Effect of Headspace and Trapped Volatile Organic Compounds (VOCs) of the Chinese Caterpillar Mushroom, Ophiocordyceps sinensis (Ascomycetes), against Soil-Borne Plant Pathogens.

Abstract

Headspace volatile metabolites produced by Ophiocordyceps sinensis were tested against soil-borne plant pathogens (namely, Fusarium oxysporum f. sp. lycopersici, F. oxysporum f. sp. cubense, Thanatephorus cucumeris, Athelia rolfsii, and Macrophomina phaseolina). Diffusible volatile metabolites produced by O. sinensis inhibited 52% and 48% of the mycelial growth of F. oxysporum f. sp. lycopersici and F. oxysporum f. sp. cubense, respectively. In addition to inhibiting mycelial growth, the headspace volatile metabolites also induced several morphological changes in the culture characteristics and mycelia of the tested fungi. Stunted and depressed colony growth was observed for F. oxysporum f. sp. cubense and F. oxysporum f. sp. lycopersici. The headspace volatile compounds produced by O. sinensis were trapped in a glass cartridge (Porapak Q). The trapped compounds were eluted from the column by using hexane and then, by using gas chromatography-mass spectrometry, were identified as tetratetracontane, 1(2H)-naphthalenone, 3, 4-dihydro-3-methyl, 3-hexenoic acid, 1-methyl-3-ethyladamantane, and phenol, 3-ethyl.