Effects of preharvest applications of CaCl2, 2,4-d and benomyl and postharvest hot water, yeast and fungicide treatments on development of decay on satsuma mandarins

In this study, an integrated approach was evaluated for the control of postharvest decays of mandarin including some pre- and post-harvest treatments under storage conditions. The efficacy of the treatments both as alone and in combination was evaluated during 3 years. Preharvest application of benomyl resulted in significantly less decay of mandarin fruit after storage in 3-year tests. Calcium chloride (CaCl2), 2,4-dichlorophenoxyacetic acid (2,4-D) and gibberellic acid (GA(3)) as stand-alone treatments or combinations were not effective in controlling Penicillium and total decay infections on inoculated mandarin. Postharvest application of imazalil (200 mug/ml) in solution heated to 54degreesC for controlling postharvest green and total decay of mandarin was significantly effective for 3 months under storage conditions. The biocontrol activity of yeast (Metschnikowia pulcherrima) was improved when yeast treatment was combined with imazalil (200 mug/ml) at postharvest. The data suggest that preharvest application of benomyl and postharvest treatments of imazalil, hot water and yeast may reduce postharvest green mould and total decay of mandarin under storage conditions.