Methods of Phloem Visualization: A Clear Future in Sight?
There have been exciting new results in phloem research in recent years, at least in part made possible by the rapid advancement of microscopic techniques. Several methods for visualizing phloem cells are available. The suitability of each method depends on the organ and species being studied, and on the scientific question being addressed. This review will briefly explain the specific challenges associated with phloem cell visualization. It will then focus on common methods currently being used for studying phloem anatomy, development, and function. Emphasis will be placed on the most recent improvements in imaging techniques which had, or most certainly will have, an impact on phloem research.
Key wordsSieve element Companion cell Whole-mount staining Confocal microscopy Electron microscopy X-ray microtomography Super-resolution microscopy Phloem development
Modified pseudo-Schiff propidium iodide
Serial block face scanning electron microscopy
Scanning electron microscopy
Transmission electron microscopy
High-resolution X-ray microtomography
I am grateful to David Seung for critical reading of the manuscript.
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