Correlation analysis of deuterium label incorporation from [5,5-2H2]-mevalonic acid lactone and [5,5-2H2]-1-deoxy-D-xylulose into grape berry sesquiterpenes of the varieties Lemberger (harvested in 2010 (A) or 2012 (B)), Gewürztraminer (C) and Syrah (D). Mean ± SD (n=3-4) is shown for the following sesquiterpenes: α-ylangene (2), an unknown volatile (a), guaia-6,9-diene (3), selina-4,6-diene (4), germacrene D (5) as major sesquiterpene, epi-zonarene (6), γ-cadinene (7), an unknown volatile (b) and β-calacorene (8)) of the varieties Lemberger and Syrah; (E)- β-farnesene (9), (E,Z)-α-farnesene (10) and (E,E)- α-farnesene (11) as the major sesquiterpene), cubebol (12), an unknown volatile (c) and copaene (14) of the Gewürztraminer variety (labeling of sesquiterpenes according to Fig. 1).