| Abstract: | Two-year-old rubber-producing shrub, guayule (Parthenium argentatum, cv. 11591), was treated with low temperature (15 °C). The leaves were harvested at regular intervals (0, 2, 4 and 6 days) and the contents of protective antioxidants (ascorbic acid, monodehydroascorbate and caroteniods) and antioxidative enzymes (superoxide dismutase, catalase, peroxidases, glutathione reductase and monodehydroascorbate reductase) were determined. Low temperature-induced significant increase in the contents of ascorbic acid, monodehydroascorbate and caroteniods as well as the activities of all antioxidative enzymes. The results show an increase in several components of the antioxidant system in cold-treated guayule plants, which may suggest a role in mitigating an increase in oxidative stress. |
