The biosystematics of the section Drosanthe (Spach) Endl. belong to genus Hypericum L. (Hypericaceae)

In this study, taxa of the section Drosanthe (Spach) Endl. belong to genus Hypericum L. of Turkey were evaluated by means of morphological, anatomical, palynological and chemical data. Habitat features, IUCN categories and geographical distributions of the species were also given with species identification keys of morphological and chemical. In the anatomical studies the anatomies of stem and leaf, root of taxa were examined. The shape of the pollens of all Drosanthe taxa studied were determined as prolate spherodial, type of aperture were tricolporate and ornementation were reticulate. The essential oil composition of Drosanthe samples obtained by hydro-distillation were determined by using GC and GC-MS system. Oil yields of Drosanthe taxa were determined as range of 0.5%-0.9% (v/w). ? -pinene (4.08%-58.02%), ? -caryophyllene (1.05%-23.92%), caryophyllene oxide (2.86%-16.34%), nonacosane (1.22%-23.84%), undecane (1.00%-19.24%), ? -3-carene (1.17%-25.18%) and camphor (1.03%-32.40%) were detected as the main compounds of Hypericum taxa. According to the numerical analysis, while the morphological grouping of the Hypericum taxa in this section were showed congruency with the morphological description in Flora of Turkey but more differences were determined in the chemical dendrogram grouping of the taxa studied.