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.

Spectral indices for the detection of salinity effects in melon plants

“…The Car/Chl-a ratio generally increases in senescing and unhealthy plant conditions (Peñuelas et al, 1995) so salinity tolerance of melon plants may be associated with this response. CRI 550 exhibits a direct linear correlation with carotenoid content (Gitelson et al, 2002), but the carotenoid content values are quite low and could affect the robustness of the relationship. The relationship between Car/Chl-a and SIPI is not linear and SIPI has low sensitivity to the low Car/Chl-a values obtained (Peñuelas et al, 1994).…”

Optimizing spectral indices and chemometric analysis of leaf chemical properties using radiative transfer modeling

“…Quantifications of C xc and LMA are much more challenging, because they are masked by stronger absorbers like C ab in the visible and EWT in the infrared (Gitelson et al, 2002;Kokaly et al, 2009;Zur et al, 2000). The number of methods to retrieve carotenoid content is limited Chappelle et al, 1992;Féret et al, 2008;Gitelson et al, 2002Gitelson et al, , 2006Sims and Gamon, 2002;Zur et al, 2000) and there are even less focusing on anthocyanins Gitelson et al, 2001Gitelson et al, , 2006Gitelson et al, , 2009Sims and Gamon, 2002). LMA gathers several types of constituents, which show strongly overlapping optical properties.…”

Narrow band spectral indexes for chlorophyll determination in soybean canopies [Glycine max (L.) Merril]

“…With the development of hyperspectral remote sensing in the 1980s, the possibility has arisen to quantify each of these pigments individually in extensive agricultural crop areas (Dawson et al, 1998a,b;Fourty and Baret, 1998;Green et al, 1998;Martin et al, 1998;Dawson et al, 1999;Jago et al, 1999, Kokaly andClark, 1999;Gitelson et al, 2002). Such information can be used for the determination of the physiological state of the vegetation (detecting stresses), for species discrimination (monitoring phenological characteristics) and for productivity estimation (measurement and interpretation of absorbed photosynthetically active radiation) (Blackburn, 1998a,b).…”