Experimental study of the structure of variability of natural populations of Origanum vulgare L. from mountainous Dagestan, Russia

Aim . To identify plasticity and stability and to evaluate interpopulation differentiation in terms of accumulation of secondary metabolites in an ecological and geographical experiment with two model populations of Origanum vulgare L., belonging to different subspecies and vicarious along the altitudinal gradient. Material and Methods . Ecological and geographical experiment with transplanted plants of Origanum vulgare L. at two experimental bases, at altitudes of 1100 and 1730 m and simulating the conditions of the mountain‐valley and upper mountain belts. The total content of antioxidants was determined by the electrochemical method. The essential oil was obtained by hydrodistillation on a Clevenger apparatus. The component composition of the oil was established on a gas chromatograph with a mass spectrometric detector. Components were identified using mass spectra libraries. Results . We studied the structure of variability in the yield and component composition of essential oil, as well as the total antioxidant activity in two populations of Origanum vulgare L. belonging to different subspecies. Regularities have been revealed that make it possible to attribute the studied populations to foothill and highland ecotypes. Conclusions . The yield of essential oil and the content of total antioxidants are clearly correlated with the conditions in the experimental plots and are not associated with microevolutionary processes under the control of abiotic factors of the altitudinal gradient.