Comparing the effect of chilling stress on peroxidase activity in Eucalyptus Seedlings

Regarding to the importance of Eucalyptus as a pioneer and fast growing species in forest plantation, this research was performed to test the effects of chilling stress on seedlings of E. saligna, E. camaldulensis and E. rubida. The activities of perixidase enzyme were determined in leaves of the species exposed to chilling stress. Temperature treatments were -20, 5, and 24°C and green house condition was considered as control. The samples enzymes were extracted immediately and peroxidase was quantitatively and qualitatively studied. Quantitative studies were accomplished by spectrophotometry (in 530 NM Wave Length) and qualitative studies were performed by polyacrylamid gel electrophoresis (PAGE). Results showed that chilling stress altered the activity of peroxidase in leaves, compared to the control. Also, the enzyme altered in different manners dependent upon several factors, such as plant species, tolerance, or sensitivity to stress, and duration of stress. All of these results seemed to indicate that peroxidase is an important component in a plant's response to stress and that they played a significant role in counteracting chilling stress.