evaluation of ecotype and chemotype diversity of thymus daenensis celak. on isfahan and chaharmahal va bakhtiari provinces

background & aim: thymus daenensis celak. is one of the herbal and  perennial medicinal plants belonging to lamiaceae which grows widely in isfahan and chaharmahal va bakhtiari provinces. all of its floral on aerial part has extensive use in preparing traditional medicines. the major constitutes of thymus daenensis celak. are thymol and carvacrol. since ecological conditions have a great role in growth of the plant, and on the quality and amount of effective material in medicinal plants, this study tries to investigate on the effect of ecological factors included geographical factors, climatic and edaphic factors. martial & methods: this study was collected from 22 different regions in isfahan and chaharmahal va bakhtiari provinces. the composition was determined using high performance liquid chromatography. hplc chromatograms showed the amount of thymol and carvacrol in every region. results & discussion: the highest content of thymol in all investigated samples was recorded in sheikhshaban region (35.89 mg/g methanol extract) (altitude 2747 m asl) and highest content of carvacrol was recorded in lark region (23.53 mg/g methanol extract) (altitude 2370 m asl). the results of regression showed that altitude has a positive and meaningful effect on the amount of thymol and does not effect on the amount of carvacrol. all other edaphic factors and climatic factors have no significant effect on the amount of thymol and carvacrol. cluster dendrogram analysis of the under study regions was drawn according to 3 parameters: the amount of thymol, the amount of carvacrol and the height of the plant (cm), showed the rate of relatedness in samples of different regions, in separate clusters. conclusion: thymus daenensis celak. in sheikhshaban and lark in chaharmahal va bakhtiari have a close  relationship among themselves that have highest amount thymol and carvacrol.