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. 1985 Jan;77(1):168–174. doi: 10.1104/pp.77.1.168

Studies of Root Function in Zea mays

IV. Effects of Applied Pressure on the Hydraulic Conductivity and Volume Flow through the Excised Root

David M Miller 1
PMCID: PMC1064476  PMID: 16664002

Abstract

The volume flux, Jv, and the osmotic driving force, σ△π, across excised root systems of Zea mays were measued as a function of △P, the hydrostatic pressure difference applied across the root, using the pressure jump method previously described (Miller DM 1980 Can J Bot 58: 351-360). Jv varied from 5.3% to 142% of its value in intact transpiring plants as a result of the application of pressure differences from −2.4 to 2.4 bar. The calculated hydraulic conductivity was 5.9 × 10−4 cubic centimeters per second per bar per gram root and was independent of pressure. A model of root function similar to those appearing in the literature failed to provide quantitative accord with the data. A proposed model, which includes the effect of volume flux on the distribution of solutes in the symplasm, predicts accurately Jv △π, and the xylem solute concentration as a function of △P.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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