Postinfectional inhibitors from plants. VII. Tolerance of capsidiol by fungal pathogens of pepper fruit

摘要

Alternaria alternataandFusarium oxysporumwere isolated from field-grown peppers (Capsicum frutescensL.) and the antifungal sesquiterpene, capsidiol, was demonstrated inA. alternatalesions. In laboratory experiments, both fungi induced strongly antifungal diffusates and the activity was shown to be due to their content of capsidiol, or in the case ofF. oxysporumto a combination of capsidiol and capsenone. Growth of the non-pathogenMonilinia fructicolawas completely inhibited by theA. alternatediffusate at one-eighth and by theF. oxysporumdiffusate at one-quarter of the original concentration. The inducing fungi were also inhibited by their own diffusates 80 and 50 respectively but, in spite of this, effectively parasitized fruit tissue.