Phloem pp 125-133 | Cite as

Studying Phloem Loading with EDTA-Facilitated Phloem Exudate Collection and Analysis

  • Qiyu Xu
  • Yunjuan Ren
  • Johannes LiescheEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 2014)


Sugars that are produced by photosynthesis in the leaves are transported in the phloem to heterotrophic sink tissues like roots, fruit, or flowers. Since sugars inside the highly specialized cells of the phloem move by bulk flow, it is the loading and unloading of sugars that determines the rates of allocation between organs. Here, a method is described for the relative quantification of sugars that are loaded into the phloem in leaves. It is based on EDTA-facilitated phloem exudate collection and, therefore, requires control experiments to exclude measurement artifacts. It can be applied to a wide range of plant species, including dicots, monocots, and trees.

Key words

Phloem Phloem loading EDTA-facilitated exudation Carbohydrate allocation Sucrose transport 


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

Authors and Affiliations

  1. 1.College of Life SciencesNorthwest A&F UniversityYanglingChina

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