The biosystematics of some taxa belongs to genus Helichrysum Mill.

In this study, some taxa of the belong to Helichrysum Mill. of Turkey were evaluated by means of morphological, anatomical, palynological and chemical data. Habitat features, threatened categories and geographical distributions of the species were given. The morphological characters were compared with Flora of Turkey and added some new morphological characters. In the anatomical studies the anatomies of the stem and leaf, root of taxa were examined. The shape of the pollens of Helichrysum of Helichrysum chionophilum Boiss.&Bal., Helichrysum noeanum Boiss., Helichrysum arenarium (L.) Moench subsp. aucheri (Boiss.) Davis et Kupicha, Helichrysum plicatum DC. subsp. polyphyllum (Ledeb.) and Helichrysum graveolens (Bieb.) Sweet were determined as oblate spheroidal and plicatum subsp. plicatum was determined as spheroidal, type of the aperture were ticolporate and ornementation were echinate. The essential oil composition of Helichrysum samples obtained by hydro-distillation were determined as range of 0.5%-1% (v/w). Usually (E)-Caryophyllene (%6.91-%7.44), ? -cubebene (%1.61-%9.50), ? -gurjunene (%1.38-%11.06), zonarene (%2.00-%5.79) and 1,8-cineole (%41.72) were detected as the main compounds of Helichrysum taxa. According to the numerical analysis, while the morphological grouping of the Helichrysum taxa 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.Key Words Helichrysum, morphology, anatomy, pollen, essential oil, biosystematics, chemotaxonomy.