The investigationof Climate, Soil and Height On essential oil composition of essential oils of Oliveria decumbens Vent. Medicinal Plantfrom different regions in City Mamasani of Fars Province

Oliveria decumbens Vent is a medicinal plant belongs to the Umbelliferae family. According to the Iran traditional medicine comments this plant is used for the treat of indigestion, diarrhea, relieve fever and infectious diseases. In this research, effects of climate factors, soil and the elevation above sea level were tested on the chemical compounds of O. decumbens. To this, the flowering branches of O. decumbens were taken from 1600-2200 a.s.l. in the Mamassani County in May and air dried. The Clevenger apparatus extraction was used to extract the essence. The chemical compounds were identified using GC and GC/MS and the effect of studied parameters on chemical components were determined. Our result indicated that, there are 13, 16 and 11 chemical compounds in Doshman Ziari, Bavan and Koupen sites, respectively. p-cymene γ-terpinene، thymol and myristicin identified as the main compounds of studied sites. There was significant correlation between the annual precipitation and e elevation above sea level with the essence percentage and chemical compounds of O. decumbens . Furthermore, soil electrical conductivity, acidity and nitrogen had positive significant correlation (p < 0.05) with the percentage of essential oil.