Effects of Carbon Monoxide on Decay, Physiological Responses, Ripening, and Composition of Tomato Fruits1

Abstract

Abstract CO (5 and 10%) + 4% O 2 atmospheres retarded growth of Botrytis cinerea Pers. ex Fr. ( in vitro ) and reduced decay incidence and severity on inoculated tomatoes ( Lycopersicon escuientum Mill.) harvested at the mature-green (MG) or pink (P) stage and held at 12.5°C for up to 14 days (MG) or 10 days (P). This reduction was still evident after holding for an additional 2 to 3 days (P) or 7 days (MG) at 20° in air. CO + 4% O 2 atmosphere was more effective than CO + air atmosphere in all experiments. CO + air treatments increased CO 2 and C 2 H 4 production rates and hastened ripening of MG fruits, while CO + 4% O 2 atmosphere had no or very small effect on these physiological responses relative to 4% O 2 atmosphere at 12.5°. After transfer to air at 20°, fruits previously exposed to CO exhibited slightly higher CO 2 and C 2 H 2 production and faster ripening than control fruits. CO added to air or 4% O 2 did not affect ripening rate of fruits picked at the breaker, turning, or pink stages. CO + air or 4% O 2 atmosphere slowed down softening of pink fruits during a 7- or 14-day storage period at 12.5°. Fruits subjected to CO + 4% O 2 for 7 days maintained their sugar and acid content better than control fruits.