《植物生理学报》 2015, 51(1): 119-126

叶片生长进程中气孔发育对叶温调节的影响

吴冰洁^1,2,3, 刘玉军^1,*, 姜闯道^2,*, 石雷²

¹北京林业大学生物科学与技术学院, 北京100083; ²中国科学院植物研究所北方资源植物重点实验室, 北京100093; ³聊城大学农学院, 山东聊城252059

通信作者：刘玉军；E-mail: jcdao@ibcas.ac.cn, yjliubio@163.com；Tel: 010-62836657; 010-62336012

摘　要：

鉴于气孔发育影响气孔导度和蒸腾速率, 推测气孔发育可能影响叶温调节。为验证这一假设并阐述相关规律, 在控光和控温条件下研究了冬青卫矛和华北紫丁香气孔发育、气孔导度、蒸腾速率及其与叶温的关系。结果表明, 伴随冬青卫矛、华北紫丁香叶片生长气孔逐渐增大, 但气孔密度下降; 在此过程中, 气孔导度和蒸腾速率逐步提高, 而叶片温度降低; 尽管冬青卫矛和华北紫丁香叶片的气孔密度和大小差异很小, 但华北紫丁香近轴侧和远轴侧均有气孔分布, 而冬青卫矛则只有远轴侧分布气孔, 且相同条件下华北紫丁香的气孔导度和蒸腾速率高、叶温低。因此, 气孔发育能够促进气孔导度和蒸腾速率提高, 有助于降低叶温; 近轴侧气孔可能更有利于蒸腾降温。

关键词：气孔发育; 气孔导度; 蒸腾速率; 叶片温度

收稿：2014-12-02   修定：2014-12-18

资助：北京市自然科学基金(6122025)和北京市科委项目(Z1411-00006014036)。 致谢 中国科学院植物研究所分子生理重点实验室徐秀苹老师和董凤琴老师在显微观察过程中给予大力帮助。

Effects of Stomatal Development on Leaf Temperature during Leaf Expansion

WU Bing-Jie^1,2,3, LIU Yu-Jun^1,*, JIANG Chuang-Dao^2,*, SHI Lei²

¹College of Biological Science and Biotechnology, Beijing Forestry University, Beijing 100083, China; ²Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; ³College of Agriculture, Liaocheng University, Liaocheng, Shandong 252059, China

Corresponding author: LIU Yu-Jun; E-mail: jcdao@ibcas.ac.cn, yjliubio@163.com; Tel: 010-62836657; 010-62336012

Abstract:

Considering the crucial influences of stomatal development on stomatal conductance and transpiration, we speculated that stomatal development may affect the regulation of leaf temperature. To test this hypothesis, stomatal development, stomatal conductance, transpiration and the relationship between transpiration and leaf temperature were carefully studied in both Euonymus japonicus and Syringa oblata under controlled light intensity and air temperature. Our results showed that the size of stomata increased gradually with leaf expansion in both E. japonicus and S. oblata, resulting in increased stomatal conductance and associated transpiration up to the time of full leaf expansion. Stomatal development helped to reduce leaf temperature through transpirationally driven leaf cooling. Although the differences in density and size of stomata were small between leaves in E. japonicus and S. oblata, there were large differences in stomatal distribution between the two species. Stomata distributed on both sides of leaves in S. oblata, while there were stomata only on abaxial side of leaves in E. japonicus. Under the same conditions of light intensity and air temperature, the stomatal conductance and transpiration of S. oblata were higher than that of E. japonicus, but the leaf temperature in S. oblata was lower than that in E. japonicus. We proposed that adaxial stomata may mainly contribute to reducing leaf temperature by transpiration cooling.

Key words: stomatal development; stomatal conductance; transpiration; leaf temperature