Investigations on Hoya species. VI. Latex composition and leaf phenolics and their taxonomic significance

Twenty five Hoya species were investigated for the possible use of the composition of latex triterpenes and leaf phenolics in their systematic identification. Both the phenolics (mainly apigenin-type flavones) and the latex triterpenes appeared rather specific for the species investigated. Because of its stability especially the latex particle composition may be worthwile as additional marker in the determination of Hoya species.