Related Experiment Video
Updated: Feb 15, 2026

Processing the Loblolly Pine PtGen2 cDNA Microarray
Published on: March 20, 2009
Imaging and Spectroscopy of Natural Fluorophores in Pine Needles
Lloyd Donaldson1, Nari Williams2
1Biotransformation, Scion, Private Bag 3020, Rotorua 3010, New Zealand. lloyd.donaldson@scionresearch.com.
Abstract:
Many plant tissues fluoresce due to the natural fluorophores present in cell walls or within the cell protoplast or lumen. While lignin and chlorophyll are well-known fluorophores, other components are less well characterized. Confocal fluorescence microscopy of fresh or fixed vibratome-cut sections of radiata pine needles revealed the presence of suberin, lignin, ferulate, and flavonoids associated with cell walls as well as several different extractive components and chlorophyll within tissues. Comparison of needles in different physiological states demonstrated the loss of chlorophyll in both chlorotic and necrotic needles. Necrotic needles showed a dramatic change in the fluorescence of extractives within mesophyll cells from ultraviolet (UV) excited weak blue fluorescence to blue excited strong green fluorescence associated with tissue browning. Comparisons were made among fluorophores in terms of optimal excitation, relative brightness compared to lignin, and the effect of pH of mounting medium. Fluorophores in cell walls and extractives in lumens were associated with blue or green emission, compared to the red emission of chlorophyll. Autofluorescence is, therefore, a useful method for comparing the histology of healthy and diseased needles without the need for multiple staining techniques, potentially aiding visual screening of host resistance and disease progression in needle tissue.
More Related Videos
Related Concept Videos
What is Natural Selection?
Nature and Nurture
Chirality in Nature
The Wave Nature of Light
Natural Selection and Adaptation
Beyond physical adaptations,...
Natural and Artificial Concepts

