This was observed in roots of wheat seedlings during 4°C stress at 0, 6, 12, 24, 48, 72 h and recovering 25°C for 24 h (total 96 h). Results were expressed as the mean of three replicates (n = 3, 0.1 g fresh roots from 5–10 seedlings in each replicate). Activities of a. superoxide dismutase (SOD), b. catalase (CAT), c. glutathione peroxidase (GSH-Px) and d. peroxidase (POD) in roots of wheat seedlings were examined using assay kits purchased from Nanjing Jiancheng Bioengineering Institute (Nanjing, China). CC+4°C, treated with 20 µg/mL CC under cold stress; CK+4°C, treated with 0.5% DMSO under cold stress; CK+25°C treated with 0.5% DMSO in growth chamber at 25°C.