Question: Write a note on Mixed Inflorescence. All three types of flowers are present in this inflorescence.
At the base of the cup, the female flowers develop while towards mouth the male flower develops. In this type of inflorescence, you can see the peduncle modified in narrow cup-like structure. Examples include Salvia, Ocimum, Coleus etc. From the main axil, lateral axil arises, on which flowers you can find the flowers. From the axil of each leaf, inflorescence develops. We can find this type of inflorescence in Labiatae/Lamiaceae family, where the leaves are arranged in opposite manner on the stem. This inflorescence is found in Euphorbiaceae family like Euphorbia, Poinsettia, Pedilanthus. The male flowers, which lie towards the centre, mature earlier than the flowers which are towards the periphery. Small male flowers surround these female flowers. Due to the growth of pedicel, this comes out from the cup-shaped structure. In the central part of the cup-shaped structure, you can find the female flowers. The bracts or the involucre fuse and form a cup-shaped structure on the margin. Now, we will look at some special types of Inflorescence.
Dichasial or biparous cyme: In this type, peduncle ends in a flower and from the basal part of peduncle, two lateral branches arise.Uniparous cyme/Monochasial cyme: The peduncle ends in a flower producing lateral branch at a time It is of two types again: Helicoid cyme and Scorpioid cyme.This arrangement is called as the basipetal succession. Here, the older flowers are present at the upper portion and young buds are arranged towards the base. In this type of inflorescence, the peduncle terminates in a flower. Learn more about the Types and Parts of Flower here in more detail. It becomes broad, flattened concave or convex. Capitulum/Racemose head (Anthodium): Here, the peduncle doesn’t grow.At the base of flowers stalk, there is a whorl of bracts forming the involucre. Umbel: An inflorescence in which the flower stalks are of more or less equal in length, arise from the same point.Corymb: In it, the peduncle is short and all flowers are present at the same level because the lower flower has much long pedicel than the upper one.Examples include Colocasia, Maize, Aroids, Palms etc. The flowers are small, sessile and unisexual. Spadix: In it, the peduncle is thick, long and fleshy.Catkin/Amentum: Here, the peduncle is thin, long and weak.Spike: Here, the peduncle is elongated but flowers are sessile.Raceme: When peduncle or (main axis) is elongated and flowers are pedicellate.It does not terminate in a flower and gives off flowers laterally in an acropetal manner (where old flowers are arranged lower side and young flowers are on the upper side). In this type of inflorescence, the main axis continues to grow. Browse more Topics under Morphology Of Flowering Plants
We will look at the various types and arrangements of flowers now. The flowers are arranged with respect to a fixed floral axis. Inflorescence is the arrangement of flowers on the floral axis.