Sexual Plant Reproduction

, Volume 5, Issue 1, pp 57–63

Effect of electrical fields and external ionic currents on pollen-tube orientation

  • R. Malhó
  • J. A. Feijó
  • M. S. S. Pais
Original Articles

DOI: 10.1007/BF00714558

Cite this article as:
Malhó, R., Feijó, J.A. & Pais, M.S.S. Sexual Plant Reprod (1992) 5: 57. doi:10.1007/BF00714558

Summary

Agapanthus umbelatus pollen tubes (PTs) display a number of different growth patterns when germinated in an electric field of 750 mV· mm−1. When pollen is germinated near the cathode (82.44% of orientation to the cathode side) or near the anode (55.35% of orientation to the anode), growth is oriented parallel to the applied field but when germinated at an intermediate position, there is random growth. An increase and decrease in the orientation rates as well as reversion of the polarized growth were observed when the growth conditions were systematically altered. These findings reflect the influence of different ionic currents present in the germination medium. These ionic currents induce the formation of ionic gradients, which were monitored by ion-HPLC. The individual omission of Ca2+, K+, Mg2+ and Cl suppresses or alters the oriented growth pattern. The presence of ionic gradients is not by itself suficient to trigger the polarization of tube growth as the presence of an electric field which drives the ionic currents is essential for this to occur.

Key words

Agapanthus umbelatusElectric fieldsIonic currentsPolarized growthPollen tube

Abbreviations

PT

Pollen tube

DNS

3,5-dinitro salycilic acid;

TP

transient polarization

HPLC

high precision liquid chroma tography

DC

direct current

Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • R. Malhó
    • 1
  • J. A. Feijó
    • 1
  • M. S. S. Pais
    • 1
  1. 1.Departamento de Biologia VegetalFaculdade de Ciências da Universidade de Lisboa, R. Ernesto de VasconcelosLisboaPortugal