Morphology of Flowering Plants
- It is the mode of arrangement and distribution of flowers on a specialized branch called peduncle [flattened peduncle → receptacle]
- According to position, inflorescence can be terminal [Eg : poppy], intercalary (Eg : bottle brush) and axillary (Eg : shoe flower)
- In simple inflorescence, peduncle is unbranched, which includes Racemose and cymose type
- Racemose is of 2 types (i) simple racemose and (ii) compound racemose
- In simple racemose, the flowers open in centripetal fashion i.e. inner flowers open last and outer flowers open first.
- Below is the list of its types with examples.
⇒ Typical raceme - Delphinium, Raphanus, Lupinus
⇒ Spike - Amaranthus, Achyranthus
⇒ Spikelet - Wheat, oat, grass
⇒ Catkin - Acalypha, Mulberry, poplar
⇒ Spadix - Monocot plants, Aroids
⇒ Corymb - Candytuft, Caesalpinia
⇒ Umbel - Centella
⇒ Capitulum - Helianthus, Marigold
⇒ Capitate - Acacia, Mimosa
- The peduncle is branched and each branch bears flowers is any one of the racemose in compound type.
- Below is the list of examples of compound racemose
⇒ Spike of spodius - Date palm, Coconut, Maize (Female)
⇒ Raceme of racemes - Yucca, Asparagus, Maize (male)
⇒ Corymb of corymbs - Pyrus cauliflower
⇒ Umbel of umbels - Coriander, Fennel, Carrot
⇒ Spike of spikes - Amaranthus spinosus
⇒ Panicle of spikelets - Rice
- Cymose infloresence is also called as definite (or) determinate type as the growing point of the peduncle is used up in the flower formation. Further growth of flowering axis is continued by one or more lateral branches which also end in flowers.
- Below is the types of cymose with its examples.
⇒ Uniparous / Monochasial cyme - Begonia, Drosera, Tecoma, Heliotropium
⇒ Biparous / Dichasial cyme - Dianthus, silene, Bougainvillea, Jasminum, Teak.
⇒ Multiparous / Polychasial cyme - Calotropis, Hamelia.
⇒ Cymose head - Anthocephalus cadamba
⇒ Scapigerous cyme umbel - Allium cepa.
- In mixed inflorescence, one could observe both the characters of racemose and cymose.
⇒ Thyrsus - vitis vinifera
⇒ Mixed spadix - Banana
⇒ panicle of spikelets - oat, rice
⇒ Corymb of capitula - Ageratum.
- Special inflorescence include modified simple cymose inflorescence formed due to over crowding of flowers.
⇒ Hypanthodium - Ficus (Peepal, Fig, banyan)
⇒ Coenanthium - Dorstenia
⇒ Verticillaster - Ocimum, salvia, Leucas, mint, Lavender
⇒ Cyathium (cup like involvore) - Euphorbia, poinsettia, pedilanthus
View this video for the topic from 43:05 to 55:00
Disclaimer: Compete.etutor.co may from time to time provide links to third party Internet sites under their respective fair use policy and it may from time to time provide materials from such third parties on this website. These third party sites and any third party materials are provided for viewers convenience and for non-commercial educational purpose only. Compete does not operate or control in any respect any information, products or services available on these third party sites. Compete.etutor.co makes no representations whatsoever concerning the content of these sites and the fact that compete.etutor.co has provided a link to such sites is NOT an endorsement, authorization, sponsorship, or affiliation by compete.etutor.co with respect to such sites, its services, the products displayed, its owners, or its providers.