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Abstract It is increasingly recognized that different genetic variants of hosts can uniquely shape their microbiomes. Invasive species often evolve in their introduced ranges, but little is known about the potential for their microbial associations to change during invasion as a result. We asked whether host genotype (G), microbial environment (E), or their interaction (G × E) affected the composition and diversity of host-associated microbiomes inCentaurea solstitialis(yellow starthistle), a Eurasian plant that is known to have evolved novel genotypes and phenotypes and to have altered microbial interactions, in its severe invasion of CA, USA. We conducted an experiment in which native and invading plant genotypes were inoculated with native and invaded range soil microbial communities. We used amplicon sequencing to characterize rhizosphere bacteria in both the experiment and the field soils from which they were derived. We found that native and invading plant genotypes accumulated different microbial associations at the family level in each soil community, often counter to differences in family abundance between soil communities. Root associations with potentially beneficial Streptomycetaceae were particularly interesting, as these were more abundant in the invaded range field soil and accumulated on invading genotypes. We also found that bacterial diversity is higher in invaded soils, but that invading genotypes accumulated a lower diversity of bacteria and unique microbial composition in experimental inoculations, relative to native genotypes. Thus variation in microbial associations of invaders was driven by the interaction of plant G and microbial E, and rhizosphere microbial communities appear to change in composition in response to host evolution during invasion.
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Leafcutter ants enhance microbial drought resilience in tropical forest soil
Abstract We conducted a research campaign in a neotropical rainforest in Costa Rica throughout the drought phase of an El‐Nino Southern Oscillation event to determine microbial community dynamics and soil C fluxes. Our study included nests of the leafcutter antAtta cephalotes, as soil disturbances made by these ecosystem engineers may influence microbial drought response. Drought decreased the diversity of microbes and the abundance of core microbiome taxa, including Verrucomicrobial bacteria and Sordariomycete fungi. Despite initial responses of decreasing diversity and altered composition, 6 months post‐drought the microbiomes were similar to pre‐drought conditions, demonstrating the resilience of soil microbial communities to drought events.A. cephalotesnests altered fungal composition in the surrounding soil, and reduced both fungal mortality and growth of Acidobacteria post‐drought. Drought increased CH4consumption in soils due to lower soil moisture, andA. cephalotesnests decrease the variability of CH4emissions in some soil types. CH4emissions were tracked by the abundance of methanotrophic bacteria and fungal composition. These results characterize the microbiome of tropical soils across both time and space during drought and provide evidence for the importance of leafcutter ant nests in shaping soil microbiomes and enhancing microbial resilience during climatic perturbations.
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- Award ID(s):
- 2012878
- PAR ID:
- 10514223
- Publisher / Repository:
- Environmental Microbiology
- Date Published:
- Journal Name:
- Environmental Microbiology Reports
- Volume:
- 16
- Issue:
- 3
- ISSN:
- 1758-2229
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1111/1758-2229.13251
