showed the highest functional diversity of bacteria and fungi. In contrast, the endosphere exhibited a low abundance and diversity of microbes. These findings share consistent with the theory thatM. flabellifoliarecruits soil microbes from the bulk to the rhizosphere and finally to the endosphere. It is possible that these microbes could promote drought tolerance in associated plant tissues. ConclusionWe find that compartments act as the major driver of microbial diversity, but the soil physicochemical factors also influence microbial composition. These results suggest that the root-associated microbiome ofM. flabellifoliais highly structured and may aid in plant function.
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- Award ID(s):
- 1906094
- PAR ID:
- 10412796
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Plant and Soil
- Volume:
- 500
- Issue:
- 1-2
- ISSN:
- 0032-079X
- Format(s):
- Medium: X Size: p. 53-68
- Size(s):
- p. 53-68
- Sponsoring Org:
- National Science Foundation
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