Mycological Insights Into Wetland Fungal Communities: The Mycobiome of Camassia in the Pacific Northwest

Abstract

Fungal communities in ephemeral wetland habitats of the Pacific Northwest (PNW) are poorly understood. Because Camassia (camas) populations are a distinctive component of native plant communities in wetland areas of the PNW, camas plant tissue, seed, and associated soil samples were taken from populations growing in wetland habitats in Oregon, Idaho, and Washington. Enumeration of fungal taxa from above- and below-ground camas tissues was accomplished using high-throughput sequencing of fungal internal transcribed spacer genes. Operational taxonomic units (OTUs) affiliated with at least 200 fungal families were found in root, tunic, leaf, rhizosphere, and proximal soil samples (n = 2,984 OTUs). Significant variation in fungal community composition was explained by sample type, habitat of origin, and their interaction. Taxa related to Cladophialophora, Cadophora, and Exophiala, believed to be dark septate endophytes, together with Penicillium, Ceratobasidium, and Ilyonectria were differentially abundant in roots compared with the rhizospheres. Seed-associated communities comprised just 127 OTUs but were highly diverse with at least 50 families detected. Comparison of communities from camas seeds, leaves, roots, and rhizospheres revealed 68 fungal taxa in common, including Alternaria, Fusarium, Selenophoma, Cladosporium, Cryptococcus, and Sporobolomyces. This study provides a baseline understanding into the composition and diversity of fungal communities associated with camas growing in wetland habitats in the PNW.