title: Spatial structuring of bacterial communities within individual Ginkgo biloba trees.
abstract: Plant-associated microorganisms affect the health of their hosts in diverse ways, yet the distribution of these organisms within individual plants remains poorly understood. To address this knowledge gap, we assessed the spatial variability in bacterial community diversity and composition found on and in aboveground tissues of individual Ginkgo biloba trees. We sampled bacterial communities from > 100 locations per tree, including leaf, branch and trunk samples and used high-throughput sequencing of the 16S rRNA gene to determine the diversity and composition of these communities. Bacterial community structure differed strongly between bark and leaf samples, with bark samples harbouring much greater bacterial diversity and a community composition distinct from leaves. Within sample types, we observed clear spatial patterns in bacterial diversity and community composition that corresponded to the samples' proximity to the exterior of the tree. The composition of the bacterial communities found on trees is highly variable, but this variability is predictable and dependent on sampling location. Moreover, this work highlights the importance of carefully considering plant spatial structure when characterizing the microbial communities associated with plants and their impacts on plant hosts.
authors.affiliation: Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, 80309, USA.|Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309, USA.
authors.forename: Jonathan W
authors.identifier: http://orcid.org/0000-0003-3309-2709
authors.initials: JW
authors.lastname: Leff
authors.affiliation: Arnold Arboretum of Harvard University, Boston, MA, 02131, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Del Tredici
authors.affiliation: Arnold Arboretum of Harvard University, Boston, MA, 02131, USA.|Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA.
authors.forename: William E
authors.initials: WE
authors.lastname: Friedman
authors.affiliation: Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, 80309, USA.|Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309, USA.
authors.forename: Noah
authors.initials: N
authors.lastname: Fierer
mesh_terms: D001419:Bacteria / Q000235:genetics*; D001483:Base Sequence; D044822:Biodiversity; D020441:Ginkgo biloba / Q000382:microbiology*; D018515:Plant Leaves / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017423:Sequence Analysis, RNA; D014197:Trees / Q000382:microbiology*
chemical_list: D012336:RNA, Ribosomal, 16S