Figure 3. Histological dissection of the somatic embryo at different developmental stages in Coffea canephora.

A) Transverse cut of the early globular stage from the proembryogenic mass at 14 dai. B) Transverse cut of the globular stage. The red arrowhead indicates the cellular organization and the presence of a well-defined procambium. C) Longitudinal cut of the heart stage. The red arrowhead indicates the initiation of the elongation of the procambium zone and the beginning of the cotyledonary primordium is indicated with white stars. D) Longitudinal cut of the torpedo stage. The red arrowhead indicates the elongation of the procambium zone. E) Longitudinal cut of the early cotyledonay stage. The red arrowhead indicates the procambium zone, while the white arrowhead indicates the development of the early cotyledonary primordium. F) Longitudinal cut of the late cotyledonary stage. The red arrowheads indicate the procambium zone, and the white arrowhead indicates the development of cotyledonary primordium. Bars = 200 µm.