关键词: 沙生植物, 干旱、高温胁迫, 抗逆性

Abstract: The osmoregulation matters were investigated in several desert plants including Agriophyllum squarrosum, Convolvulus chinensis grown on shifting sand dune, Artemisia halondendron grown on semi shifting sand dune, Pennisetum centrasiaticum and Setaria viridis grown on fixed sand dune. Under air drought, high temperature(45℃), the soluble sugar, protein, and proline contents were determined. A. squarrosum, C. chinensis were dead during two stresses, in which soluble sugar content increased by 92.8%, especially proline rose by 10.28 times under 12 h treatment of atmosphere dehydration and high temperature compared to non treatment, while soluble protein decreased. A. halondendron survived the two stresses, in which relatively water content (RWC) and soluble protein declined very little by 11.32%, 15.04% respectively; soluble sugar and proline contents increased by 41.57% and 8.95 times respectively. With the extend in the time of treatment, P. centrasiaticum and S. viridis were alive under stresses companied by increasing in soluble sugar of 89.82% and 89.43%, proline of 2.5 times and 2.53 times as well as protein rising. These provide evidences that accumulating proline in A. halondendron, P. centrasiaticum and S. viridis was an important osmoregulation in protection of proteins and intracell water into bound water, while in A. squarrosum, and C. chinensis was a injury symptom due to disassemblage of protein during stresses.

Key words: Desert plant, Drought and high temperature stresses, Resistance