EFFECT OF POSTHARVEST HEAT-TREATMENT OF TOMATOES ON FRUIT RIPENING AND DECAY CAUSED BY BOTRYTIS-CINEREA

Holding inoculated mature green and pink tomato fruits for 3 days at 38 C completely inhibited decay caused by Botrytis cinerea, one of the main postharvest pathogens of tomatoes in Israel. Conidial germination was more sensitive than mycelial growth to 38 C, but inhibition of both processes increased with duration of treatment. The prophylactic effect of heating on decay of tomatoes caused by B. cinerea appeared to be by direct interaction with the fungus rather than by inhibitory effects on fruit ripening. Carbon dioxide production by tomatoes increased and ethylene production decreased during heating, but when fruit were moved to 20 C, gas evolution rates returned to those of nonheated fruit. Heating did not affect tomato firmness, color, soluble solids content, or acidity by the end of 7 days at 20 C. Prestorage heating may be a useful nonchemical method of controlling postharvest pathogens.