Use of Leaf Optical Properties in Plant Stress Research
Use of Leaf Optical Properties in Plant Stress Research
复制标题
叶片光学特性在植物逆境研究中的应用
DOI：
10.1021/bk-1984-0257.ch018
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
J. Quisenberry
中科院分区：
文献类型：
--
作者：
H. Gausman;J. Burke;J. Quisenberry
叶片反射率可能成为一种“诊断工具”来检测植物在三个方面的胁迫：叶绿素吸收（0.45- 0.75- µm波段），近红外（0.75- 1.35- µm波段）和红外水吸收（1.35- 2.5- µm波段）光谱区域。胁迫可能会增加或减少叶片总叶绿素浓度：低叶绿素浓度通常会导致0.55 µm处的反射率高于高浓度。此外，胁迫抑制了叶片的扩展。受胁迫的叶子的叶肉保持紧凑，因此具有比具有空隙叶肉的“非胁迫”叶子更低的反射率。非胁迫叶片的近红外光反射率较高是由更多的光散射引起的，当光从水合细胞壁（折射率为1.4）进入空气空间（折射率为1.0）。此外，水吸收1.35- 2.5- µm波段内的红外光能量：含水量高的叶片比含水量低的叶片具有更低的反射率。实践方面进行了审查。
Leaf reflectance may become a "diagnostic tool" to detect plant stress in three areas: chlorophyll absorption (0.45- to 0.75- µm waveband), near-infrared (0.75- to 1.35- µm waveband), and infrared-water absorption (1.35- to 2.5- µm waveband) spectral regions. Stress may either increase or decrease leaf total chlorophyll concentration: low chlorophyll concentrations usually cause a higher reflectance at 0.55- µm than higher concentrations. Furthermore, stress inhibts leaf expansion. A stressed leaf's mesophyll remains compact and consequently has a lower reflectance than a "nonstressed" leaf that has a lacunose mesophyll. The higher near-infrared light reflectance for a nonstressed leaf is caused by more light scattering, when light goes from hydrated cell walls (refractive index of 1.4) into airspaces (refractive index of 1.0). Moreover, water absorbs infrared light energy within the 1.35- to 2.5- µm waveband: leaves with high water content have lower reflectance than do leaves with lower water content. Practical aspects are reviewed.