Additional file 2: Figure S1. of Genetic diversity and association mapping of mineral element concentrations in spinach leaves

The ring phylogenetic tree combining structure populations (Q1 to Q4) from STRUCTURE 2 and the Maximum Likelihood (ML) method from MEGA 6. The spinach accession number, the accession original country, and the structure population (cluster) were merged together into one taxon name as each spinach accession ID in the combined tree drawn by MEGA 6. The colored shape and branch of each cluster matched the structure population (red round shape for Q1, green triangle for Q2, blue triangle for Q3, yellow diamond for Q4, and the black square with the black branch for the admixture in 292 USDA GRIN spinach germplasm accessions. (XLSX 149 kb)