Question

Etaerio of follicles occur in–
A. Lotus
B. Rose
C. Calotropis
D. Clematis

Answer 1

Hint: An etaerio or aggregate fruit is a fruit that develops from the merger of several ovaries that were separated in a single flower, in contrast to a simple fruit where fruit develops from one ovary.

Complete Answer:
Let us analyze the options to find the correct answer.
Option A: In lotus (Nelumbium), the fruit is an aggregate and each fruitlet is an achene; and achenes are hairy. The thalamus becomes spongy and some achenes are embedded in it. Therefore, the fruit of lotus is etaerio of achenes and thus this is an incorrect option.

Option B: In rose (Rosa) too, the fruit is an aggregate and each fruitlet is an achene; and achenes are hairy. Here many achenes are present on the saucer-shaped thalamus. Therefore, the fruit of the rose is etaerio of achenes and thus this is an incorrect option.

Option C: In Calotropis the fruit is an aggregate of dehiscent follicle type of fruits. Here two fruitlets (follicles) develop from one flower. Therefore, the fruit of Calotropis is etaerio of follicles and thus this is the correct option.

Option D: In Clematis, the fruit is Achenial which is simple, indehiscent, single-seeded having a thin, dry, woody, or leathery pericarp. Here the pericarp of the fruit is free from the testa of the seed. The seed is attached to the pericarp only at one point. Simple achenes occur in the form of aggregate fruits in Clematis. Therefore, this is an incorrect option.

Thus, the correct option is C. Calotropis.

Note: Flowers with polycarpellary and apocarpous gynoecium give rise to a number of fruitlets as there are a number of free ovaries, each giving rise to one fruitlet. Sometimes, these fruitlets coalesce together and appear as single fruit, but there may be cases wherein the fruitkets remain from one another and thereby forming an etaerio of fruitlets.