Intermittent warming during low temperature storage reduces tomato chilling injury

Long term low temperature storage of mature-green tomatoes is currently risky because of the likely development of chilling injury (CI), reducing shelf life and hence restricting flexibility of trade. Intermittent warming (IW) has been proposed as a potential solution to aid successful long term tomato storage. The effectiveness of an IW regime in reducing CI was tested in two different tomato cultivars each grown in a different production conditions (Palmerston North, New Zealand and FL, USA) and stored at low temperature. Three cycles of IW to 20 °C for 24 h every 7 d reduced CI and decay development in fruit stored at either 2.5 or 6 °C for 27 d. However, efficacy of IW differed greatly between the two cultivars/production regions. Cycles of IW enhanced red colour development in New Zealand greenhouse-grown ‘Cedrico’ tomatoes stored at 6 °C, while the same cycles in field-grown ‘Soraya’ tomatoes in Florida did not. Decay severity was higher in ‘Soraya’ and occurred at both 2.5 and 6 °C, whereas ‘Cedrico’ showed decay at only 2.5 °C. However, IW reduced decay incidence in tomatoes from both locations. While IW was effective in reducing CI in both cultivars/production regions, these results suggest that CI symptoms and IW efficacy are highly dependent on cultivar and/or production conditions.

► Different chilling injury symptoms in tomatoes have independent responses to intermittent warming.
► Intermittent warming stimulates ethylene production in cool storage.
► Intermittent warming reduces chilling induced decay independent of ethylene production.
► Intermittent warming efficacy is dependent on cultivar and/or production conditions.