Abstract: The single cell was the first cell of somatic embryoid in Asparagus officinalis L.. Electron microscopic observations revealed that early embryogenic cells and meristematic cells had the same characteristics in cell shape and structure. The embryogenic cell was small in size, with large nucleus, dense cytoplasm, thin wall, lots of small vacuoles, and rich in organelles. At later stage, the polarity of embryogenic cell appeared, i.e. nucleus situated at one end of the cell, while the other end was occupied by a large vacuole. The polar type of the embryc)genic cell was similar to that of a zygote. Light microscopic observations revealed :hat ihe embryoids were sequentially differentiated through 2-cells, 4-cells, 8-cells, multicellular proembryo, globularshaped, pear-shaped, rod-shaped, cotyledonary-differentiated and mature embryo stages. The heart-shaped and torpedo-shaped stages were observed during the early stage of embryogenesis. In addition, a typical embryoids were also found in vitro.

Key words: Asparagus officinalis L., Somatic embryogenesis, Embryogenic cell, Cytohistology