Types of Placentation
Placenta is the soft fleshy tissue in the ovary on which the ovules are attached. Placentation is the manner by which the ovules and placentae are arrange in the cavity of ovary.
Kinds of Placenation
Various kinds of placentation in flowering plant are:
MARGINAL PLACENTATION: In marginal placentation the ovary consists of one carpel (monocapous Ovary). The two margins of the carpel are fused together and it is along with a straight line of fusion that the ovules are attached. Example of marginal placentation are found in cassia, pride of Barbados, find flamboyant (the family of fabaceac)
In this type, the ovary consists of two or more carpels. These carpels have their margin fused at the centre of the ovary thus leaving cavities as many as the number of carpels in each cavity, the ovules are attached to the placenta which develops from the central axial Example of plants are tomato, orange canna.
In this type the ovary consist of many carpels but they all have a common cavity, the ovules are attached to the pacetnea which form on the inner wall of the ovary.
In the type, the carpels forming the ovary are fused and their partition walls dissolve so that they now have common cavity. The ovules are attached to the placenta which is centrally placed.