Study of some physiological traits, yield and essential oil contents of Dracocephalum kotschyi Boiss. in natural habitats of Bojnourd

Dracocephalum kotschyi Boiss. it is one of the medicinal and aromatic plants that can be found in natural habitats in mountainous and high areas of the country. This plant is very popular because of its large amounts of essential oil and important medicinal properties. In this study, in order to investigate the effect of the habitat on the physiological traits, yield and essential oil content, random sampling of the flowering branches of the plant in the full flowering stage with three replications was done from its natural habitats located in the altitudes of Espidan, Akher Dagh and Arkan in North Khorasan province. The results showed that the plants grown in Espidan region with 15.76 g F.W and 3.24 g D.W are the highest, and the plants of Akher dagh region with 12.58 g F.W and 2.68 g D.W, are the lowest in fresh and dry weight. In terms of the content of flavonoid compounds and the percentage of essential oil yield, the highest amount of these compounds was obtained from 69.63 (mg Q/g D.W) and 1.52% from the plants of Arkan heights. Further, the results showed that 23 compounds were identified in the essential oil of plants of three habitats, and the compounds of cis-α-Bergamotene, limonene and ß-ocimene were the main common compounds in the essential oils of three regions. In connection with the antioxidant property, the plants of Arkan area showed a higher antioxidant capacity than other habitats in inhibiting DPPH free radicals with 50.89 μg/ml. In terms of anthocyanin content, extract of Arkan plants with 2.96 mg of cyanidin 3-glucoside/g was a greater source of anthocyanin, with a significant difference compared to other plants. General conclusion The plants grown in the altitudes of Arkan showed more content of anthocyanin, flavonoid compounds, antioxidant capacity and essential oil yield than other habitats, and it seems that the Arkan habitat has the most suitable conditions for the cultivation of this valuable medicinal plant.