Host-generalist fungal pathogens of seedlings may maintain forest diversity via host-specific impacts and differential susceptibility among tree species

© 2021 The Authors New Phytologist © 2021 New Phytologist Foundation.

Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 231(2021), 1 vom: 15. Juli, Seite 460-474
1. Verfasser: Spear, Erin R (VerfasserIn)
Weitere Verfasser: Broders, Kirk D
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2021
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Clonostachys Mycoleptodiscus Nectriaceae host generalists host-specific impacts multi-host pathogens seedlings tropical forests
Beschreibung
Zusammenfassung:© 2021 The Authors New Phytologist © 2021 New Phytologist Foundation.
Host-specialized pathogens are credited with the maintenance of tropical forest diversity under the Janzen-Connell hypothesis. Yet, in diverse forests, selection may favor pathogens with broad host ranges, given their passive dispersal and the relative rarity of tree species. We surveyed the host associations of potential pathogens isolated from symptomatic seedlings in forests in Panama and used inoculations to assess the pathogenicity and host ranges of 27 fungal isolates, and differences among tree species in susceptibility. Thirty-one of the 33 nonsingleton operational taxonomic units (OTUs) isolated from seedlings are multi-host. All 31 multi-host OTUs exhibit low to moderate specialization, and we observed phylogenetically overdispersed host use for 19 OTUs. The pathogenicity of 10 isolates was experimentally confirmed; nine caused disease in seedlings in multiple families. However, the outcome of infection differs among tree species susceptible to a given multi-host pathogen. Furthermore, some tree species were seemingly resistant to all fungi tested, while others were susceptible to multiple fungi. Tree species adapted to environments with lower disease pressure were most likely to exhibit disease. Our results suggest that generalist pathogens contribute to the maintenance of local and regional forest diversity via host-specific impacts and the exclusion of disease-sensitive trees from disease-prone habitats
Beschreibung:Date Completed 10.06.2021
Date Revised 10.06.2021
published: Print-Electronic
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/nph.17379