Protoplasma

, Volume 208, Issue 1–4, pp 149–155 | Cite as

Changes of calcium distribution in ovules ofTorenia fournieri during pollination and fertilization

  • Z. Kristóf
  • O. Tímár
  • K. Imre
Article

Summary

Calcium distribution in ovules ofTorenia fournieri was studied by electron energy loss spectroscopy and transmission electron microscopic visualization of calcium antimonate precipitates. High calcium levels were found in the ovules ofT. fournieri. Calcium is situated mainly in extracellular regions before fertilization, including the surface of embryo sac, in the mucilage, and among the cells of the egg apparatus. Intracellular calcium was found only in the nucellar cells around the embryo sac and in the epidermis of the central axis and funiculus. After pollination, a labyrinthine structure (coralloid-like cell wall formation) develops on the micropylar surfaces of the egg apparatus that contain high levels of calcium. Calcium levels increase in the degenerating synergid after the penetration of the pollen tube. Calcium-antimonate precipitates are abundant in vacuoles of the disrupted synergid and pollen tube cytoplasm.

Keywords

Calcium Electron energy loss spectroscopy Embryo sac Torenia fournieri Fertilization 

Abbreviations

EELS

electron energy loss spectroscopy

EDX

energy-dispersive X-ray microanalysis

LS

labyrinthine structure

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Copyright information

© Springer-Verlag 1999

Authors and Affiliations

  • Z. Kristóf
    • 1
  • O. Tímár
    • 1
  • K. Imre
    • 1
  1. 1.Department of Plant AnatomyEötvös L. UniversityBudapestHungary

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