关键词: 差不嘎蒿, 冷蒿, 高温胁迫, 生理变化

Abstract: The physiological adaptability mechanism of Artemisia halodendron and A. frigida under high temperature stress in sandy environment was discussed in this paper. The changes of water content in leaves (RWC), permeability, activity of superoxide Dismutase (SOD) and Peroxidase (POD), and content of dissoluble protein and malonaldehyde (MDA) in Artemisia halodendron and A. frigida had been measured by increasing temperature from 30℃ to 60℃. The results showed: ① Although both plants' RWC decreased, A. frigida's leaves resisted water loss better than A. halodendron. ② A. frigida had stronger heat endurance and less membrane damage viewed from change tendency of two plants' membrane permeability, content of MDA and dissoluble protein, and activity of SOD and POD. ③ The main cause of high temperature damage to the two plants was membrane damage due to free radical injury. SOD and POD of A. halodendron had poor thermal stability, so they lost activity at high temperature to clear free radical, which induced high membrane damage. However, SOD and POD's excellent stability of A. frigida had a significant influence on membrane stability.

Key words: Artemisia halodendron, A. frigida, High temperature stress, Physiological change