Volatile organic compounds (VOCs) emitted by Ilex paraguariensis plants are affected by the herbivory of the lepidopteran Thelosia camina and the coleopteran Hedypathes betulinus

Abstract

The profile of volatiles emitted by Ilex paraguariensis, leaves of which are used to produce a popular South American tea, were identified and compared among treatments. Headspace collections were performed for 24-72 hours for control, mechanical damage (MD), herbivory by larvae of Thelosia camina (TC), and by adults of Hedypathes betulinus (HB). Based on gas chromatography-mass spectrometry (GC-MS) and gas chromatography-Fourier transform infrared (GC-FTIR) analyses, 20 compounds were identified, totaling about 7, 5, 20, and 25 μg/plant/treatment (control, MD, TC and HB, respectively). Statistical analyses revealed that control and MD treatments are different from TC and HB herbivory treatments. Furthermore, HB herbivory was distinctive from the other treatments at 24 h in that HB feeding induced a distinctive pattern of emission of terpenes. Major compounds per treatments were decanal for control and DM, 4,8-dimethylnona-1,3,7-triene (DMNT) and 2-undecanone for TC, and DMNT and (E)-β-ocimene for HB.