Efficacy of killer yeasts in the biological control of Penicillium digitatum on Tarocco orange fruits (Citrus sinensis)

► Killer strains of Wickerhamomyces anomalus effectively control Penicillium digitatum. ► The synthesis of β-glucanases may explain their efficacy against the pathogen. ► The killer activity was evidenced at pH value of the injured or wounded citrus fruit. ► The incidence and severity of green mould disease were significantly reduced on fruits.