Inhibitory effect of citrus fruit essential oil components on Penicillium italicum and P. digitatum.
Essential oils, which are present in great quantities in the flavedo of citrus fruit, can exert an important bioregulatory effect on fungal spores of the 2 main postharvest pathogens of citrus fruit (P. digitatum and Penicillium italicum). As a part of a screening survey to investigate the bioregulatory activity of citrus fruit essential oils, an in vitro study was conducted to determine the activity of citrus fruit essential oil components nonanal, citral, alpha-pinene, myrcene, alpha-phellandrene and d-limonene on germination of P. digitatum and P. italicum spores by adding 1000, 500, 250, 125 p.p.m. of various compounds to sucrose agar. The most active compound, in relation to the method and to fungal strains employed, was citral which at 250 p.p.m. exerted a fungistatic action on both pathogens.