# Supplemental Material for Sorgini et al., 2021

**Supplemental Figure 1 NAM RIL Transgressive Segregation. **NAM RIL families CML103 (**A**),
CML333 (**B**), NC358 (**C**), and Tx303 (**D**) were sorted by δ^{13}C and plotted. Parental lines are
shown in red.

**Supplemental Figure 2 Element and δ ^{13}C Full Correlation
Matrix.** A full correlation matrix of element and δ

^{13}C mean values is show. The diagonal displays histograms of each dataset. Pearson’s r is shown in the upper panel. Scatter plots and best fit line are shown in the lower panel.

**Supplemental Figure 3 Element QTL Mapping by Chromosome. **Significant element QTL are shown by maize chromosomes 1 through
10 on the x-axis (in cM). Each NAM RIL family is represented by a symbol;
CML103 (○), CML333 (x), NC358 (□), and Tx303 (Δ). Each element is designated by
color. Significance thresholds (dashed
horizontal line) were determined using 200 permutations, alpha=0.05 for each
QTL independently.

**Supplemental Figure 4 Genome Wide Association Study for δ**Manhattan plot showing significance of SNPs derived from a mixed linear model using the Bayesian information criterion to select the optimal number of principal components. The significance threshold represents the Bonferroni correction of familywise error rate.

^{13}C.