Related Experiment Video
Updated: Jul 26, 2026

Collection and Analysis of Arabidopsis Phloem Exudates Using the EDTA-facilitated Method
Published on: October 23, 2013
Phloem Pressure Differences and C-Assimilate Translocation in Ecballium elaterium
S N Sheikholeslam1, H B Currier
1Department of Botany, University of California, Davis, California 95616.
Abstract:
The role of phloem turgor pressure in (14)C-assimilate translocation in Ecballium elaterium A. Rich was studied. The direction of translocation was manipulated by two methods: darkening, or defoliation, of the upper or lower halves of the shoots. After 24 hours of labeled assimilate movement, sieve tube turgor levels were measured with the phloem needle technique. Distribution of label, determined by autoradiography and counting, revealed a direct correlation between the direction of assimilate transport and the pressure difference. Phloem turgor levels always decreased in the stem of darkened shoots; this resulted in greater pressure differences in the stem between the source leaf receiving (14)CO(2) and treated regions.
Related Concept Videos
Tonicity in Plants
Water and Mineral Acquisition
Short-distance Transport of Resources
Xylem and Transpiration-driven Transport of Resources
Phloem and Sugar Transport
The Apoplast and Symplast

