Chloroplast and outside-chloroplast interference of light inside leaves

Our research explored leaf optical patterns when light falls on the leaf’s inner surface and interacts to chloroplasts pigments or with the outside-chloroplast components (structural apparatus) of leaves. Six species of variegated leaves were used to detect effects of chlorophylls (green leaves), carotenoids (yellow leaves – without chlorophylls) and outside-chloroplasts components (albino leaves – without functional chloroplasts) to deep our understand of behavior of light inside leaf beyond spectral interference of pigments. High absorbance at wavelengths shorter than 530 nm in albino leaves (absence of chloroplasts) in addition to high scattering at longer wavelengths (considering the 400–700 nm range) were detected. Changes in measurements of chlorophyll fluorescence spectroscopy performed simultaneously on both side of leaves and using a high fluorescence in red absorption (R) to low effects on fluorescence in far-red (FR) as a proxy, the ratio of fluorescence (R/FR) were associated to differences in penetrability of different wavelengths. From the leaf optical system point of view, internal reflectance and degenerate chlorophyll quantum state are important physical mechanisms that maximize the absorption of wavelengths of low absorptivity, as in the case of green light.