Biocontrol of postharvest green mold of oranges by Hanseniaspora uvarum Y3 in combination with phosphatidylcholine

Abstract

The effect of phosphatidylcholine (soybean extract) on the biocontrol efficacy of the antagonistic yeast Hanseniaspora uvarum Y3 against green mold of oranges was investigated. The results showed that H. uvarum Y3 significantly inhibited green mold of oranges at different concentrations compared with the control. Besides, phosphatidylcholine was observed to enhanced the biocontrol efficacy of H. uvarum Y3. Among the different concentrations, phosphatidylcholine at 1.5% w/v combined with H. uvarum Y3 exhibited the best control effect, the green mold incidence of oranges was only 4.63%, while the incidence was 33.33% when treated with H. uvarum Y3. After 24h incubation, phosphatidylcholine at the different concentrations did not significantly influence the population of H. uvarum Y3 in NYDB. However, it was found that, phosphatidylcholine (1.5% w/v) significantly improved the population dynamics of H. uvarum Y3 in orange wounds at 20°C. The scanned electron microscope (SEM) results showed that H. uvarum Y3 combined with phosphatidylcholine (1.5% w/v) significantly inhibited the spore germination and mycelial growth of Penicillium digitatum in orange wounds. Moreover, H. uvarum Y3 in combination with 1.5% phosphatidylcholine treatment did not impair postharvest qualities of oranges. Conclusively, H. uvarum Y3 in combination with phosphatidylcholine offers a great potential as an alternative method against postharvest green mold of oranges.