CALCIUM IN POLLEN PISTIL INTERACTION IN PETUNIA-HYBRIDA HORT .1. LOCALIZATION OF CA2+ IONS IN MATURE POLLEN GRAIN USING PYROANTIMONATE AND AUTORADIOGRAPHIC METHODS

The localization of Ca2+ in the mature pollen grain and the now of the se ions from the somatic tissues of the anther to the pollen grains ha s been studied using pyroantimonate and autoradiographic methods. In t he pollen grain, Ca2+ ions have been localized in the sporoderm and in the cytoplasmic vesicles of probably dictyosomal origin. Calcium ions were transported into the sporoderm together with the compounds of de generating tapetum. The material of degenerating tapetum forms pollen coat surrounding the mature pollen grain.