Plant Ecophysiology Laboratory, Department of Biology, Brazil; Biochemistry of Plants Laboratory, Department of Biochemistry, Brazil; State University of Maringá, Av. Colombo, 5790, Jd. Universitário, 87020-900, Maringá, Paraná, Brazil.
Plant Ecophysiology Laboratory, Department of Biology, Brazil; State University of Maringá, Av. Colombo, 5790, Jd. Universitário, 87020-900, Maringá, Paraná, Brazil.
J Plant Physiol. 2020 Jun;249:153161. doi: 10.1016/j.jplph.2020.153161. Epub 2020 Apr 18.
Optical leaf profiles depend on foliar pigment type and content, as well as anatomical aspects and cellular ultrastructure, whose effects are shown in several species. Monocotyledon and Dicotyledon plants presenting natural pigment content variations and anatomical alterations were analyzed. Each plant species displays its own spectral signatures, which are, in turn, influenced by foliar pigment class (composition) and concentration, as well as anatomical and ultrastructural plant cell characteristics. Plants with no anthocyanin displayed increased reflectance and transmittance in the green spectral region (501-565 nm), while values decreased in the presence of anthocyanin. At wavelengths below 500 nm (350-500 nm), strong overlapping signatures of phenolics, carotenoids, chlorophylls, flavonoids and anthocyanins were observed. Using a partial least squares regression applied to 350-700 nm spectral data allowed for accurate estimations of different foliar pigment levels. In addition, a PCA and discriminant analysis were able to efficiently discriminate different species displaying spectra overlapping. The use of absorbance spectra only was able to discriminate species with 100 % confidence. Finally, a discussion on how different wavelengths are absorbed and on anatomical interference of light interaction in leaf profiles is presented.
叶片光学轮廓取决于叶内色素的类型和含量，以及解剖结构和细胞超微结构，这些因素在多种植物中都有体现。本研究分析了具有天然色素含量变化和解剖结构改变的单子叶和双子叶植物。每种植物都有其自身的光谱特征，而这些特征又受到叶内色素类别（组成）和浓度以及植物细胞解剖和超微结构的影响。不含花青素的植物在绿光区（501-565nm）的反射率和透射率增加，而在存在花青素的情况下则降低。在波长低于 500nm（350-500nm）时，观察到类黄酮、类胡萝卜素、叶绿素、类黄酮和花青素的强重叠特征。将偏最小二乘回归应用于 350-700nm 光谱数据，可准确估计不同叶内色素水平。此外，PCA 和判别分析能够有效地鉴别具有重叠光谱的不同物种。仅使用吸收光谱能够以 100%的置信度鉴别物种。最后，讨论了不同波长的吸收以及叶片轮廓中光相互作用的解剖干扰。
