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.

Endophytic Microbiota Associated with the Root Tips and Leaves of Baccharis dracunculifolia

“…A few other taxa were recorded at much lower abundances (≤0.8%): Chlorobi (galled plant roots, galled leaves, and healthy leaves), Calditrix (healthy leaves), AD3 (galled plant roots), Armatimonadetes (galled plant roots), Chlamydia (galled plant roots), Cyanobacteria (galled plant roots and healthy leaves), Elusimicrobia (galled plant roots), Fusobacteria (galled plant roots), Gemmatimonadetes (galled leaves, and healthy leaves), OC31 (healthy leaves), OD1 (galled plant roots), Planctomycetes (galled plant roots), Spirochaetes (galled plant roots), Synergistetes (galled plant roots), Tenericutes (galled plant roots), TM6 (galled plant roots), TM7 (galled plant roots), and WPS-2 (galled plant roots). These findings are consistent with other cultivation-independent studies that revealed that a few bacterial phyla predominate in the phyllosphere and roots [ 38,39 ] …”

Forest tree genomics: 10 achievements from the past 10 years and future prospects

“…For instance, Cordier et al (2012a) showed within-canopy variations in foliar fungal communities of beech. Leff et al (2015) obtained similar results in the case of bacterial communities associated to leaf and bark of Gingko biloba trees. By opening the microbial world to ecologists, the next-gen revolution also gave rise to larger scale studies, aimed at assessing the influence of climate and other global change components on tree-associated microbial communities.…”

Metabarcoding of Bacteria Associated with the Acute Oak Decline Syndrome in England

“…Similar to studies of other plant organs, Proteobacteria dominated the communities associated with oak tissue and included the presence of Bacteroidetes and Firmicutes [6,13,15,19,[78][79][80][81]. Interestingly, Juncker et al [6] identified a member of the Gammaproteobacteria (Enterobacteriaceae) as dominant in stamina and styles whereas a member of the Pseudomonadaceae was identified as dominant in the oak microbiome.…”

“…Both sites had considerably lower OTU numbers and the phylogenetic diversity was lower than in the other three sites ( Table 2). The number of taxa detected at all sites was generally comparable to the phyllosphere microbiome consisting of several hundred or less taxa [6,[13][14][15][16].…”