Leaf Structural Properties that Influence Internal Light Regime and Photosynthetic Efficiency: Epidermal Lens Cells and Internal Leaf Anatomy

光合作用是植物将太阳能转化为化学能的过程。这个过程支撑着这个星球上的所有生命。深入了解光合作用是如何在叶片中发生的，对于理解陆地植物的太阳能转换是必要的。影响内部光系统和光合作用效率的叶片结构属性：表皮晶状体细胞和叶片内部解剖将研究叶片解剖与整个叶片的光合作用表现是如何相关的。已经选出了具有独特解剖特征的特定本土植物。这项研究的目的是使独特的叶片解剖特征、每种叶型内光合作用机构的专化性和整个叶片的光合作用表现之间存在相关性。将被检查的一个重要的叶片解剖特征是叶片表皮细胞通过透镜机制将光聚集在叶片内部的能力。目前的研究表明，这些电池可以将入射光集中到入射水平的6-20倍。此外，这种表皮晶状体的作用似乎强烈地影响了位于叶片内的叶绿体的采光能力。将使用显微镜、气体交换测量和一种新的光纤微探头技术来完成该项目的目标。由此产生的信息可能被应用于与理解植物生物多样性的生理基础、增加作物产量以及植物如何在光合作用上对二氧化碳浓度增加所调节的全球气候变化做出反应的问题上。

Photosynthesis is the process whereby plants convert solar energy into chemical energy. This process supports all life on this planet. An in depth knowledge of how photosynthesis occurs in leaves is necessary for understanding solar energy conversion by land plants. The project Leaf structural properties that influence internal light regime and photosynthetic efficiency: Epidermal lens cells and internal leaf anatomy will examine how leaf anatomy is related to the photosynthetic performance of the whole leaf. Specific native plants have been selected that have unique anatomical features. The purpose of the proposed research is to make correlations between the unique leaf anatomical features, the specialization of the photosynthetic apparatus within each leaf type, and whole leaf photosynthetic performance. One important leaf anatomical character that will be examined is the ability of the leaf epidermal cells to focus light within the leaf interior via a lens mechanism. Current research has shown that these cells can concentrate light 6-20 times above incident levels. Moreover, this epidermal lens action appears to strongly affect light-harvesting by the chloroplasts located within the leaf. Microscopy, gas exchange measurements and a new fiber optic microprobe technique will be used to accomplish the objectives of this project. The resulting information may be applied to problems that relate to understanding the physiological basis for plant biodiversity, increasing crop yield, and how plants may respond photosynthetically to global climate change mediated by increased carbon dioxide concentrations.