Login

explain different types of aestivation

Dear student,
Please find below the answer:

Aestivation is defined as a mode of arrangement of petals or sepals in a flower bud.
The different types of aestivation are:-
  • Valvate:-When the petals of a whorl lie close to each other. Example-mustard
  • Twisted:- When one margin of a petal covers the margin of the adjacent petal and its other margin is covered by the margin of the adjacent petal. The arrangement is either in a clockwise direction or in an anti-clockwise direction. Example- china rose
  • Imbricate:- When both the margins of a petal in a whorl is exterior, both the margins of another petal are interior and in the remaining petals one margin is overlapping and the other margin is overlapped. Example- Cassia
  • Quincuncial:- In the whorl of five petals, two are external, two are internal and one margin of the fifth petal is external and its other margin is internal. Example- Ranunculus
  • Vexillary:- In a whorl of five petals, the one posterior petal is largest which covers two lateral petals and in turn thee two lateral petals covers the two anterior or smallest petals. Example- Gram
                                 

Hope this information clears your doubt.
Regards.
 

  • 0
View Full Answer
Dear student,

The mode of arrangement of sepals or petals in floral bud with respect to the other members of the same whorl is known as aestivation. The main types of aestivation are valvate, twisted, imbricate and vexillary.

- Valvate: When the petals of a whorl lie close to each other. Example: mustard

- Imbricate: When both the margins of a petal in a whorl is exterior, both the margins of another petal is interior and in the remaining petals one margin is overlapping and the other margin is overlapped. Example: Cassia

- Twisted aestivation: The cotton has twisted aestivation. Here one margin of appendage overlaps that the next one and so on.

- Vexillary aestivation: In a whorl of five petals, the one posterior petal is largest which covers two lateral petal and in turn these two lateral petals cover the two anterior or smallest petals. Example: peas.

  • 1
What are you looking for?