| 摘要: |
| 为了解濒危植物广西八角莲对环境光强的适应性,该研究以广西八角莲同属渐危种八角莲为对照,采用Li-6400便携式光合测定系统对两种植物的光合光响应特性进行了比较研究,进而探讨广西八角莲的濒危机制。结果表明:广西八角莲与的八角莲的光饱和点分别为440和530 μmol·m-2·s-1,光补偿点为13.25和13.10 μmol·m-2·s-1,最大净光合速率为3.62和6.81 μmol·m-2·s-1,表观量子效率为0.065和0.042 μmol·μmol-1,两种八角莲均具阴生草本植物的光合特性,但其光补偿点与饱和点均高于一般阴生草本,10%～30%阴蔽度的林下生境有利于两种八角莲的生长; 两种植物相比较,广西八角莲的光合能力较弱,光饱和点较低,但其弱光下的量子效率较高。大部分光强下,八角莲的净光合速率、气孔导度和蒸腾速率均高于广西八角莲,但广西八角莲的瞬时水分利用效率却高于八角莲,表明广西八角莲的光合策略比较保守,以较低的光合积累为代价来维持较高的水分利用效率,以保持体内水分平衡。 |
| 关键词: 广西八角莲, 八角莲, 净光合速率, 蒸腾速率, 水分利用效率 |
| DOI：10.11931/guihaia.gxzw201407028 |
| 分类号:Q945.79 |
| 文章编号:1000-3142(2016)05-0570-04 |
| 基金项目:广西科技成果转化资金项目(桂科转1346004-29); 桂林市科技成果转化与应用项目(20140124-2); 桂林市科技攻关项目(20130408)[Supported by Guangxi Fund for Scientific and Technological Achievements Transformation(1346004-29); Guilin Fund for Scientific and Technological Achievements Transformation and Application(20130408); Key Technology R & D Program of Guilin(20130408)]。 |
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| Comparative study on the photosynthetic light response characteristics of Dysosma guangxiensis and D. versipellis |
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TANG Feng1, LIANG Hui-Ling2, WANG Man-Lian2*
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1. Biology Institute, Guangxi Academy of Sciences, Nanning 530007, China;2. Guangxi Institute of Botany,
Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin 541006, China
1. Biology Institute, Guangxi Academy of Sciences, Nanning 530007, China; 2. Guangxi Institute of Botany,
Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin 541006, China
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| Abstract: |
| In order to understand the ecophysiological adaptation mechanisms of the endangered plants Dysosma guangxiensis to light environment, we studied the photosynthetic light response characteristics of D. guangxiensis and the same genera vulnerable species D. versipellis with Li-6400 Portable Photosynthesis(Li-Cor Inc., USA), and then discussed the endangered mechanism of D. guangxiensis. The results showed that the light compensation point of D. guangxiensis and D. versipellis was 440 and 530 μmol·m-2·s-1, the light compensation point was 13.25 and 13.10 μmol·m-2·s-1, the maximum net photosynthetic rate was 3.62 and 6.81 μmol·m-2·s-1, and the apparent quantum yield was 0.065 and 0.042 μmol·μmol-1, respectively. That is to say, the two species are shade herb, but the light compensation point and the saturation point are higher than the general shade herb, and 10%-30% shading forest habitat are conducive to the growth of the two species; compared with D. versipellis, the photosynthetic capacity of D. guangxiensis was weak, the light saturation point was lower, but its quantum efficiency under low light was higher. In comparison, the net photosynthetic rate, transpiration rate and stomatal conductance of D. versipellis were higher than those of D. guangxiensis under most light intensities, but the water use efficiency of D. guangxiensis was higher than that of the former, which indicated that the photosynthetic strategy of D. guangxiensis was more conservative, with lower photosynthetic accumulation as the cost to maintain higher water use efficiency, in order to maintain the water balance in body. |
| Key words: Dysosma guangxiensis, D. versipellis, net photosynthetic rate, transpiration rate, water use efficiency |
