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  • Short Communication
  • Open Access

The effect of auxins (IAA and 4-Cl-IAA) on the redox activity and medium pH of Zea mays L. root segments

Cellular & Molecular Biology LettersAn International Journal11:31

  • Received: 27 April 2006
  • Accepted: 26 May 2006


Indole-3-acetic acid (IAA) and 4-chloroindole-3-acetic acid (4-Cl-IAA) were tested at different concentrations and times for their capacity to change the redox activity and medium pH of maize root segments. The dose-response surfaces (dose-response curves as a function of time) plotted for redox activity and changes in medium pH (expressed as ΔpH) had a similar shape for both auxins, but differed significantly at the optimal concentrations. With 4-Cl-IAA, the maximal values of redox activity and medium pH changes were observed at 10−10 M, which was a 100-fold lower concentration than with IAA. Correlations were observed between redox activity and medium pH changes at the optimal concentrations of both IAA and 4-Cl-IAA. The results are discussed herein, taking into account both the concentration of the auxins and the effects produced by them.

Key words

  • Redox activity
  • Medium pH changes
  • Root segments
  • Zea mays L
  • Auxins
  • Dose-response surface