Abohassan Farhang Sardrodi - Medicinal plants M Sc student, Department of Horticultural Sciences, University of Zanjan, Iran
Azizollah Kheyri - Faculty Member of Department of Horticultural Sciences, University of Zanjan, Iran
Ali Soleymani - Head of Department of Horticultural Sciences, University of Zanjan, Iran
Ramin Zibaseresht - Faculty Member of Imam Khomeini University for Naval Sciences of Nushahr, Mazandaran, Iran

Yarrow (Achillea spp.) belonging to the family of Asteraceae with useful properties, such as anti-diaphoretic, anti-hemorrhagic, anti-inflammation, anti-biotic, anti-fungal, anti-bacterial, Carminative and anti-oxidant effects. The present investigation assessed the morphological diversity of Achillea aucheri, which is indigenous plant from Damavand mountain of Iran. The samples were collected from five heights of Damavand and the morphological traits were studied. For estimating the percentage of essential oil, aerial parts were collected and oil was isolated by hydro distillation using Clevenger-type apparatus. The results of present study demonstrated that the highest plant height, internodes, biomass and number of leaves per node obtained at lowest altitude (۳۹۰۰ meters from sea level). In addition, fresh weight and dry weight of plant had the highest amount in altitude of ۳۹۰۰ meter from sea level. But essential oil content increased from low altitude to high altitude from ۰.۶۸۱% to ۰.۹۵۴%. Also high altitude had high significantly differences on the essential oil content. It revealed that plants in lower altitudes produce more biomass than higher altitudes, but essential oil content of plants was more in higher altitudes. It seems that a part of photosynthetic energy of plants in higher altitudes expend to produce secondary metabolites especially essential oils to overcome stress and survival in inappropriate conditions.

Achillea aucheri, Morphology, essential oil content, Altitude, medicinal plant