Chemical Composition and Antifungal Activity of Essential Oils of Rosmarinus officinalis L. and Salvia officinalis L. against Botrytis cinerea Pers

Abstract

Botrytis cinerea Pers. the causative agent of grey mould is commonly controlled by synthetic fungicides. Recently, studies have focused on the use of aromatic and medicinal plant extracts as safer alternatives. The aim of this study was to investigate the chemical composition and the antifungalactivity of essential oils of Rosmarinus officinalis L.(REO) and Salvia officinalis L.(SEO), against B. cinerea Pers.on tomato leaves and fruits. The EOs were extracted by hydrodistillation, and their chemical composition was analysed by gas chromatography-mass spectrometry (GC-MS). The antifungal activity of the EOs was evaluated on tomato leaves and fruitsinfested with B. cinerea Pers. using four treatment methods; simultaneous, preventive, curative, and combined preventive and curative treatments. GC-MS analysis showed that REO is composed mostly of α-pinene (29.01%), verbenone (21.59%), and camphor (7.32%), while SEO is predominantly composed of trans-thujone (29.01%), 1,8-cineole (22.78%), camphor (20.31%), and α-pinene (7.49%). REO and SEO demonstrated a concentration-dependent antifungal activity against B. cinerea Pers, especially in the combined preventive and curative treatment which exhibited 100% fungal growth inhibition for both EOs on tomatoleaves and fruits. On the tomato leaves, REO showed the least antifungal activity in the simultaneous treatment (IC50= 7.62 ± 0.83µL/mL), while on tomato fruits, the curative treatment withSEOexhibited the least effective activity (IC50= 9.15± 0.53µL/mL). Therefore, the essential oils of R. officinalis and S. officinalis. have potential for use in the biocontrol of tomato grey mould under green house and postharvest storage.