Figure 1. Ectopic expression of TPS10 and the point mutant TPS10M results in greater headspace abundance of (E)-β-farnesene and/or (E)-α-bergamotene versus WT.

(A) Simplified mechanism of TPS10 and TPS10M (modified from Köllner et al., 2009). TPS10 (B, C) and TPS10M lines (D, E) consistently emit more (E)-β-farnesene (left panels) and/or (E)-α-bergamotene (right panels) than WT plants from leaves treated with several herbivory-related elicitors (mean ± SEM, n = 4). Note different scales: data in (B, C) and (D, E) are from two separate experiments conducted within the same week; all plants were in the same growth stage (elongated). The headspace of the second fully expanded leaf (+2) on plants was collected without treatment (Con) or for 24-32 h after treatment with wounding and water (W+W; W+OS control), wounding and Manduca sexta oral secretions (W+OS), lanolin (Lan; Lan+MJ control), or lanolin containing 150 μg methyl jasmonate (Lan+MJ). In the constitutive and lanolin treatments, there was very low but detectable (E)-α-bergamotene emission from WT (<0.1 ng); nd, not detected. *P < 0.05, ** P < 0.01 versus WT within each treatment after Holm-Bonferroni corrections for multiple testing if required (WT tested against lines 10-3 and 10-4) following Wilcoxon rank-sum tests or Welch’s t-tests; marginally significant corrected P-values (<0.1) are written above bars; ns, not significant. Non-target volatiles from these plants did not differ among transgenic lines and WT (PCAs in Supplemental Figs. S2 and S3).