Write the types of Aestivation and Explain .

Explanation

Aestivation : Arrangment 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 rest of the three having one margin exterior 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 internal and the other margin external.
Eg: Guava, calyx of Ipomoea, Catharanthus.
Vexillary : Large posterior petals both margins overlap lateral petals. Lateral opetals other margin overlaps anterior petals.
Eg: Pea , bean.