Write the types of Aestivation and Explain .

Explanation

Aestivation : Arrangement of sepals and petals in the flower bud.
Valvate: Margins of sepals or petals do not overlap but just touch each other.
Eg: Calyx in members of Malvaceae, Calotropis, Annona.
Twisted or Convolute or Contorted: One margin of each petal or sepal overlapping on the other petal
Eg: Petals of chinarose.
Imbricate : Sepals and petals irregularly overlap on each other, one member of the whorl is exterior, one interior and the other interior.
Eg: Cassia, Delonix. There are 3 types.
1. Ascendingly imbricate. 2 Quincuncial. 3. Vexillary.
Quincuncial : It is a type of imbricate aestivation in which two petals are external and two internal and one petal with one margin inernal and the other margin external.
Eg: Guava, calyx of Ipomoea, Catharanthus.
Vexillary : Large posterior petals both margins overlap lateral petals. Lateral petals other margin overlaps anterior petals.
Eg: Pea, bean.