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

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-beta-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.

Automated summary

This study characterized the floral scent chemistry of nine species of Philodendron in French Guiana, identifying 43 volatile organic compounds (VOCs). The floral blends varied in the number of constituents, but each blend could be summarized into one to four major constituents. The floral scent compositions significantly differed among the species.