Efficacy of volatile organic compounds by Aureobasidium pullulans immobilized on hydrogel spheres against strawberry fungal pathogens

Abstract

AbstractBACKGROUNDThe present study explores the use of two different growth supports for the biocontrol yeasts Aureobasidium pullulans M13, C10, R34 and P17, by use of nutrient yeast glucose (NYDA) agar and hydrogel spheres as the support matrix, then evaluates their impact on the production of volatile compounds (VOCs) and the subsequent in vitro and in vivo antagonistic activity against Botrytis cinerea and Colletotrichum acutatum.RESULTSFor the in vitro assay, VOCs secreted by the isolates C10 and M13 encased in the hydrogel spheres showed greater inhibitory activity on the mycelial growth of B. cinerea (70.30%) and C. acutatum (52.35%), respectively, with respect to NYDA. For solid‐phase microextraction‐gas chromatography‐mass spectrometry, VOCs produced by the selected yeasts immobilized in the hydrogel spheres or cultured in the agar were identified. VOCs were grouped as alcohols, ketones, alkane and aldehyde, with phenylethyl alcohol and 1‐propanol‐2‐methyl being the most prominently produced. The analysis revealed variations in both quantity and composition of VOCs among the growth supports, indicating the hydrogel spheres as enhancer distinct metabolic pathways and substrate utilization of the isolates, particularly in the M13 isolate.CONCLUSIONThe antifungal activity of the VOCs produced in the hydrogel spheres by the isolates C10 and M13 was assessed on strawberries, demonstrating a significant reduction in disease incidences. © 2024 Society of Chemical Industry.