What are the types of Racemose inflorescence?

What are the types of Racemose inflorescence?

Aug 09, 2022, 16:45 IST

Simple racemose inflorescence is of following types.

1. Raceme: Here pedicellate flowers are present on peduncle. E.g Delphinium (Larkspur, Raphanus (Radish), Mustard. For More Biology Doubts check out our biology doubts section.
2. Spike: Here sessile flowers are present on peduncle. e.g Callistemon (Bottle brush), Amaranthus, Achyranthus, Adhatoda.
3. Spadix: Here peduncle is thick and fleshy with upper part sterile and lower part bearing one or both the types of unisexual flowers, surrounded by a large brightly coloured bract called spathe e.g: Colocasia (Arum), Arisaema . In maize, the female flowers develop in a spadix.
4. Catkin (or Amentum): It is pendulous spike which bears female or male flowers but not both. e.g Mluberry.
5. Strobile: It is like spike inflorescence but flowers develop in the axils of persistent membranous bract. e.g Humulus (Hop)

Corymb

• Here main axis is comparatively short.
• Upper flowers have much shorter pedicel than the lower ones, so that all the flowers are brought more or less to the same level. g : Iberis amara (Candytuft)

Corymbose

• Inflorescence appears like corymb near the growing point.
• It appears like raceme lower down.
• Pedicel of the upper flower is shorter as compared to lower flower.
  Ex: Brassica campestris (Mustard)

Umbel

• Here peduncle is shortened
• All flowers have pedicel of equal length.
• All the flowers arise from a single point, like the ribs of an umbrella.
• At the base of pedicel, there is a whorl of bracts forming an invoucre.
  g Allium cepa (Onion), Hydrocotyle asiatica

Capitulum (Head)

• Peduncle is flattened called receptacle.
• A large number of sessile flowers are borne on the receptacle.
• Two kinds of florets can be recognized on receptacle.
• Ray florets

These are female or sterile, zygomorphic, arranged in one or more whorls
on the rim of receptacle

Disc florets: These are bisexual, actinomorphic present at centre.

e.g. Sunflower, Marigold

Students can also access the Zoology Notes & Botany Notes from here.

What are the types of Racemose inflorescence pdf