Figure 1.
Map of sample locations along Caney Fork River in Tennessee and Yadkin River in North Carolina along with phylogenetic tree for the 23 individuals of P. deltoides generated from 20 simple sequences repeat markers.
Each symbol on the maps represents the location of each tree sampled along the river and the corresponding symbol in the phylogenetic tree represents the genotypic relationships amongst individual hosts. The size of the symbol on the branch corresponds to the number of trees in each of the three putative host clonal groups.
Figure 2.
Taxonomic distribution of bacterial (A) and fungal (B) communities from roots of Populus deltoides.
The first row of stacked bar represents the overall relative abundance across the entire data set, the second row represents endosphere vs. rhizosphere, third row represents the relative abundance in each watershed and the fourth row represents the relative abundance in May vs. September.
Figure 3.
A phylogram-based illustration of the experimental design and difference in phylogenetic-based community structure between rhizosphere, endosphere, watersheds and seasons for bacterial (A) and fungal (B) communities.
Rhizosphere is represented by brown edges and endosphere by green edges. Similarly, two the watersheds are represented by orange and blue edges for Tennessee and North Carolina, respectively. The end nodes represent the two seasons of sample collection. The number at the node represents the p-values (red for insignificant, blue for significant p≤0.05) generated by comparing the unweighted UniFrac distance metrics between two conditions (left and right nodes) using the adonis function of vegan package in R. Phylograms represent (A) bacterial and (B) fungal communities.
Figure 4.
Variance partitioning of bacterial and fungal communities from the roots of Populus deltoides into soil properties, host properties, spatial, host genotype, seasonal and beta diversity of corresponding bacterial or fungal community.
Each bar represents total variance partitioned into pure effect or interaction of two or all factors. Only variance proportions that were statistically significant (p≤0.05) are listed. Variables for host and soil properties were selected based on stepwise selection (forward and backward) to remove non-significant terms from the model. (A) Variance partitioning of bacterial community from endosphere and rhizosphere. (B) Variance partitioning of fungal community from endosphere and rhizosphere.
Table 1.
Distribution of rhizosphere specific, shared, and endosphere specific bacterial and fungal OTUs among all the sampled trees.