the genus tanacetum l. is one of the most important medicinal plant that contains 28 species in iran, 12 of them are endemics. this paper reports the essential oil composition of tanacetum hololeucum (bornm.) podlech; tanacetum kotschyi (boiss.) grierson, growing wild in iran. plant flowers were collected from different zones of dizin in north of iran. all samples were hydro-distilled (clevenge...