Effect of biofertilizer and magnesium sulfate on the components of essential oil of Dracocephalum moldavica

In order to effect of biofertilizer and magnesium sulfate on the components of essential oil of Dracocephalum moldavica, an experiment was based on randomized complete block design with 6 treatments and 3 replications was performed. The factors consisted of barvar 2 fertilizer and non-inoculation and 3 levels spraying of magnesium sulfate (0, 2 and 4 g l−1). The results showed that barvar 2 biological fertilizer had significant effect on height, leaf length, stem width, aerial biomass yield, leaf yield and stem yield at 5% level. On the traits, number of tillers, stem diameter, branch number and essential oil yield were significant at 1% level. Also, there was no significant effect on leaf length and essential oil percentage. The highest aerial biomass yield was obtained by inoculation with barvar 2 and magnesium sulfate 4 g lit−1 with 6447 kg ha−1 and the lowest aerial biomass yield was obtained without inoculation and control treatment (2318 kg ha−1). The results showed that the highest essential oil yield was obtained by inoculation with barvar 2 (6.780 kg ha−1) and the lowest essential oil yield was obtained with 972.3 kg ha−1 for control treatment. In general, in order to produce more essential oil and to have more dry yield, it seems appropriate to inoculate with barvar 2 fertilizer and magnesium sulfate. •Non-inoculation and inoculation with barvar 2 biofertilizer used, improved essential oil yield of Dracocephalum moldavica.•0, 2 and 4 g lit−1 of magnesium sulfate used, improved essential oil yield of Dracocephalum moldavica.•Interaction effect of inoculation with barvar 2 × magnesium sulfate improved growth traits of Dracocephalum moldavica.