Control of postharvest decay on cherry tomatoes by marine yeast Rhodosporidium paludigenum and calcium chloride

Aims: In this study, the potential of calcium chloride (CaCl2) application to improve the efficacy of the marine antagonist Rhodosporidium paludigenum in controlling postharvest diseases of cherry tomatoes was assessed. Methods and Results: CaCl2 alone was found not to have any direct influence on the population growth of R. paludigenum in NYDB cultures or in cherry tomato wounds. However, the combined treatments with 1 × 108 cells ml−1R. paludigenum and CaCl2 at the concentration from 0·5 to 2% showed high activities to reduce black rot caused by Alternaria alternata in cherry tomato wounds, significantly higher than those of R. paludigenum or CaCl2 alone. Meanwhile, 0·5% CaCl2 in combination with 1 × 108 cells ml−1R. paludigenum greatly inhibited the natural decay of cherry tomatoes in 21 days' storage at 25°C. Conclusions: The combination of R. paludigenum and CaCl2 enhances the inhibition of black rot and natural decay of postharvest cherry tomatoes. The results from this study provide a new way to improve the efficiency of R. paludigenum in maintaining the quality of postharvest fruits and vegetables. Significance and Impact of the Study: The marine yeast R. paludigenum combined with CaCl2 has greatly potential use as an alternative to chemical fungicides in inhibiting postharvest decay on cherry tomatoes.