Mycofumigation with Oxyporus latemarginatus EF069 for control of postharvest apple decay and Rhizoctonia root rot on moth orchid.

AIMS: To characterize the volatile antifungal compound produced by Oxyporus latemarginatus EF069 and to examine in vitro and in vivo fumigation activity of the fungus.

METHODS AND RESULTS: An antifungal volatile-producing strain, O. latemarginatus EF069 inhibited the mycelial growth of Alternaria alternata, Botrytis cinerea, Colletotrichum gloeosporioides, Fusarium oxysporum f. sp. lycopersici, and Rhizoctonia solani by mycofumigation. An antifungal volatile compound was isolated from the hexane extract of wheat bran-rice hull cultures of O. latemarginatus EF069 by repeated silica gel column chromatography and identified as 5-pentyl-2-furaldehyde (PTF). The purified PTF inhibited mycelial growth of R. solani in a dose-dependent manner. The mycofumigation with solid cultures of EF069 also reduced effectively the development of postharvest apple decay caused by B. cinerea and Rhizoctonia root rot of moth orchid caused by R. solani.

CONCLUSIONS: Oxyporus latemarginatus EF069 showed in vitro and in vivo fumigation activity against plant pathogenic fungi by producing 5-pentyl-2-furaldehyde.

SIGNIFICANCE AND IMPACT OF THE STUDY: Oxyporus latemarginatus EF069 producing an antifungal volatile compound may be used as a biofumigant for the control of fungal plant diseases.