(A) Normalized residual median optical densities (y-axis) of 253 RIAILs (x-axis) in response to zinc supplementation are shown. The parental strains are colored: N2, orange; CB4856, blue. (B) Linkage mapping results for optical density (median.EXT) is shown. Genomic position (x-axis) is plotted against the logarithm of the odds (LOD) score (y-axis) for 13,003 genomic markers. Each significant QTL is indicated by a red triangle at the peak marker, and a blue rectangle shows the 95% confidence interval around the peak marker. The percentage of the total variance in the RIAIL population that can be explained by each QTL is shown above the QTL. (C) For each QTL, the normalized residual median optical densities (y-axis) of RIAILs split by genotype at the marker with the maximum LOD score (x-axis) are plotted as Tukey box plots. Each point corresponds to a unique recombinant strain. Strains with the N2 allele are colored orange, and strains with the CB4856 allele are colored blue.