The development of the placenta in the anthocerote Phaeoceros laevis (L.) Prosk

The development of the placenta in the anthocerote Phaeoceros laevis (L.) Prosk. was studied by transmission electron microscopy. By the time the sporophyte emerges from the involucre, a conspicuous placental region is formed by the intrusive growth of sporophyte foot haustorial cells into the adjac...

Full description

Saved in:
Bibliographic Details
Published in:Planta 1987-12, Vol.172 (4), p.439-447
Main Authors: Gambardella, Raffaele, Ligrone, Roberto
Format: Article
Language:English
Subjects:
Biological and medical sciences
Cell growth
Cell walls
Crystals
Epidermal cells
Fundamental and applied biological sciences. Psychology
Gametophytes
Labyrinths
Placenta
Plant cells
Plant growth. Development of the storage organs
Plant physiology and development
Sporophytes
Vacuoles
Vegetative apparatus, growth and morphogenesis. Senescence
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The development of the placenta in the anthocerote Phaeoceros laevis (L.) Prosk. was studied by transmission electron microscopy. By the time the sporophyte emerges from the involucre, a conspicuous placental region is formed by the intrusive growth of sporophyte foot haustorial cells into the adjacent gametophyte vaginula tissue. The separation of gametophyte cells by haustorial cells and their incorporation into the placenta are preceded by the loosening and swelling of their walls and the formation of a periplasmic space. This process causes the disruption of the plasmodesmata, and may eventually result in the complete isolation and consequent degeneration of the cells. Crystals are commonly observed in the vacuoles of gametophyte placental cells. Crystals become more abundant during cytoplasmic degeneration, and are released in the placental lacunae that result from the complete dissolution of gametophyte cells. During the subsequent phase of capsule elongation, the gametophyte placental cells that retain the symplastic connection with the adjoining gametophyte parenchyma develop a wall labyrinth typical of transfer cells. Obliteration of the wall labyrinth by deposition of lightly staining wall material is observed later in sporophyte development, in concomitance with capsule dehiscence. Crystals are negative to the periodic acid/thiocarbohydrazide/silver proteinate test for carbohydrates whilst they are completely digested by pepsin or protease, denoting protein composition.
ISSN:0032-0935
1432-2048
DOI:10.1007/BF00393859