Question

What is the arrangement of floral leaves in the floral bud?
A: Vernation
B: Prefoliation
C: Aestivation
D: Ptyxis

Answer 1

Hint: It plays an important role in the diagnosis of the flowering taxa and systematic character for delimiting. Within a flower bud before it is opened, the positional arrangement of the parts of the flower. It is also various types seen in different species of flower. It is best seen in a matured flower bud by hand section because after anthesis flowers are covered.

Complete answer:
-Within a flower bud, the positional arrangement of the parts of the flower especially sepal and petals is called aestivation. It is also known as estivation.
-It plays an important role in the taxonomic diagnosis of the flower for example in malvaceae flower buds had valvate sepals and in some species it is missing.
-In a bud, arrangement of the young foliage leaves is called vernation.
-In a vegetative bud, arrangement of the leaves is called as perfoliatum
-The arrangement of the individual leaves in a leaf bud is called ptyxis.

Hence, the correct answer is option (C).

Additional information:
-There are various classification of aestivation. Imbricate, contorted, cochleate, controtriplicate, quincuncial, crumpled, decussate, induplicate, open, reduplicate, valvate.
-A special type of aestivation is also seen in plants like peas called vexillary aestivation. In this a large petal enclose two smaller petals. It is also called as papilionaceous corolla.
-Vernation is also classified into \[4\] types. Circinate, convolute, involute and evolute. It is mostly seen in cabbage species where leaves are folded over one another.
-Ptyxis are also classified into $4$ types. Circinate, erect, reflexed and unflexed.

Note: The positional arrangement of the parts of the flower within the flower bud before it opens is called aestivation. Some examples are that Lilac species have valvate aestivation, phlox has contorted aestivation. The arrangement of young foliage leaves in a bud is called a vernation. The arrangement of the leaves in a vegetative bud is called as perfoliation. The arrangement of the individual leaf in a bud is called ptyxis.