Figure 1:

3-D NMS ordination of PPN soil samples from 282 Pecan trees in the Piedmont and Coastal Plain ecoregions of Georgia, USA (Final stress of the 3-D NMS solution = 13.36, proportion of variance explained by all three axes combined = 0.911). Dark gray pyramids (▲) represent pecan soil samples collected from the Piedmont ecoregion (n = 60) and light gray pyramids (▲) represent soil samples collected from the Coastal Plant ecoregion (n = 222).Blue asterisk with names in bold text represent the centroids of the 11 PPN genera (sheath, lesion, cyst, dagger, lance, ring, RKN (root-knot), spiral, stunt, stubby root, pin (Praty)) in the 3-D NMS solution. Piedmont ecoregion soil samples were distributed from the left side of the NMS ordination space to the middle (front to back). Coastal Plain ecoregion soil samples were distributed primarily from the middle to the right side of ordination space. This spatial division of soil samples taken from the Piedmont and Coastal Plains ecoregions strongly suggests that the pecan PPN communities differ between ecoregions.