title: A comparison of the community diversity of foliar fungal endophytes between seedling and adult loblolly pines (Pinus taeda).
abstract: Fungal endophytes represent one of the most ubiquitous plant symbionts on Earth and are phylogenetically diverse. The structure and diversity of endophyte communities have been shown to depend on host taxa and climate, but there have been relatively few studies exploring endophyte communities throughout host maturity. We compared foliar fungal endophyte communities between seedlings and adult trees of loblolly pines (Pinus taeda) at the same seasons and locations by culturing and culture-independent methods. We sequenced the internal transcribed spacer region and adjacent partial large subunit nuclear ribosomal RNA gene (ITS-LSU amplicon) to delimit operational taxonomic units and phylogenetically characterize the communities. Despite the lower infection frequency in seedlings compared to adult trees, seedling needles were receptive to a more diverse community of fungal endophytes. Culture-free method confirmed the presence of commonly cultured OTUs from adult needles but revealed several new OTUs from seedling needles that were not found with culturing methods. The two most commonly cultured OTUs in adults were rarely cultured from seedlings, suggesting that host age is correlated with a selective enrichment for specific endophytes. This shift in endophyte species dominance may be indicative of a functional change between these fungi and their loblolly pine hosts.
authors.affiliation: Department of Biology, Duke University, Durham, NC 27708, USA. Electronic address: ryoko.oono@lifesci.ucsb.edu.
authors.forename: Ryoko
authors.initials: R
authors.lastname: Oono
authors.affiliation: Department of Biology, Duke University, Durham, NC 27708, USA.
authors.forename: Emilie
authors.initials: E
authors.lastname: Lefèvre
authors.affiliation: Department of Biology, Duke University, Durham, NC 27708, USA.
authors.forename: Anita
authors.initials: A
authors.lastname: Simha
authors.affiliation: Department of Biology, Duke University, Durham, NC 27708, USA.
authors.forename: François
authors.initials: F
authors.lastname: Lutzoni
mesh_terms: D058448:Biota; D016000:Cluster Analysis; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D060026:Endophytes / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D005658:Fungi / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D020508:Fungi, Unclassified; D008969:Molecular Sequence Data; D010802:Phylogeny; D041603:Pinus taeda / Q000382:microbiology*; D018515:Plant Leaves / Q000382:microbiology; D012335:RNA, Ribosomal / Q000235:genetics; D036226:Seedlings / Q000382:microbiology; D017422:Sequence Analysis, DNA
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012335:RNA, Ribosomal; C065096:RNA, ribosomal, 26S
keywords: Class 3 endophytes; Fungal communities; Phylogeny; Plant-fungal symbiosis