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Title: Invasibility of a North American soil ecosystem to amphibian-killing fungal pathogens
North American salamanders are threatened by intercontinental spread of chytridiomycosis, a deadly disease caused by the fungal pathogenBatrachochytrium salamandrivorans(Bsal). To predict potential dispersal ofBsalspores to salamander habitats, we evaluated the capacity of soil microbial communities to resist invasion. We determined the degree of habitat invasibility using soils from five locations throughout the Great Smoky Mountains National Park, a region with a high abundance of susceptible hosts. Our experimental design consisted of replicate soil microcosms exposed to different propagule pressures of the non-native pathogen,Bsal, and an introduced but endemic pathogen,B. dendrobatidis(Bd). To compare growth and competitive interactions, we used quantitative PCR, live/dead cell viability assays, and full-length 16S rRNA sequencing. We found that soil microcosms with intact bacterial communities inhibited bothBsalandBdgrowth, but inhibitory capacity diminished with increased propagule pressure.Bsalshowed greater persistence thanBd. Linear discriminant analysis (LDA) identified the family Burkolderiaceae as increasing in relative abundance with the decline of both pathogens. Although our findings provide evidence of environmental filtering in soils, such barriers weakened in response to pathogen type and propagule pressure, showing that habitats vary their invasibility based on properties of their local microbial communities.  more » « less
Award ID(s):
2011278
PAR ID:
10559524
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Proceedings of the Royal Society B
Date Published:
Journal Name:
Proceedings of the Royal Society B: Biological Sciences
Volume:
291
Issue:
2021
ISSN:
0962-8452
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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