Study on the antimicrobial components and mechanism of citronella essential oil against Botrytis cinerea

The excessive use of fungicide has not only led to widespread resistance in plant pathogens but has also posed significant health risks to humans due to pesticide residues. Plant essential oils have emerged as a focal point in research on green fungal control strategies due to their broad-spectrum antimicrobial activity. This study evaluated the antifungal effects of nine plant essential oils against Botrytis cinerea . The results indicated that citronella ( Cymbopogon winterianus Jowitt) essential oil exhibited the most potent inhibitory effect. Compound analysis and antimicrobial tests revealed that citronellol is the active antifungal component in citronella oil. At a concentration of 200 μL/L, citronellol achieved a 76.93% inhibition rate. This study, for the first time, elucidates the mechanism of action of citronellol monomer against Botrytis cinere a through a combination of in vivo and in vitro experiments: disrupting cell membrane integrity to alter permeability and inducing elevated hydrogen peroxide levels. These findings provide a theoretical basis for the development of new green control approaches.