| 摘要: |
| 枫香(Liquidambar formosana)因其叶片入秋后逐渐变红而极具观赏价值,是优良的景观生态树种。为了解枫香叶片结构变化与叶色的关系,该文通过连续监测枫香叶片变红过程中组织结构、光合特性及色素含量的变化,分析叶片结构与其光合特性和色素的关系。结果表明:(1)叶片变色过程中,表皮细胞均为椭圆形,紧密排列,未观察到明显的细胞变异,表面未附着绒毛和蜡质,且上表皮细胞与栅栏组织细胞间排列紧密,未出现较大的气室。(2)随着叶片逐渐变红,叶片结构变化显著,其中叶片、上表皮、栅栏组织和海绵组织厚度及气孔开度均逐渐减小,而气孔器长和宽、单个气孔器面积则逐渐增大。(3)随着叶片结构的变化,其叶绿素含量逐渐减少,致使净光合速率逐渐减小,在出现光破坏时,叶片通过在栅栏组织细胞液泡内合成花色苷来自我保护,而大量的花色苷致使叶片表面呈现红色。综上认为,叶绿素含量降低,花色素苷大量积累是导致枫香叶片变红的直接原因,而枫香叶色变红则是其一系列生理结构特征综合作用的结果。 |
| 关键词: 枫香, 叶片变红, 栅栏组织, 海绵组织, 气孔器, 光合速率, 叶绿素, 花色苷 |
| DOI：10.11931/guihaia.gxzw202012046 |
| 分类号:Q945, Q246 |
| 文章编号:1000-3142(2022)07-1213-09 |
| Fund project:广西壮族自治区林业科学研究院基本科研业务费项目(林科201809号); 广西重点研发计划项目(桂科AB16380100); 广西优良用材林资源培育重点实验室自主课题(2019-A-03-02)[Supported by Fundamental Research Fund for Guangxi Zhuang Autonomous Region Forestry Research Institute(Linke 201809); Guangxi Key Research and Development Plan(AB16380100); Independent Research Fund of the Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation(2019-A-03-02)]。 |
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| Changes of tissue structures, photosynthetic characteristics and pigment contents of Liquidambar formosana leaves in the process of turning red |
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YIN Guoping1, LIU Xiongsheng1, JIANG Yi1*, WANG Yong1,YANG Jisheng2,
XIAO Yufei1, HUANG Ronglin1, JIANG Ying1
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1. Guangxi Key Laboratory of Superior Trees Resource Cultivation, Guangxi Zhuang Autonomous Region Forestry
Research Institute, Nanning 530002, China;2. Guangxi University, Nanning 530004, China
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| Abstract: |
| Liquidambar formosana is an excellent landscape ecological tree species because its leaves turn red gradually after autumn, which is of great ornamental value. In this paper, the changes of tissue structures, photosynthetic characteristics and pigment contents of L. formosana leaves were continuously monitored, and the relationships between leaf structures and photosynthetic characteristics and pigment were analyzed in order to understand the relationships between leaf structure changes and leaf color. The results were as follows:(1)During the discoloration process of L. formosana leaves, the epidermal cells were oval and closely arranged, no obvious cell variation was observed, no villi and wax were attached to the surface, and the upper epidermal cells were closely arranged with palisade tissue cells, there was no large air chamber.(2)With the leaf turning red gradually, the leaf structure changed significantly. The thickness of leaf, upper epidermis, palisade tissue, spongy tissue and stomatal aperture decreased gradually, whereas the length and width of stomatal apparatus and the area of single stomatal apparatus gradually increased.(3)With the change of leaf structure, the chlorophyll content decreased gradually, resulting in the decrease of net photosynthetic rate. When light damage occurred, leaves protected themselves by synthesizing anthocyanins in the vacuoles of palisade tissue cells, then a large amount of anthocyanins caused the leaf surface to show red. Therefore, the decrease of chlorophyll content and the accumulation of anthocyanins were the direct reasons for the redness of L. formosana leaves. To sum up, the red color of L. formosana leaves is the combination result of a series of physiological structure characteristics. |
| Key words: Liquidambar formosana, leaf turn red, palisade tissue, spongy tissue, stomatal apparatus, photosynthesis rate, chlorophyll, anthocyanins |
