Study of Edaphic, Morphological and Phytochemical Components of Wild Population of Otostegia persica B. in Habitats of Baluchistan, Iran

 One of the most important factors affecting the quantitative and qualitative characteristics of plants are genetic and environmental factors and their interactions. Golder (Otostegia persica Boiss.) is one of the endemic species of Iran and is in the list of top 10 medicinal plants used in Baluchistan, Iran. Therefore, in this study, some morphological and phytochemical characteristics of this plant were investigated in the natural habitats of Baluhistan. Essential oil components of leaves and flowers of Kooh birk-Mehrestan population also measured. Also, with the aim of investigating the soil properties on the establishment and growth characteristics of Golder, the soil edaphic characteristics of plant communities were evaluated.

 This study was conducted in 2017 in some natural habitats of Baluchistan, Iran. Research was performed in the form of a nested plan as completely random design with three replications in the cities of 1- Saravan (Villages of Kooh Sont and Nahuk), 2- Khash (Villages of Panj Angisht and Posht Kuh), 3- Sarbaz (Padik village and Kalat Sarbaz) and 4-Mehrestan (Villages of Zard and Birk kooh) using field survey. Edaphic traits such as soil texture and chemistry were measured. Morphological traits including plant height, internode distance, leaf length and width were measured using instruments such as graduated rulers and calipers. Phytochemical traits including Phenol, Flavonoids and Carbohydrates in different parts of the plant and also the components of essential oils in leaves and flowers were studied. Soluble carbohydrate by Coles and Ansel method, photosynthetic pigments by Arnon method, total phenols with fullene-cicalto reagent by McDonald method, Flavonoids by aluminum chloride colorimetric method and adsorption of any reaction compound at 415 nm wavelength by spectrophotometer were measured. Data analysis was performed by SAS software (version 9.2) and the means were compared by Duncan's multiple range test at 5% level.

 The lowest (7.80) and highest (8.50) pH levels were measured in Zard and Kooh Birk respectively. Lowest (1.29) and highest (4.38) EC levels in Panj angosht and Nahuk respectively, the lowest (43.53(dS m-1)) and highest (50.73(dS m-1)) Na levels in Kooh Birk and Nahuk respectively, the highest N (11.10%) and P (0.32 (ppm)) in the Posht kooh of Khash, the highest amount of total K (62.20 (ppm)), absorbable K (72.17(ppm)) and the highest percentage of silt (38.30) were obtained in the Kooh sont area of Saravan. In evaluating the growth characteristics of plant in different regions, the maximum internode distance, highest number of lateral branches, petiole length, leaf length and width and number of main branches in Kooh Birk region of Mehrestan city and highest plant height in Nahuk region of Saravan city were measured. Comparing the amount of phytochemical compounds in different organs of this plant, it was observed that the highest amount of flavonoids is present in the leaves and the highest amount of phenols and carbohydrates are present in the stem. The lowest amount of all three compounds was measured at the root. Maximum amount of leaf Flavonoids (1.83 mgQE/g), stem Phenol (mg GAE/g 1.86) and root Flavonoid (0.11 mgQE/g) in Panj angosht area of ​​Khash city, stem and root Flavonoids (0.45mgQE/g and 0.11mgQE/g) and stem Carbohydrate (1.99 mg/g) in Zard area of ​​Mehrestan city, leaf Phenol (mgGAE/g 2.38) and root carbohydrate (1.73 mg/g) in Posht kooh region of Khash, and maximum amount of leaf carbohydrates (1.99 mg/g) in Kooh sont area of Saravan were obtained. Analysis of the chemical composition of the essential oil using a gas chromatograph-mass spectrometer (GC-MS) showed 12 compounds per leaf and 31 compounds per flower. The highest and lowest essential oil components were Thymol (12.0%) and Decane (2.1%), respectively. Also, the highest and lowest components of essential oils in flowers were Benzene, 1- (1,5-dimethyl-4-hexenyl) -4-methyl- (CAS)) (13.0%) and (0.4%), respectively. Therefore, the lowest essential ingredient was Decane, both in leaves and flowers. In general, the results of this study showed that there is a considerable diversity among the studied populations in terms of all the studied characteristics. This indicates that environmental factors similar to genetic factors are effective in creating diversity in morphological and phytochemical characteristics of this plant.

 In general, the results of this experiment showed that the habitats of Khash are better in terms of soil chemistry and major phytochemical traits. Kooh birk region is the best area for harvesting the aerial parts of this plant.