Abstract: To explore the mechanism of growth retardation under high temperature in Rauwolfia ( Rauvolfia vericillata), the effects of high temperature on membrane integrity, lipid peroxidation , and antioxidant ascorbic acid were examined by measuring the electric conductivity, membrane lipid peroxide malondialdehyde (MDA), and changes of ascorbic acid in Rauwolfia leaves. The results showed that exposure to high temperature (44℃ and 50℃) resulted in increases in electric conductivity and MDA, and decrease in levels of abscorbic acid. Heat acclimation, pretreatment at 37℃, however, maintains ascorbic acid at higher levels than that without heat acclimation , which may be helpful for Rauwolfia to resist heat stress.

Key words: Rauvolfia vericillata