Investigating the altitude impact on the eco-phytochemical parameters of Ziziphora clinopodioides and Sophora alopecuroides in the different regions of northern Iran

Abstract

Various environmental factors such as altitude significantly affect the pharmacological and chemical properties of the plant. Here, the effect of three different altitudes of 1800 m (Rineh region), 2300 m (Polur region) and 2800 m (Lar region) above sea level on growth traits, yield and compositions of essential oil of two medicinal plants (Ziziphora clinopodioides Lam and Sophora alopecuroides L.) during two successive years (2018 and 2019) was investigated. The results showed that increasing the altitude from 1800 to 2800 m above sea level increased the morphological traits such as height, side branch number, root length and root volume, however, decreased the dry and fresh weight of both Ziziphora and Sophora plants. In Sophora plant, increasing the altitude enhanced the yield of essential oil and the highest yield of essential oil was obtained in Lar region. However, in Ziziphora, elevating the altitude from 1800 to 2300 m decreased the yield of essential oil, but further increase to 2800 m significantly increased the yield of essential oil. In Ziziphora, the highest amount of sophoramine, sophoridane and sophocarpine compounds was obtained at 1800 m, while the highest rates of adenocarpine, vinylphenol and matridin was obtained at 2800 m. For Sophora, the highest amount of sophoramine and vinylphenol was obtained at 2300 m, while sophocarpine showed the highest rate at 2800 m. Therefore, altitude is one of the important parameters of natural ecosystems that effectively change the quantitative and qualitative parameters of medicinal plants.