Planta

, Volume 214, Issue 1, pp 158–162

Changes in stomatal behaviour in the calcicole Leontodon hispidus due to the disruption by ozone of the regulation of apoplastic Ca2+ by trichomes

Authors

  • Lionel D. De Silva
    • Institute of Environmental and Natural Sciences, Department of Biological Sciences, Lancaster University, Lancaster, LA1 4YQ, UK
  • Terry A. Mansfield
    • Institute of Environmental and Natural Sciences, Department of Biological Sciences, Lancaster University, Lancaster, LA1 4YQ, UK
  • Martin R. McAinsh
    • Institute of Environmental and Natural Sciences, Department of Biological Sciences, Lancaster University, Lancaster, LA1 4YQ, UK
Rapid Communication

DOI: 10.1007/s004250100674

Cite this article as:
De Silva, L.D., Mansfield, T.A. & McAinsh, M.R. Planta (2001) 214: 158. doi:10.1007/s004250100674

Abstract.

Regulation of the concentration of Ca2+ in the apoplast of plants is essential in order to allow Ca2+-dependent processes, such as Ca2+-mediated signal transduction in stomatal guard cells, to function correctly. This is particularly important for plants growing with high levels of Ca2+ in the rhizosphere. Recently, we have shown that in two calcicoles, Leontodon hispidus L. and Centaurea scabiosa L., trichomes play a key role in this regulatory process. Ozone is known to have a marked effect on plant Ca2+ homeostasis. Therefore, we have examined the effect of this pollutant on the regulation by trichomes of apoplastic Ca2+ in the calcicole L. hispidus. Treatment with 100 nl l–1 ozone resulted in a reduction in stomatal conductance of approximately 25% in plants grown with 15 mM Ca2+ in the rhizosphere. Analysis of total Ca2+ levels revealed that these changes in stomatal behaviour reflect a decrease in the ability of trichomes to sequester Ca2+. The amount of Ca2+ present in the trichome tip cell was reduced by approximately 38%. This was accompanied by an increase in the levels of Ca2+ in the guard cells and other tissues of the leaf. These data suggest that ozone has a detrimental effect on the ability of trichomes to regulate the concentration of apoplastic Ca2+ in L. hispidus, resulting in altered stomatal behaviour, and hence gaseous exchange, possibly due to the disruption of guard-cell Ca2+-mediated signal transduction. This has important implications for the growth and survival of plants growing in Ca2+-rich soils.

Apoplastic Ca2+ Calcicole Leontodon (calcicole) Ozone Stomate Trichome

Copyright information

© Springer-Verlag 2001