Comparison of Essential Oils Composition Between in-vitro Plantlets and Greenhouse Plants from Various Populations of Dracocephalum kotschyi Boiss

Dracocephalum kotschyi Boiss. belongs to the family Lamiaceae, a perennial herbaceous medicinal plant that is native to Iran and is considered an endangered species. In-vitro plantlets (seven populations) were raised in MS medium supplemented with 0.1 mg/l BAP and 0.01 mg/l NAA and the rooted plantlets were acclimatized successfully under greenhouse conditions. In- vivo plants (eight populations) were propagated under greenhouse condition. The essential oils were isolated by hydro distillation and identification of chemical compounds was done by a combination of capillary GC and GC-MS instruments. Twenty-five and forty compounds were identified in the different populations of in-vitro plantlet and in-vivo plant constituting 85.8%-99.68% and 85.1%-95.06% of essential oils, respectively. The major components of in-vitro plantlet on different populations were Verbenone (2.5%-82.47%), Geranyl acetate (28.35%-62.07%), Methyl geranate (0.98%-79.06%), Neral (0.64%-3.13%), Geranial (4.93%-14.39%), Limonene (0.37%-10.36%) and E-Anethole (7.62%-20.71%). The composition of essential oil from greenhouse plant populations were dominated by Neral (11.24%-74.80%), Limonene (0.17%-25.26%), Geraniol (0.54%-40.81%), Geranial (0.04%-9.15%), Methyl geranate (0.16%-28.48%), E-Anethole (0 %-0.1%) and Verbenone (0.39%-23.96%). The highest values of Neral, Limonene and Geraniol percentage were obtained from greenhouse conditions. In contrast, the maximum values of Verbenone, Geranyl acetate, Methyl geranate, Geranial, and E-Anethole were observed in the essential oils of in-vitro plantlets. This study demonstrated difference of chemical composition between in-vitro plantlets and greenhouse plants of different populations on D. kotschyi species. Also, new chemotypes of D. kotschyi has been introduced for further research.