Question

What is racemose inflorescence? Give its types.

Answer 1

Hint: A cluster of flowers is called inflorescence. For example racemose, cymose inflorescence. Racemose inflorescence is also known as indefinite inflorescence.

Complete answer:
Racemose inflorescence is an indeterminate type where the flowers mature from bottom to top. In this type of inflorescence, the central axis continues to grow and the flowers at the bottom mature earlier than those on the top (acropetal order). Its main stem continues to grow indefinitely so it is also known as indefinite inflorescence. It is divided into several types based on the central axis and main axis.

>Raceme- In this type the central axis is longer and the flower grows on a short stalk. Eg Mustard.
>Panicle- In this type, the inflorescence has many branches and each branch shows raceme inflorescence. Eg. Oat.
>Corymb- In this type the central axis is short. The pedicles of outermost flowers are longer than the inner flowers.
>Spike- These are similar to raceme but the flowers bloom out directly from the stem. Eg Chaff flowers.
>Spikelet- It consists of many spikes.
>Catkin- These are elongated flowers and have spiral or whorled arrangement. Eg. Willow
>Spadix- It shows a cylindrical shaped arrangement. It can easily attract insects for pollination.
>Umbel- It gives the plant an umbrella-like look. Flowers are arranged in the same length.
>Capitulum – They have short main stems. It has two florets: ray floret and disc floret. Eg. Dahlia.
>Capitate- These have tightly clustered sessile flowers growing on a compressed stalk. Eg. Mimosa

Note: In racemose inflorescence, the central axis continues to grow indefinitely. The flowers at the bottom mature earlier than those on the top. Few examples of racemose inflorescence are barley, wheat.