The effect of substrate, organic matter, and salinity on the contents of essential oil and active ingredients of lemon balm (Melissa officinalis L.).

To investigate the effect of substrate, organic matter, and salinity on the amount of essential oil and active ingredients of lemon balm (Melissa officinalis L.) a factorial experiment was conducted in a completely randomized design. Based on the results, the highest percentage of essential oil was observed in the combined substrate of arable soil + compost + vermicompost. The highest percentages of compounds including Trans-carveol, Isoborneol, and Carvacrol acetate were observed in the salinity of 80 mM in the combined substrate of arable soil + compost + vermicompost. The highest percentage of compounds including citronellol and γ-Terpinene were recorded under compost substrate. In the control and with a combined substrate of arable soil + compost, the highest percentage of compounds, including 1,3,8,-P-menthatriene was observed. Application of HA could increase the main constituents, including Trans-carveol, γ-Terpinene, Isoborneol, Citronellol, and Carvacrol acetate in lemon balm.