Assessing Carotenoid Content in Plant Leaves with Reflectance Spectroscopy¶

Abstract

Spectral reflectance of maple, chestnut and beech leaves in a wide range of pigment content and composition was investigated to devise a nondestructive technique for total carotenoid (Car) content estimation in higher plant leaves. Reciprocal reflectance in the range 510 to 550 nm was found to be closely related to the total pigment content in leaves. The sensitivity of reciprocal reflectance to Car content was maximal in a spectral range around 510 nm; however, chlorophylls (Chl) also affect reflectance in this spectral range. To remove the Chl effect on the reciprocal reflectance at 510 nm, a reciprocal reflectance at either 550 or 700 nm was used, which was linearly proportional to the Chl content. Indices for nondestructive estimation of Car content in leaves were devised and validated. Reflectances in three spectral bands, 510 ± 5 nm, either 550 ± 15 nm or 700 ± 7.5 nm and the near infrared range above 750 nm are sufficient to estimate total Car content in plant leaves nondestructively with a root mean square error of less than 1.75 nmol/cm2.

Non-destructive estimation of foliar chlorophyll and carotenoid contents: Focus on informative spectral bands

“…Norway maple and horse chestnut leaves were from a park at Moscow State University (Russia), beech leaves were from the University of Karlsruhe campus (Germany). The leaf total Chl and Car content was determined analytically from the same leaf samples used for reflectance measurement (details are in Gitelson et al, 2001Gitelson et al, , 2002Gitelson et al, , 2003. Pigment content was expressed on a leaf area basis.…”

Constructing satellite-derived hyperspectral indices sensitive to canopy structure variables of a Cordilleran Cypress (Austrocedrus chilensis) forest

“…The former band is located within a section of the vegetation spectral curve known as the green edge, i.e. the reflectance increase from the strong absorption of blue region to the reflection peak in the green region (between 480 and 530 nm), which is maximally sensitive to the bulk foliar pigment content (Gitelson et al, 2001(Gitelson et al, , 2002b. NIR wavelengths, by contrast, are well-known for their sensitivity to changes in foliage amount.…”

Genetic variation in leaf pigment, optical and photosynthetic function among diverse phenotypes of Metrosideros polymorpha grown in a common garden

“…To build upon previous work, we determined the genetic variation across source populations in the concentrations of pigments, F PSII and ETR in relation to the variation in SLA and N. We also sought linkages between leaf biochemical and physiological characteristics and their spectral reflectance and absorption properties, the latter being two integrative measures of overall leaf functional status. Previous work has shown that the amount and quality of visible light reflected from leaves is linked to leaf structure, N and pigment concentrations (Gates et al 1965;Curran 1989); indices derived from narrowband reflectance and transmittance are often correlated with foliar concentrations of N and Chl (Markwell et al 1995;Richardson et al 2002;Sims and Gamon 2002;Gitelson et al 2003;le Maire et al 2004), Car (including specific xanthophyll pigments) and anthocynanin, as well as with the light-use efficiency of photosynthetic carbon gain (Gitelson et al 2001(Gitelson et al , 2002Merzlyak et al 2003). Our study thus included leaf reflectance and absorption measurements to evaluate if spectral patterns of light use correlate with leaf biochemical constituents in a way that is indicative of photosynthetic capacity across distinct phenotypes of M. polymorpha.…”