tiliaceae

 11. Tiliaceae

Distribution: The family comprises 41 genera and 400 species distributed in tropical and

temperate parts of the world common examples like Grewia, Tilia, Muntigera and Berria

grown in tropical parts of India. Corchorus species are commercially grown in North Eastern

part of the country.

Salient feature: Flowers are insect pollinated (entomophilous) and are usually protandrous.

Fruits and seeds are dispersed by animals (zoochory).

Description: Plants are mostly trees or shrubs rarely herbs (Corchorus species); leaves are

stipulate; flower is complete, hypogynous; calyx represented by 5 sepals; corolla is sepaloid;

polyadelphous condition is seen with gynandrophore occurrence; placentation is axile.

Leaves: Leaves are usually alternate, rarely opposite, simple, entire or toothed, stipulate or

exstipulate. Stipules are free and often caducous.

Inflorescence: Often arranged in axillary or terminal cyme rarely axillary as in Elaeocarpus.

Flowers:Flowers are complete bisexual rarely unisexual,actinomorphic (regular) and

hypogynous.

Calyx:Consists of 5 sepals (rarely 3 or 4) free or connate with valvate aestivation and

caducous.

Corolla: Consists of 5 petals or equal the number of sepals, free with imbricate, contorted or

valvate aestivation. Petals are sepaloid in elaeocarpus and absent in chartacalyx.

Androecium: Comprises 10 to numerous stamens inserted on a disc, free or polyadelphous

(slightly connate at the base forming 5-10 bundles). Anthers are dithecous, introrse and

opening by a longitudinal (lateral) slit or apical pore. Often a few stamens are reduced to

staminodes. A gynandrophore is sometimes present.

Gynoecium: Made up of 2 -10 carpels with superior ovary and axile placentation. Number of

locules corresponds to the number of carpels.In Elaeocarpus, ovary becomes unilocular due to

dissolution of septa. Number of ovules per locule varies from one to many. Style is one but

number of stigma is equal to the number of carpels.

Fruit: Capsule or drupe.

Seeds:Albuminous (copious endosperm) with a curved embryo having leafy cotyledons.

Floral formula: Br. Brl

K 5 C 5 A10G(2-10)

9Floral Diagram: Tilia cordata Economic Importance

1. Several forms are known as ornamental plants. The common examples are:Tilia europaea (linden tree of europe), Muntingia calabura, Elaeocarpus ganitrus,Grewia tiliaefolia, G. elastica etc. Most of them are grown for their spreading habits with large foliage and white flowers.

2. The bark of Grewia tiliaefolia is used in dysentery and its wood as antidote to opium poisoning.

3. Roots of G. Villosaare used in diarrhoea and G. sclerophylla in cough. 4. Plant mucilage of Triumfetta rhomboideais used in the treatment of Gonorrhea. 5. A good quality of timber is produced by Tilia europaea, Grewia elastica, G. sclerophylla, Elaeocarpus ganitrus etc.

6. Valuable bast fibres (jute of commerce) are derived from Corchorus capsularis and C. olitorius. These fibres are used for making gunny bags and in linoleum backing.

7. Fruits (berries) of Grewia subinaequalis syn. G. asiatica are eaten with taste and are commonly called phalsa.