Multilamellar bodies linked to two active plasmalemma regions in the pollen grains of Sarcocapnos pulcherrima

Abstract

The presence of visible multilamellar bodies in the cytoplasm of pollen grains of at least seven species of the family Papaveraceae has led us to study the behaviour of these bodies during pollen-grain ontogeny and in growing pollen tubes of Sarcocapnos pulcherrima C. Morales & R. Garcia germinated in vitro. Our transmission-electron-microscope (TEM) studies in pollen grains show that the multilamellar bodies may be classified as: 1) small, isolated and placed in the region of apertures in the cytoplasm; and 2) large, in clusters and in contact with the active plasmalemma apertures only when tubules are being formed in the apertural intine. Similar types of multilamellar bodies to those observed in the pollen apertures can be seen near the apex of the growing pollen tube (small and isolated) and in contact with the apex plasmalemma (large and clustered). Our results support the hypothesis that the multilamellar bodies are functionally linked to moments when the cytoplasmic membrane is very active. We have also linked the multilamellar bodies to Golgi vesicles as they both react positively to acid-phosphatase (AP) staining and also to the plasmalemma by the thiocarbohydrazide-silver proteinate-staining (TCH-Sp) electron-contrasting technique.

Keywords

• ontogeny
• papaveraceae
• pollen apertures
• pollen tubes
• tem
• ultrastructure