Effect of volatiles on mycelium growth of Penicillium digitatum, P-italicum, and P-ulaiense

More than 200 mono- and sesquiterpenes were evaluated by agar diffusion plate tests for their ability to inhibit the growth of three postharvest pathogenic fungi: Penicillium digitatum, P. italicum, and P. ulaiense. Major fungicidal action was observed in phenolic components like carvacrol and related homologue molecules. Etherified components like anethole, methyl chavicol and safrole exhibited less fungicidal action. Monoterpene hydrocarbons gave poor results. Fungicidal action against the three species often differed in degree of strength. Some components showed a strong fungicidal as well as fungistatic action, others only a fungistatic action. The inhibition of many components lasted for several months. In others a regression was observed as early as one week after initial scoring.