Fig. 5From: Genetic diversity and population structure of black cottonwood (Populus deltoides) revealed using simple sequence repeat markersPopulation structure of six provenance populations of P. deltoides. (a) The principal coordinates analysis (PCoA) of six populations of P. deltoides. (b) UPGMA analysis of six populations of P. deltoides based on Nei’s genetic distance. (c) The unrooted tree based on Nei’s genetic distance for six P. deltoides populations. The pie chart reflects the distribution proportion of individuals of the provenance populations in the two groupsBack to article page