Antifungal Activity of Propolis Extracts against Postharvest Pathogen Phlyctema vagabunda

Phlyctema vagabunda is one of the main postharvest pathogens in late-harvest apples in Chile. The control of this pathogen is mainly through synthetic fungicides or copper-based compounds; however, there are concerns about the residues of these products in food and the environment. Therefore, there is a need for seeking alternative control strategies, in which propolis, a resinous substance collected by bees with antimicrobial properties, could be an environmentally friendly and safe alternative to control for P. vagabunda. The aim of this study was to characterize and determine the pathogenicity of Chilean isolates of P. vagabunda and to evaluate the antifungal activity of propolis against P. vagabunda in vitro and in vivo conditions. The Chilean isolates were identified as P. vagabunda through morphological and molecular characterization. The concentrations of propolis of 0.5% and 0.05% significantly decreased the mycelial growth and germination of conidia by 88.5% and 100%, respectively. The incidence and severity of the disease in apples also decreased by 57.2% and 61.3%, respectively. The use of propolis extract could be a promising alternative for the control of P. vagabunda in apples.