Abstract
Turtle egg fusariosis, caused by pathogens of the Fusarium solani species complex (FSSC), threatens turtle populations globally, through embryonic mortality and hatching failure. Host–associated microbiomes, including the bacteriome and mycobiome, are hypothesized to mediate disease outcomes in oviparous vertebrates, but this remains largely unexplored. Here, we characterised the inner–egg bacteriome and mycobiome of uninfected and FSSC–infected eggs at three developmental stages in the vulnerable yellow–spotted Amazon river turtle (Podocnemis unifilis). Lower mycobiome evenness was strongly associated with increased FSSC infection propensity and intensity. Regardless of infection status, higher microbial diversity positively correlated with hatching success, and hatched eggs showed more complex interkingdom interactions. We also identified bacterial and fungal genera whose relative abundance was negatively associated with FSSC infection. These findings support the hypothesis that the egg microbiome may influence infection and hatching outcomes, with implications for microbiome–informed conservation strategies for threatened turtle populations.
Similar content being viewed by others
Egg disinfection improves larval survival and shapes the microbial community in snubnose pompano (Trachinotus blochii)
Bacterial communities of the oviduct of turkeys
Early-life gut microbiota differentiation in sympatric wild raptors
Acknowledgements
The authors are grateful to all the staff of Tiputini Biodiversity Station, especially to everyone involved in the P. unifilis reintroduction project, especially to Juan Carlos Rodriguez, Santiago Shiguango, José Macanilla, Mariano Grefa and Luis Ganchoso. We thank the staff of the Plant Biotechnology lab at USFQ for all the support during field work, Tomi Sugahara for her assistance with the paperwork for the collection permits, Consuelo de Romo for her assistant with field work logistics, and Ulrike Stehle for her help with laboratory work. The authors acknowledge the Kichwa and Waorani Indigenous communities for granting access to their land and their efforts to conserve the Amazon forest and its biodiversity. The Tiputini Biodiversity Station and the Institute of Evolutionary Ecology and Conservation Genomics at Ulm University both supported the fieldwork. This study was carried out under the collection research permit no. MAE–DNB–CM–2016–0046–M–0003 and exportation permit no.158–2019–EXP–CM–FAU–DNB/MA awarded by the Environmental Ministry of Ecuador.
Funding
S.S discloses support for the research and publication of this work from the German Research Foundation (DFG SO 428/19–1). A.S.C discloses support for the initial research underlying this work from the Gender Equality Office at Ulm University. M.G., K.W., M.L.T., and D.R. declare no relevant funding. Open Access funding enabled and organized by Projekt DEAL.
Author information
Authors and Affiliations
Corresponding authors
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary information
Transparent Peer Review file (download PDF )
Supplementary Information (download PDF )
Reporting summary (download PDF )
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Reprints and permissions
About this article
Cite this article
Carranco, A.S., Romo, D., Torres, M.d.L. et al. Egg microbiome of the yellow-spotted Amazon river turtle (Podocnemis unifilis) modulates fusariosis fungal infection and hatching success.
Commun Biol (2026). https://doi.org/10.1038/s42003-026-10404-8
Received:
Accepted:
Published:
DOI: https://doi.org/10.1038/s42003-026-10404-8
Source: Ecology - nature.com
