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Plant and Soil

, Volume 72, Issue 1, pp 13–29 | Cite as

The acquisition of phosphorus byLupinus albus L.

V. The diffusion of exudates away from roots: a computer simulation
  • W. K. Gardner
  • D. G. Parbery
  • D. A. Barber
  • L. Swinden
Article

Summary

A model predicted that the concentration profile of exudate would be less steep and its concentration values higher for larger diameter roots and that rhizosphere volume/g of root would be maximised at a particular root size for a given exudation rate. Root hairs, if active in secretion, would increase the rhizosphere volume/g of root and the substrate concentrations in it. Proteoid roots would increase the concentration of diffusing substance even further, although the rhizosphere volume per g of root may decline due to overlap effects. These effects are discussed in relation to the rate and extent of reactions between exudates and the soil.

Key words

Exudation Lupins Lupinus albus L. Micro-organisms Proteoid roots Rhizosphere 

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Copyright information

© Martinus Nijhoff/Dr W. Junk Publishers 1983

Authors and Affiliations

  • W. K. Gardner
    • 1
  • D. G. Parbery
    • 1
  • D. A. Barber
    • 1
  • L. Swinden
    • 1
  1. 1.Department of Plant Sciences, School of Agriculture and ForestryUniversity of MelbourneParkvilleAustralia

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