Chemical diversity of floral scents in 9 species of Philodendron (Araceae) from French Guiana

ABSTRACT

We provide a characterization of the floral scent chemistry of nine species of Philodendron present in French Guiana. The scent samples were obtained by dynamic headspace, in situ in French Guiana, or from plants in the living aroid collection at the Botanical Garden of the University of Brasilia. Overall, we identified 43 volatile organic compounds (VOCs) belonging to the compound classes of monoterpenes, sesquiterpenes, irregular terpenes, benzenoids, aliphatics, jasmone derivatives, and nitrogen-containing compounds. Five of these floral VOCs are new reports for Philodendron. Interestingly, the floral blends in the investigated species were comprised of 3–22 VOCs; but when considering only major VOCs (≥5%), each fragrant blend could be summarized into one up to four constituents. Except for P. acutatum and P. billietiae, whose floral scents were largely dominated (≥93%) by 4-vinylanisole, fragrances of the investigated species were dominated (≥62%) each by a different VOC (i.e. dehydrojasmone, dihydro-β-ionone, (E)-4,8-dimethylnona-1,3,7-trien-5-yl acetate, methyl benzoate, 1,3,5-trimethoxybenzene, dihydrobovolide, or (Z)-jasmone). Consequently, all floral scent compositions significantly differed from one other. We compare our results to published data to provide an insight into the floral scent chemistry within the genus Philodendron. We further discuss the diversity of VOCs in cyclocephaline scarab-pollinated aroids.

KEYWORDS:

• Cyclocephala
• headspace sampling
• pollination
• volatile organic compounds

Acknowledgments

We thank David Scherberich for the permission to use his pictures from http://www.aroidpictures.fr/pictures.html in Figure 1 (b, d, f, and i). We are also grateful two anonymous reviewers for their constructive and improving comments on the manuscript.

Author contributions

MG: study conception, field observations, and manuscript writing.

EGG: access to the aroid collection of the Botanical Garden of the University of Brasilia, scent sampling, and plant identifications.

DMAF: host lab for the chemical analyses, identifications of several molecules.

ACDM: field observations, chemical analyses, and manuscript writing.

Disclosure statement

No potential conflict of interest was reported by the authors.