Fern Sorus Thin Section
BV-2A Longpass Emission (Medium Bandwidth Excitation) Blue-Violet Set
Autofluorescence emission intensity from a fern (Holly; Cyrtomium caryotideum) sorus indusium. Endogenous autofluorescence in plant tissues arises from a variety of biomolecules, including lignins, chlorophyll, carotene, and xanthophyll. In the blue-violet region, chlorophyll has an absorption band with a high extinction coefficient and produces a significant amount of fluorescence when excited with wavelengths between 400 and 440 nanometers. Note the presence of autofluorescence emission intensity in the green and red spectral regions, which is strongly reminiscent of a darkfield image.