Activities of antioxidant enzymes. Changes in enzyme activities of ascorbate peroxidase (APX; A), monodehydroascorbate reductase (MDHAR; B), dehydroascorbate reductase (DHAR; C), glutathione reductase (GR; D), catalase (CAT; E), superoxide dismutase (SOD; F), and peroxidase (POX; G) based on protein content and fresh weight during ripening in ‘Santorini’ and ‘Ailsa Craig’ fruits grown in a hydroponic system in the greenhouse. Ripening stages are expressed as Days After Pollination (DAP). For ‘Santorini’: 27DAP, immature green (IG); 38DAP, mature green (MG); 40DAP, B-1; 41DAP, breaker (B); 42DAP, B + 1; 46DAP, pink; 50DAP, red. For ‘Ailsa Craig’: 27DAP, IG; 39DAP, MG; 41DAP, B-1; 42DAP, B; 43DAP, B + 1; 47DAP, pink; 52DAP, red. Results are represented as the mean of three replications ± SD. Each replication consisted of pooled samples as explained in materials and methods, and was the same used for AsA determination and gene expression analysis.