Tomato cv. ‘Micro-Tom’ as a model system to study postharvest chilling tolerance

Abstract

Storage at low temperature is a common practice to extend the market life of many vegetables. Among other horticultural crops, tomato fruit suffers chilling injury when it is storage under refrigerated conditions. Much effort has been made to understand the mechanisms of generation of this physiologic disturbance, but many aspects need to be clarified yet. Tomato (Solanum lycopersicum) cv. “Micro-Tom” is a miniature tomato plant with various properties that make it useful as a model system in plant biology. In this work, the potential of tomato cv. “Micro-Tom” fruit as a model to study chilling injury was investigated. The effect of postharvest chilling was compared on cvs. “Micro-Tom” and “Minitomato”, another variety with fruit of similar size. Green mature fruits cvs. “Micro-Tom” and “Minitomato” were harvested and stored during 4 weeks at 4°C. It was observed that tomato cv. “Micro-Tom” fruit was clearly tolerant to chilling while tomato cv. “Minitomato” fruit developed severe chilling injury symptoms and avoided ripening. Harvest and chilling altered the length of time between the different ripening stages, the development of red full color and smell. Also, it was shown that harvesting fruits by visual appreciation is a rapid and useful method for distinguishing the different ripening stages during tomato cv. “Micro-Tom” fruit ripening. These results showed that tomato cv. “Micro-Tom” fruit was able to counteract the strain resulting from the imposed chilling stress. Altogether these data indicate that tomato cv. “Micro-Tom” fruit is a good model to study the mechanism of postharvest chilling response and tolerance in tomato.