Control of fungal decay of apples and peaches by the biofumigant fungus Muscodor albus

Abstract The potential of the volatile-producing fungus Muscodor albus for controlling postharvest diseases of fresh fruit by biological fumigation was investigated. In vitro tests showed that M. albus volatiles inhibited and killed a wide range of storage pathogens belonging to species of Botrytis , Colletotrichum , Geotrichum , Monilinia , Penicillium and Rhizopus . Fumigation of apples for 7 days with culture of M. albus grown on autoclaved grain gave complete control of blue mold ( Penicillium expansum ) and gray mold ( Botrytis cinerea ) in wound-inoculated fruits. There was no direct contact between the fruit and the M. albus culture. Shorter fumigation times ranging between 24 and 72 h, applied immediately or 24 h after inoculation, also controlled blue mold and gray mold. In wound-inoculated peaches, 24–72 h fumigation with M. albus provided complete control of brown rot ( Monilinia fructicola ). The volatile profile of M. albus -colonized grain was measured by gas chromatograph connected to a flame ionization detector (GC-FID) and showed that 2-methyl-1-butanol and isobutyric acid were the major volatile compounds found in the headspace. Since M. albus is a sterile mycelium and does not require direct contact with the crops to be treated, it could be an attractive biological fumigant for controlling postharvest diseases.