Assessment of Endophytic Fungal Community in Palm Leaves and Their Biocontrol Potential

Abstract

Microbial endophytes live asymptomatically within a host plant and contribute positively to its fitness. Endophytes associate ubiquitously with all plants examined so far and form an integral part of the host for processes such as nutrient uptake and stress response and traits like disease resistance. Well-characterized host–endophyte interaction models exist, but little is known about the microbiome of the monocot plant host, palm. In this study, we identified the endophytic fungal community associated with mule palm leaves with an objective to test their antagonist effects on lethal pathogens of palms. The leaflets of mule palms were sampled across five sites in Central and South Florida, and fungal endophytes were identified using culture-dependent (CD) and amplicon sequence-based culture-independent (CI) methods. Operational taxonomic units (OTUs) corresponding to phylum Ascomycota were identified by both approaches, whereas Basidiomycota were only detected using the CI method. Among the ascomycetes, a small (22%) overlap in the OTUs at the genus level was observed between the two methods, whereas the majority (64%) of OTUs were detected using the CI approach. In vitro cocultivation of endophytes with palm pathogens was observed to produce three distinct interaction phenotypes: inhibition zone, niche establishment, and overlapping growth. Eight endophytes capable of inhibiting fungal pathogen growth in vitro were also identified, suggesting a biocontrol potential for endophyte-derived secondary metabolites. A better understanding of the composition, assembly, and ecology of palm-associated microbial communities would eventually lead to healthy and resilient palms. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .