| 引用本文: | 潘鑫峰, 邹 蓉, 唐健民, 韦 霄, 江海都, 杨一山.广西青梅幼苗与成年树木光合特性和叶片显微结构的比较研究[J].广西植物,2025,45(1):133-146.[点击复制] |
| PAN Xinfeng, ZOU Rong, TANG Jianmin, WEI Xiao, JIANG Haidu, YANG Yishan.Comparative study on photosynthetic characteristics and leaf microstructure of Vatica guangxiensis seedling and adult tree[J].Guihaia,2025,45(1):133-146.[点击复制] |
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| 摘要: |
| 广西青梅为国家一级保护野生植物和极小种群野生植物。该文利用Li-6400便携式光合测定系统分析仪和真空电子扫描镜对广西青梅幼苗和成年树木光合生理特性与结构特征进行比较分析,探究其不同生长发育阶段叶片的光合能力和叶片结构之间的差异。结果表明:(1)直角双曲线修正模型是广西青梅光响应拟合的最佳模型。(2)成年树木叶片的最大净光合速率(Pn max)、光饱和点(LSP)和暗呼吸速率(Rd)均显著高于幼苗,而光补偿点(LCP)低于幼苗(P<0.05)。(3)幼苗的叶绿素a、叶绿素b、叶绿素(a+b)和类胡萝卜素均显著低于成年树木(P<0.05)。(4)成年树木叶片的气孔器长轴、气孔面积和气孔密度显著高于幼苗; 成年树木叶片的叶面积和比叶重(SLW)显著(P<0.05)大于幼苗,而比叶面积(SLA)小于幼苗。综上认为,广西青梅具有幼苗喜阴而成年树木喜阳的光合特性。幼苗的光适应能力、光能利用率较弱以及成年树木过度遮阴导致幼苗无法进行充分光合以满足生长需求,是幼苗无法成长为大树的重要原因。在广西就地保护中可通过人为的方式,对乔木层林木进行人工“开窗”,提供相对充足的光源,以利于广西青梅幼苗生长发育成大树及种群更新; 在引种栽培中,广西青梅幼苗时期需要适当的遮阴处理,以及移栽至有一定荫蔽度的环境中。 |
| 关键词: 广西青梅, 拟合模型, 光合特性, 叶片显微结构, 叶绿素 |
| DOI：10.11931/guihaia.gxzw202310024 |
| 分类号:Q945 |
| 文章编号:1000-3142(2025)01-0133-14 |
| 基金项目:国家重点研发计划课题(2022YFF1300703); 国家自然科学基金(32160091,32060248); 中国科学院“西部之光”计划(2022); 广西林业科技推广示范项目(2023LYKJ03, [2022] GT23); 广西植物功能物质与资源持续利用重点实验室自主项目(ZRJJ2022-2); “桂科学者”创新团队启动项目(CQI-C-192)。 |
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| Comparative study on photosynthetic characteristics and leaf microstructure of Vatica guangxiensis seedling and adult tree |
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PAN Xinfeng, ZOU Rong*, TANG Jianmin, WEI Xiao, JIANG Haidu, YANG Yishan
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Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin 541006, Guangxi, China
Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin 541006, Guangxi, China
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| Abstract: |
| Vatica guangxiensis is a national first-class protected wild plant and the wild plant of extremely small populations. This paper provides a comparative analysis of the photosynthetic physiological characteristics and structural features of V. guangxiensis seedling and adult tree. The Li-6400 portable photosynthesis measurement system analyzer and vacuum electron scanning microscope were utilized to investigate the differences between the photosynthetic capacity and leaf structure of leaves at different stages of growth and development. The results were as follows:(1)The right-angled hyperbolic modified model was the best model to fit the light response of V. guangxiensis.(2)The maximum net photosynthetic rate(Pn max), light saturation point(LSP)and dark respiration rate(Rd)of adult leaves were significantly higher than those of seedling, while the light compensation point(LCP)of adult tree was lower than that of seedling(P<0.05).(3)Chlorophyll a, chlorophyll b, chlorophyll(a+b)and carotenoids in seedlings were significantly lower than those in adult tree(P<0.05).(4)The stomatal long axis, stomatal area and stomatal density of adult tree were significantly higher than those of seedling; the leaf area and specific leaf weight(SLW)of adult tree were significantly larger than those of seedling(P<0.05), and the specific leaf area(SLA)was smaller than that of seedling. In summary, V. guangxiensis exhibits photosynthetic characteristics of a shade-loving seedling and a sun-loving adult tree. The seedlings have weak light adaptation ability and light energy utilization, and are unable to photosynthesize sufficiently to meet their growth needs due to excessive shading by adult tree. This is a significant reason why seedlings are unable to grow into large trees. Therefore, for in situ conservation of V. guangxiensis, human interference can be used to artificially create ‘windows' in the tree layer to provide sufficient light sources. This is conducive to the growth of V. guangxiensis seedlings into large trees and the renewal of the population. On the other hand, for the introductory cultivation of V. guangxiensis, the seedlings need to be appropriately shaded and transplanted to a certain degree of shade. During the initial cultivation process, it is important to provide appropriate shading for seedlings and transplant them to an environment with a suitable level of shade. |
| Key words: Vatica guangxiensis, fitting model, photosynthetic characteristics, leaf microstructure, chlorophyll |
