The aim of this study was to investigate the effects of low temperature (4 °C), cadmium sulphate (100 μM), or their
combination on content of free proline (Pro), glutathione (GSH), and phytochelatins (PCs) in wheat (Triticum aestivum L.)
leaves. Results revealed an increase in proline and phytochelatins accumulation in leaves of wheat seedlings along with
enhanced cold tolerance at the low temperature, CdSO4, and their combination. Moreover, there were increases in
mRNA content of TaP5CS and TaPCS1 genes, encoding Δ1-pyrroline-5-carboxylate synthase (P5CS) and phytochelatin
synthases (PCS), respectively. A rapid increase in glutathione content was found within 1 h of exposure to the low
temperature and its combination with CdSO4, followed by a drop. However, upregulation of the TaGS1 gene, encoding
glutathione synthetase (GS), was maintained during 7 d. A significant decrease in glutathione content on the seventh
day of exposure to the low temperature, CdSO4, and their combination was most probably due to its involvement in
cadmium detoxification and/or in phytochelatin synthesis. Our data suggest that proline, glutathione, and phytochelatins
may be important for plant tolerance to low temperature and cadmium stress in wheat.