Types of inflorescence:

The inflorescence is classified into two main types:

1. Racemose

2. Cymose

 

Racemose inflorescence:

Racemose inflorescence is also known as indefinite inflorescence because its peduncle (axis) shows continued growth for an indefinite period.

This is possible because the peduncle has an active terminal bud.

The inflorescence axis never terminates in a flower, i.e. the apical bud of the peduncle is never converted into a terminal flower.

Flowers are arranged in acropetal succession on the peduncle i.e., older flowers in the inflorescence are lower down on the axis, while the younger ones are nearer the apex.

The order of opening of flowers in a racemose inflorescence is always centripetal, i.e. flowers which are peripheral (or lower) in the inflorescence are older and mature (open) earlier, while the

flowers, which are in the centre (or nearer to the apex of inflorescence axis) are younger and mature later.

 

E.g. Gold mohor, Caesalpinia, etc

Cymose inflorescence:

The cymose inflorescence is also called the definite inflorescence as its peduncle has a limited growth.

This is because the apical bud of the peduncle is converted into a flower.

Below this apical bud one or more lateral branches may develop on the main peduncle.

These branches terminate into flower.

The flowers are thus arranged in basipetal succession on the peduncle, i.e. the first t formed and the oldest flower is terminal in position, while the flowers produced later (younger flowers) are lower down in position on the peduncle.

The order of opening of the flowers is centrifugal.

The central (terminal) flower is the oldest and opens first, while the peripheral flowers are younger and open later, e.g. Jasmine, Clerodendron, etc.