Geology and climate influence rhizobiome composition of the phenotypically diverse tropical tree Tabebuia heterophylla

along sites, also display a separation along PCoA Axis 1(Fig 3B); karstic sites (S5 and S6) were located at the negative side of the axis, while serpentine sites (S3 and S4) were at the most posi- tive side of Axis 2 (Fig 3B). This arrangement along Axis 2 suggests a possible effect of the par- ent material, although serpentine and volcanic bacterial communities did not separate completely. We do not discard a potential influence of the annual mean temperature as well. Soil and rhizosphere samples from low altitude karst, which showed a separation from all other sam- ples, have a unique leaf phenotype, composed of three leaflets, abovate and rounded, while all other trees had 5 leaflets (Fig 1, S3A Fig, S3B Fig). The leaves of the low elevation karst are the only ones with a rounded apex with no drip tip, while all others were acute with a drip tip for Fig 2. Alpha diversity plots depicting richness estimations. Panel A shows rarefaction curves of rhizosphere and soil microbial communities for each of three parent materials. Panels are organized from sites with highest to the lowest number of OTUs (serpentine to volcanic) and columns show sites with high and low elevation. Curves were constructed using Chao1 index for samples with up to 30,170 reads. Bars reflect the 95% confidence intervals. Panel B depict rarefaction curves organized by elevation, whereas in panel C samples are color coded by geology while x-axis corresponds to humid and dry climate for each of the three geologies. https://doi.org/10.1371/journal.pone.0231083.g002 PLOS ONE

Rhizobiota of the tropical tree Tabebuia heterophylla PLOS ONE | https://doi.org/10.1371/journal.pone.0231083 April 7, 2020 7 / 16