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研究报告目录 |
Photosynthesis and Metabolite LevelsIn Dehydrating Leaves Of Reaumuria Soongorica |
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| 出 版 社：ACTA BIOLOGICA CRACOVIENSIA Series Botanica |
| 发表时间：2008, 50: 19-26 |
| 台 站：
沙坡头沙漠试验研究站
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| 作 者：刘玉冰 |
| 点 击 率：3621 |
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| 关 键 字：Gas exchange, chlorophyll fluorescence, ribulose-1,5-bisphosphate carboxylase, phosphoenolpyruvate |
| 摘 要：Reaumuria soongorica (Pall.) Maxim., a perennial semishrub, is able to survive almost complete tissue dehydration
when water is withheld from it, and then the stem can rehydrate on rewatering. In this work, a series of
experiments were conducted to characterize the drought-induced changes in two-year-old Reaumuria soongorica.
The plants were subjected to dehydration by withholding water for 15 days. Net photosynthetic rate (Pn),
maximal photochemical efficiency of photosystem (Fv/Fm) and the activity of ribulose-1,5-bisphosphate carboxylase
(RuBPCO) were significantly decreased under drought stress, but phosphoenolpyruvate carboxylase
(PEPCase) activity increased in the leaf extracts. Content of chlorophylls and carotenoids had no marked variation.
Zeaxanthin, the xanthophyll cycle pigment, increased during drying. Plants exposed to drought showed
accumulation of sucrose, with lower soluble protein content than in the control plants. The SDS-PAGE protein
profile showed a 52 kD polypeptide disappearing under progressive drought stress, but no drought-induced protein
occurred. All these findings indicate that the metabolic network systems of Reaumuria soongorica have a
robust regulation capability for management of severe drought stress. |
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