Foliar Application of Salicylic acid Changes Essential oil Content and Chemical Compositions of Peppermint (Mentha piperitaL.)

Abstract

Salicylic acid (SA) is a naturally occurring plant hormone influencing various physiological and biochemical functions in plants. This investigation was conducted to evaluate the effects of different concentrations (0, 75, 150, 300, 450 mgL^-1) of salicylic acid (SA) on the essential oil (EO) content and compositions of peppermint (Mentha piperita L.). The results showed that application of 150 mgL^-1 SA significantly (p<0.05) increased the oil content compared to control plants. However, the EO components were not drastically changed by different SA treatments. In total, 33 compounds were detected in the EO samples of peppermint treated with different SA concentrations with menthone (15.8-18.1 %), menthol (46.3-47.4 %), methyl acetate (8.5-9.7 %) and 1,8-cineole (4.3-4.6 %) being the major ones.