B. Bahreininejad; M. Mirza
Abstract
Thymus daenensis Celak is one of the Iranian endemic plants. Since this species is one of the most valuable medicinal plants in the central Zagros region, extra-human exploitation has put it at risk of extinction. Ordination technique is one of the methods showing the relationship between plant and environmental ...
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Thymus daenensis Celak is one of the Iranian endemic plants. Since this species is one of the most valuable medicinal plants in the central Zagros region, extra-human exploitation has put it at risk of extinction. Ordination technique is one of the methods showing the relationship between plant and environmental variables. In order to study the effects of ecological variables on essential oil components, eight growing regions of Thymus daenensis in Isfahan province were identified and after collecting the aerial parts of plant materials, the essential oil was extracted and their components were detected. Twenty four bio-climatical, edaphical and topographical factors in each habitate were collected for ordination analysis. Results showed that elevation, mean temperature of the wettest season, isothermality, precipitation of the wettest season, annual precipitation, precipitation of the driest season and annual temperature range, clay, gravel, organic matter, available nitrogen and potassium were the most effective variables on the essential oil components. Thymol content as the main component in the essential oil was affected by annual temperature range, elevation, and slope. Soil sand percentage and the mean temperature of wettest quarter were the most effective variables on carvacrol. The result of this study could have valuable role in Thymus daenensis cultivation management in nature or farm regarding to its chemical components needed in the medicinal and hygienic industries.
J. Motamedi; E. Sofi Khajavi; A. Alijanpour; E. Sheidai Karkaj
Abstract
Study on the habitat characteristics of medicinal plants and estimating their production is one of the basic requirements for designing a future perspective document for utilization of by-products. Salep (Orchis palustris Jacq.) is one of the most important and highly valuable medicinal plants having ...
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Study on the habitat characteristics of medicinal plants and estimating their production is one of the basic requirements for designing a future perspective document for utilization of by-products. Salep (Orchis palustris Jacq.) is one of the most important and highly valuable medicinal plants having a significant distribution in the meadows of Targavar region of Urmia. Hence, among the meadows, six locations that were easier to reach and the distribution of Salep was more uniform were selected. In each location, using 60 plots of 60×25 cm2 that were randomly located within 10 plots with 10×1 m2, the number of Salep bases were counted and traits including crown cover percentage, plant height and tuber production were measured. Three composite soil samples from each location were randomly taken from the depth of root development of dominant species, and soil characteristics including sand, silt, clay, acidity, electrical conductivity, organic matter and total nitrogen were measured. The depth of groundwater (in each location) was considered as a criterion for moisture level and altitude, to analyze the relationship between habitat characteristics and plant traits. For this purpose, based on the calculated gradient length, the redundancy analysis (RDA) method was used as a linear method. The results of RDA showed that plant traits, especially tuber weight, were directly affected by the amount of organic matter, organic carbon, total nitrogen and clay percentage of the habitats. The mentioned traits are reversely related with altitude, groundwater depth and soil acidity of locations. In general, the Salep species more prefer low-altitude habitats such as alluvial plains with fertile, neutral acidity and heavy texture soils and high groundwater surface.
