Question

How to write floral formula? Explain.

Answer 1

A floral formula consists of five symbols indicating from left to right:
1) Floral Symmetry
2) Number of Sepals(calyx)
3) Number of Petals(corolla)
4) Number of Stamens
5) Number of Carpels
Floral formula symbol 1: The first symbol in a floral formula describes the symmetry of a flower.
a) (*) Radial symmetry - Divisible into equal halves by two or more planes of symmetry.
b) (x) Bilateral symmetry - Divisible into equal halves by only one plane of symmetry.
c) ($) Asymmetrical - Flower lacking a plane of symmetry, neither radial or bilateral.

Floral formula symbol 2: number of sepals, with “K” representing “calyx”.

Floral formula symbol 3: number of petals, with “C” representing “corolla”. Thus, C5 means a corolla of 5 petals.

Floral formula symbol 4: number of stamens, with “A” representing “androecium”. A $\infty$ (the symbol for infinity) indicates numerous stamens and is used when stamens number more than twelve in a flower. A10 would indicate 10 stamens.

Floral formula symbol 5: number of carpels, with “G” representing “gynoecium”. Thus, G10 would describe a gynoecium of ten carpels.
Other symbols: "P"-Perianth; "B" or "Bt"-Bract or Bracteoles; "V"or "O"-Ovule
$K_{3+3}$ - a calyx with six free sepals, arranged as two separate whorls
$A\infty$ - many stamens
$P3-12$ - perianth from three to twelve tepals.
$A{5}^2-5$ - groups of 2 stamens
$A\left(5\right)$ - five fused stamens
$\left[C\right(5\left)A5\right]$ - corolla fused from 5 petals, fused to stamens
G - Ovary superior; G-Ovary inferior

$K5\left[C\right(5\left)A5\right]G\left(5\right)$
Floral formula of Anagallis arvensis.
Polysymmetric flower.The perianth consists of 5 free sepals and 5 joined petals, which are fused with androecium. Flower is bisexual, it contains 5 stamens, pistil is fused of five carpels, ovary is superior.