Postharvest chilling induces oxidative stress response in the dwarf tomato cultivar Micro-Tom

MALACRIDA, C.; VALLE, E. M.; SILVANA BEATRIZ BOGGIO

PHYSIOLOGIA PLANTARUM

Blackwell Publishing

Año: 2006 vol. 127 p. 10 - 18

0031-9317

Oxidative stress is involved in the response of Lycopersicon esculentum fruits(cultivar Micro-Tom) to chilling. Changes in activated oxygen scavengingenzymes, superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC1.11.1.6), ascorbate peroxidase (APX, EC 1.11.1.11), and glutathione reductase(GR, EC 1.6.4.2) were examined during ripening after postharvest chilling.Also, lipid peroxidation, respiration, and pigment contents weredetermined. These parameters were affected by chilling, especially the lycopenecontent and the respiration rate that showed a high value when thefruits were transferred to higher temperatures. CAT activity increased the dayafter the fruits were re-warmed, while the activity of GR was higher in thechilled than in the non-chilled green fruits. Lipid peroxidation was moreevident at the ‘pre-chilled’ yellow and red fruits. APX and SOD were notaffected by previous chilling in ripening fruits. These results indicate thatoxidative stress is generated by conservation at 4C. The antioxidantresponse of tomato fruit could be mediated by CAT and GR but not bySOD or APX. Moreover, CAT seemed to respond to the increase in therespiration rate.