Quantitative genetic analyses
Mean values of at least three replicates were calculated for each isoprenoid compound measured, for each AI-RIL and each natural accession. These values were used in QTL mapping and GWAS. The broad sense heritability (H2) for isoprenoid accumulation for the AI-RIL population was estimated according to the formula: H2 = VG /(VG + VE), where VG is the among-genotype variance component and VE is the residual (error) variance. For GWAS heritability, estimates have been extracted from the mixed model accordingly.