EARLY DEVELOPMENT OF THE BARLEY EMBRYO: FINE STRUCTURE

Publisher Website
Google Scholar
Abstract
The ultrastructure of early stages in embryogenesis in barley was examined. Post‐fertilization shrinkage does not occur. Plasmodesmata were not observed in cell walls of the zygote and outer cell walls of embryos. There is little evidence of cellular specialization in earliest embryonic stages, and planes of cell division tend to be irregular although a pattern of cell disposition characteristic of some grass embryos can be discerned. The embryo appears polarized after 2–3 division cycles, but no evolving of dorsiventrality occurs during this period. A basal supensor cell “anchors” the embryo during early embryogenesis, but by about five division cycles the embryo loses its attachment to the nucellus and is completely surrounded by endosperm. An increase in number of ribosomes and mitochondria takes place during early embryogenesis, and mitochondrial dimensions are reduced. A shift in vacuole distribution occurs.
Funding Information
  • National Science Foundation (GB‐6759)