THE EFFECTIVENESS OF POSTHARVEST HOT-WATER DIPPING ON THE CONTROL OF GREY AND BLACK MOLDS IN SWEET RED-PEPPER (CAPSICUM-ANNUUM)

The effectiveness of hot water dipping on the control of grey mould, c aused by Botrytis cinerea, and black mould, caused by Alternaria alter nata on sweet red pepper quality was investigated. Dipping naturally i nfected or artificially inoculated fruit at 50 degrees C for 3 min com pletely inhibited, or significantly reduced, decay development caused by B. cinerea and A. alternata, respectively. Heat damage was observed on fruit dipped for 5 min at 50 degrees C, or at 55 degrees C for 1 m in or longer. Damage appeared as cracks and pitting on the fruit surfa ce. Spore germination and germ tube elongation in vitro was inversely related to the duration of exposure or to the range of temperature use d. The ET(50) for spore germination for B. cinerea was 3.2, 1.5 and 0. 8 min, and for A. alternata 8.8, 4.2 and 1.4 min, at 45, 50 and 55 deg rees C, respectively. The ET(50) for germ tube elongation for Botrytis was 2.6, 0.9 and 0.5 min, and for Alternaria, 7.2, 2.5 and 1.6 min, a t 45, 50 and 55 degrees C. The mode of action of hot water dips on dec ay of pepper appears to be by direct interaction with the fungi.