A cymose inflorescence arranged in pairs at the nodes, in the manner of a false whorl, is called a verticillaster (see photograph). In such cases, the arrangement of flowers is Centripetal, i.e., the oldest flowers towards the periphery and the youngest ones towards the Centre.When the lateral axes develop successively on the same side, forming a sort of helix, the cymose inflorescence is known as helicoid or one-sided cyme, e.g., in.a one-sided cyme called a helicoid cyme (see photograph). Verticillaster is a cluster of sessile or subsessile flowers borne on a dichasial cyme ending in monochasial cyme (scorpioid) in the form of condensed whorl on either side of the node.The main axis of a racemose inflorescence is sometimes may be compressed and flattened into a disc, bearing a cluster of flowers on its upper surface. Helicoid cyme In which each flowering branch gives rise to one lateral branch that is coiled snail-like and then expanded. Scorpioid cyme: The main reproductive shoot bear a flower at its.Example is sunflower.
Racemose InflorescenceThe main axis may be elongated, shortened, or flattened into a Therefore the classification of Racemose Inflorescence is based on the Development of the main axis and pedicels of the flowers. There is an arrangement of flowers in them is centrifugal i.e., the young flowers are towards the periphery and the older ones towards the center. The flowers develop in Basipetal Succession, i.e., the terminal flower is the oldest and the lateral ones are younger.When the lateral axes develop successively on the same side, forming a sort of helix, the cymose inflorescence is known as helicoid or one-sided cyme, e.g..In a cymose inflorescence, the flowers usually form Clusters. One, two, or more lateral branches develop below the terminal flowers, each ending in a flower and producing daughter axes. Cymose Inflorescence: In this type of inflorescence, the main axis soon ends Flower.
The pedicels of older flowers are longer than those of younger ones, so that all flowers lie at the same level, as in fibers (candytuft). Corymb: The main axis comparatively short. The pedicels of flowers are of the size, e.g., in Larkspur.
Simple umbel: The main axis above the first flower is so much shortened that the internodes between the successive flowers become suppressed. It is found in monocots only. Fleshy spike enclosed in one or bracts, called Spathe e.g., in banana, palm.
The receptacle is surrounded at the base by overlapping bracts which form an Involucre.The capitulum may be homogamous, if all flowers are of the same kind, as in Sonchus, in which the flowers are ligulate (strap-shaped) and bisexual, or heterogamous, in which the flowers are of two types, as in sunflower, the Disc-Florets, tubular and bisexual, occupying the center of the receptacle and the ray florets, ligulate and pistillate or neuter, present at the periphery of the receptacle.This type of inflorescence is characteristic of the composite. The young flowers are present in the center of the receptacle while the older ones toward the periphery. The florets are crowded on the upper surface of the receptacle and while the inflorescence looks like a single flower. Capitulum: The main axis is reduced to a flat, concave, or convex disc, the Receptacle.The flowers are small and are known as Florets. This inflorescence is the characteristics of Umbelliferon.
Uniparous Cyme: The main axis ends in a flower below which a daughter axis is produced which again ends in a flower. The male flowers are present near the apex while the female flowers occupy the rest of the surface, e.g., Banyan, Pepal.Cymose Inflorescence may be Uniparous, Biparous, or Multiparous. Unisexual flowers develop on the inner surface of the hollow receptacle.
The biparous type usually passes into a uniparous cyme by the suppression of one of the two branches at each subsequent branching. Which of the two daughter axes again ends in a flower and produces two daughter axes which continue branching in the same way. Biparous Cyme: The main axis ends in a flower and produces two daughter axes. It is also called Sympodial Cyme, therefore. In both cases, the basal portions of the successive daughter axes become straightened up, to form a false central axis or Sympodium. Uniparous cyme is of two types:(a) Scorpioid cyme: successive daughter axes develop on right and left alternately, forming a zigzag, as in Freesia.(b) Helicoid Cyme: Successive daughter axes are developed on the same side, either right or left, forming a spiral, e.g., in Begonia and some Solanaceae.
Compound Spike: The main axis of the inflorescence bears small lateral spikes instead of sessile flowers, e.g., in wheat, Barley. Compound Raceme: A compound raceme consists of several simple racemes borne in a racemose fashion on the main axis, as in Delphinium. Various types of compound inflorescences met within angiosperms are: Compound InflorescenceIf the main axis of the inflorescence is branched and the branches bear flowers in the same manner as are present on the main axis, the inflorescence is called a compound Inflorescence. The young flowers are either towards the periphery or scattered among the older flowers, as in Acacia, Albizzia. Multiparous Cyme: The main axis ends in a flower and produces a whorl of three or more daughter axes, each of which continues to branch in the same manner, e.g., in Euphorbia.The flowers are arranged in groups or clusters, each of which is really a scorpioid cyme in which the main axis and the successive daughter axes have been reduced and the flowers are almost sessile.
Inside the involucre, surrounding the stalk. The main axis ends in a reduced female flower which is tricarpellary and syncarpous pistil, borne on a long stalk.The flower is surrounded at its base by an involucre.
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