In angiosperms, the flower occur singly or in groups. When a flower arises singly it is called a solitary flower. A group of flowers are variously clustered together is called inflorescence. The inflorescence may be divided into two main groups, they are racemose and cymose.
Racemose inflorescence (Indefinite inflorescence): This inflorescence is also called infinite and indeterminate type. growth of the peduncle is infinite. here the terminal bud will not modify into a flower. Racemose inflorescence is of two types: Simple and Compound.
Cymose Inflorescence (Definite inflorescence): is the name of determinate or definite inflorescence in which the tip of the main axis terminates in a flower and further growth continues by one or more lateral branches which also behave like the main axis. on the basis of arrangement of flowers cymose inflorescence are of different types as monochasial cyme, dichasial cyme and polychasial cyme.
Racemose vs Cymose
1. The growing point seldom ends in a flower.
2. The floral axis or peduncle is monopodial.
3. The formation of flowers is indefinite or unrestricted.
4.The arrangement of flowers is acropetal.
5.The arrangement of flowers in a group is centripetal, that is , the younger flowers are towards the centre and the older towards the outside.
1. The growing point always forms a flower.
2. The floral axis is sympodial or multipodial.
3. The definite or restricted number of flower formed.
4.The actual arrangement of flowers is basipetal which is clearly visible in biparous and multiparous cymes.
5. The arrangement of flowers in a cyme head and other types of groupings is centrifugal, that is, the older flowers are towards the centre and the younger towards the periphery.