Postharvest Control of Green Mold Decay of Citrus Fruit Using Combined Treatment with Sodium Bicarbonate and Rhodosporidium paludigenum

The objective of this study was to analyze the impact of the marine yeast Rhodosporidium paludigenum and sodium bicarbonate (SBC) treatments applied separately or in combination to control green mold of two cultivars of citrus fruit (Citrus reticulata Blanco cv. Subcompressa and C. reticulata Blanco cv. Ponkan) caused by Penicillium digitatum. In the assay of C. reticulata Blanco cv. Subcompressa, R. paludigenum at 10(7) cells/mL significantly (P < 0.05) reduced green mold incidence compared to the control, and the combination of 10(7) cells/mL R. paludigenum and 5 % SBC was as effective as fungicide (500 ppm Fungaflor). In the assay of C. reticulata Blanco cv. Ponkan, the treatment with R. paludigenum at 10(8) cells/mL and 2 % SBC were equally effective and significantly (P < 0.05) reduced the decay incidence. Moreover, the combination of the two treatments completely eliminated the decay incidence, matching the effectiveness of fungicide. This work demonstrated that proper combination of R. paludigenum and SBC can be an alternative to synthetic fungicides for the control of postharvest green mold decay of citrus.