Frequency distribution of scopolin and scopoletin relative levels in the AI-RILs and parental lines roots. Plants used for genetic mapping were grown in in vitro liquid cultures under a photoperiod of 16 h light (35 μmol m-2 s-1) at 20°C and 8 h dark at 18°C. Coumarins content in the roots of the AI-RILs population and parental lines (accessions Col-0 and Est-1) were determined by HPLC. (A) Scopolin contents were determined in methanol extracts without hydrolysis. (B) Methanol extracts subjected to enzymatic hydrolysis were used for scopoletin quantification. The data analysis consisted of scopolin and scopoletin relative levels measured as area% of total chromatogram signals. The average values of Col-0 and Est-1 are indicated with arrows.