Antifungal activity of essential oils associated with carboxymethylcellulose against Colletotrichum acutatum in strawberries

Abstract

The antifungal activity of the essential oils (EOs) of Eucalyptus staigeriana, Lippia sidoides and Pimenta pseudocaryophyllus was evaluated in vitro, by direct contact and by exposure to volatiles, against Colletotrichum acutatum, an important pathogen of strawberry. The chemical composition of the EO with the highest activity and its effects on the morphology of the pathogen were verified. The in vivo antifungal activity of this EO associated with carboxymethylcellulose (CMC) coating, in preventive and curative applications, was also evaluated. L. sidoides EO presented the highest antifungal activity in vitro, being more efficient by direct contact than by volatilization. This EO has a predominance of the compound thymol and was able to cause dehydration and rupture of the pathogen hyphae. In vivo, strawberries treated with CMC associated with L. sidoides EO presented a reduction in disease severity, when treated in a curative way. Thus, the association of L. sidoides EO with CMC can be a potential alternative for the control of this disease.