Foliar spraying of salicylic acid induced accumulation of phenolics, increased radical scavenging activity and modified the composition of the essential oil of water stressed Thymus vulgaris L

Polyphenolic compounds are considered valuable secondary plant metabolites owing to the myriad of biological activities they exert. This study aimed to investigate the effect of applying various concentrations of the plant growth regulator, salicylic acid (SA), on Thymus vulgaris L. while subjecting the plant to decreasing amounts of irrigation water. The following parameters were monitored; total polyphenolic and flavonoid content, yield and composition of the essential oil, and antioxidant activity of the alcoholic extracts. Drought alone significantly (P