The aim of the present study was to determine the effect of high temperature stress (HT) and to evaluate the protective role of fungicide pretreatment against HT stress in tomato leaves. The oxidative stress was triggered under HT stress through an increase in the content of malondialdehyde (MDA) and hydrogen peroxide (H2O2). Also, it caused a decline in photosynthetic pigments and enhanced the proline in tomato. However, the activities of catalase (CAT; EC ), peroxidase (POX; EC ), and glutathione S-transferase (GST; ), as well as ascorbate-glutathione cycle enzymes (APX, EC , DHAR, EC , MDHAR EC , GR; EC ) were found to be increased after heat treatment. In addition, the transcript level of LeCAT1, LeAPX1, LeAPX6, LecGR, LeDHAR genes was up-regulated under HT stress. |