Figure 2.

Levels of petunia phenylpropanoid glycosylated scent compounds increase in parallel to flower development. Glycosylated scent compounds and aglycones (Free) from corollas of petunia line P720 were extracted at 1800 h and their levels were measured by GC–MS. Developmental stages of corollas: 3.5 cm buds, 4.5 cm buds, anthesis, and 1, 2, and 3 DPA. (A–F) Levels of glycosides and aglycones are presented for (A) the sum of the set of scent compounds with glycosylation-compatible hydroxyl groups, consisting of (B) benzyl alcohol, (C) phenylethyl alcohol, (D) eugenol, (E) isoeugenol, and (F) vanillin. Columns represent the mean values of three to four independent experiments. SEs are indicated by vertical lines. Significance of differences between levels of glycosylated scent compounds and their corresponding aglycones were calculated by Student's t-test, ^*P ≤ 0.05. FW, fresh weight. (G) Dynamic headspace analyses of total emitted volatiles followed by GC–MS were performed for 24 h (starting at 1600 h) on P720 petunia corollas at different developmental stages. Columns represent the mean values of three to five independent experiments. SEs are indicated by vertical lines.