1Chapter 0 Anatomy and Biochemistry of Vanilla Bean Development (Vanilla planifolia G. Jackson)

The fruit of the vanilla plant is commonly known as a “bean” being similar in shape with those of legumes, which stems from the evolution of a single carpel. In fact, from a botanical viewpoint, it is not actually a bean as it results from the evolution of three fused carpels, but a capsule (dry, dehiscent fruit resulting from the evolution of several carpels). In the orchid family, which includes the genus Vanilla, the capsule is composed of three valves that are delimited by six dehiscence splits (two per carpel) situated at either end of the placentas (paraplacental dehiscence, Figure 10.1a) (Dupont and Guignard, 2007).