Abstract: In this study, the effect of peptide Jelleine-I (antimicrobial peptide derived from royal jelly) on the growth of Penicillium digitatum and its possible mode of action were investigated. Meanwhile its effect on the control of postharvest green mold induced by stab inoculation in citrus fruit was evaluated. The results showed that Jelleine-I could significantly inhibit the growth of P. digitatum. The minimal inhibitory concentration and minimal fungicidal concentration were 6.25 and 12.5 μmol/L, respectively. Jelleine-I could significantly decrease the incidence of green mold of citrus fruit. After being treated with Jelleine-I, the membrane permeability of P. digitatum hyphae increased and the intercellular membrane was damaged. The intracellular green SYTOX Green fluorescence increased and the intercellular blue Calcofluor White fluorescence decreased. In addition, Jelleine-I significantly increased the extracellular conductivity and the intracellular leakage of nucleic acid (P < 0.05). Therefore, Jelleine-I could effectively control citrus postharvest green mold by damaging the membrane structural integrity and consequently causing intracellular material leakage and accelerating the death of P. digitatum.

Key words: Jelleine-I, postharvest diseases, citrus fruit, green mold, control effect