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Phloem pp 203-211 | Cite as

Measuring Phloem Transport Velocity on a Tissue Level Using a Phloem-Mobile Dye

  • Jessica A. SavageEmail author
  • Maciej A. Zwieniecki
Protocol
Part of the Methods in Molecular Biology book series (MIMB, volume 2014)

Abstract

Here we describe an in vivo dye-tracking method for measuring phloem transport velocity in seedlings, leaves and petioles and potentially other translucent plant tissues. The method requires measurement of the fluorescent signal of a phloem-mobile fluorescent dye using sensitive photo-sensors placed external to the plant. Following dye application, velocity is determined using laser fluorescence bleaching and measuring the time it takes for the bleach front to reach a light sensor. This method can be used to measure phloem transport velocity on intact plants with minimal disturbance and has a potential to be used under a variety of growth conditions and in the field. Because there are large differences among species in their anatomy, this method should be optimized to individual plants and tissue types.

Key words

Transport velocity Carboxyfluorescein diacetate Fluorescence Phloem-mobile dyes Fluorescence bleaching FRAP Carbon allocation 

Notes

Acknowledgments

This work was partially supported by the National Science Foundation Integrative Organismal Systems 1656318 (JAS).

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Biology DepartmentUniversity of MinnesotaDuluthUSA
  2. 2.Department of Plant SciencesUniversity of CaliforniaDavisUSA

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