Fig. 4

Comparative analysis of volatile organic compounds (VOCs) from hoary stock, collected at either pre- or post-blooming stages. a Chromatograms of total ion current of VOCs from post-blooming hoary stock. b Chromatograms of total ion current of VOCs from pre-blooming hoary stock. c Identified 21 unique VOCs from post-blooming hoary stock. d Identified 15 same VOCs from pre-and post-blooming hoary stock