| 摘要: |
| 为探讨濒危植物丹霞梧桐 Firmiana danxiaensis 对不同光照强度的适应机制，以半年生幼苗为
对象，在不同光照强度（CK、L1、L2、L3，即遮荫度分别为 0%、25%、50% 和 75%）下，比较其生长
和光响应曲线。结果表明：随着遮荫强度的增大，丹霞梧桐苗高、地径的净生长量和总生物量呈先上升
后下降趋势，比叶重呈下降趋势，但比叶面积呈上升趋。其生长量、生物量均以 L1 处理最高，苗高、地
径净生长量和总生物量分别为 28.94 cm、0.99 mm 和 25.16 g · 株 -1。随着光合有效辐射的增大，其净光
合速率增长幅度表现为 CK ＞ L1 ＞ L2 ＞ L3；在全光照条件下，丹霞梧桐具有较高的最大净光合速率
（16.12 mmol · m-2 · s-1）、光饱和点（24.33 μmol · m-2 · s-1）和暗呼吸速率（1.41 μmol · m-2 · s-1）。PCA 分析
结果表明，不同光照强度对丹霞梧桐生长及光合参数呈显著相关性。在光照胁迫处理下，丹霞梧桐通过
提高总生物量、增加比叶面积，降低根冠比和比叶重来提高其生长，以及适应特定的光环境，表明该物
种的生长受光环境因子影响大。 |
| 关键词: 丹霞梧桐 光照强度 光适应 濒危植物 |
| DOI： |
| 投稿时间：2023-06-11修订日期：2023-07-03 |
| 基金项目:东莞市社会科技发展项目“极小种群植物丹霞梧桐迁地保育研究”（立项编号：2019507101550） |
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| Effects of Different Light Intensities on the Growth and Light Adaptation of Endangered Species Firmiana danxiaensis |
| CHEN Zhuokang,moluojian,HUANG Qianlin,CHEN Kuixian,LI Jiongxiang |
| (Dongguan institute of forestry science) |
| Abstract: |
| To explore the photosynthetic adaptation of the endangered species Firmiana danxiaensis to
diff erent light conditions,half-year-old seedlings were planted under diff erent light environments(CK, L1, L2, L3,
shade degrees were 0%, 25%, 50% and 75%, respectively),the growth and light response curves were compared.
The results showed that with the increase of shading intensity, the net growth and total biomass of height and
diameter increased first and then decreased, and the specific leaf weight decreased, but the specific leaf area
increased. The height, diameter and total biomass were 28.94 cm, 0.99 mm and 25.16 g per plant, respectively.
With the increase of photosynthetic eff ective radiation, the growth range of net photosynthetic rate was arranged
CK > L1 > L2 > L3. The higher maximum net photosynthetic rate(16.12 mmol·m-2·s-1), light saturation
point(24.33 μmol·m-2·s-1) and dark respiration rate(1.41 μmol·m-2·s-1). The results of PCA analysis showed that the growth and photosynthetic parameters were significantly correlated with different light intensities. Under
light stress, it could adapt to the special light environment by increasing the total biomass, increasing the specifi c
leaf area, decreasing the root-shoot ratio and the specifi c leaf weight. The results showed that the growth of this
species was greatly infl uenced by light environment factors. |
| Key words: Firmiana danxiaensis light intensities light adaptation endangered species |
