Family of the week Asclepiadaceae

[satish phadke]

---------- Forwarded message ----------
From: Dr.Satish Phadke <phadke...@gmail.com>
Date: Feb 8, 2008 11:19 PM
Subject: [SATISFIED] Asclepiadaceae
To: phadke...@gmail.com

Asclepiadaceae

(Milkweed family)

This family is very closely related to last week's family Apocyanaceae. There are around 250 species in India.

The familiar examples are :

Mandar(Rui) Calotropis :Western and central India

Milkweed :Weed in most part of India

Tylophora Indica : Bengal and Assam

Vegetative characters : Perennial herbs (e.g.Asclepias) or shrubs (e.g.Calotropis) or woody climbers( e.g.Tylophora,Daemia).

Sometimes plants are succulent (Hoya) or xerophytic with cactus like habitat (Stapelia)

A perennial rootstock is commonly present and sometimes the roots are fleshy or tuberous. Plant contains a milky juice present in long branching laticiferous tubes.

Leaves are opposite decussate or rarely alternate, simple, entire and exstipulate.

Inflorescence is usually dichasial cyme arising in leaf axil or sometimes it is racemose or umbellate as in Asclepias and Calotropis. Flowers are perfect, hermaphrodite, actinomorphic, pentamerous and hypogynous. Calyx has five sepals united below to form a short calyx tube. Corolla is gamopetalous and usually five clefted or lobed but sometimes it is campanulate(e.g.Gymnema) or funnelform (e.g. Cryptostegia).

In Ceropegia the straight or curved corolla tube is swollen at the base. Corolla tube is often with a corona which is often in the form of ring of hairs scales or processes. Stamens are five, epipetalous. Gynoecium is bicarpellary. Ovaries are of two carpels free and so also their styles which are united by their apices and dilate to form a pellate stigma with five lateral stigmatic surfaces.

Fruit is of two follicles which are close together or divergent.

Seeds are flattened and commonly bear a terminal tuft of long silky hairs.

The flowers are perfectly adapted for insect pollination and seed dispersal is by wind.

Examples and economic importance:

Figure 1 Calotropis: Mandar or Rui :used in tanning industry.

Figure2 Milkweed Asclepius curassavica

Figure3 Pergularia daemia

Figure 4Wattakaka volubilis flowers

Figure5 Wattakaka volubilis fruit with seeds bearing hair tufts

Cryptolepis buchnani

Ceropegia

Tylophora indica :roots are used in the treatment of Asthma,bronchitis etc.

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Posted By Dr.Satish Phadke to SATISFIED at 2/08/2008 08:15:00 AM

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Dr. Satish Phadke

[J.M. Garg]

I am attaching a picture of Calotropis Procera (Aak), posted earlier by Gaurav Bhatnagar.

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Dr. Satish Phadke
For my Birds, Butterflies, Trees, Lanscape pictures etc., visit  http://commons.wikimedia.org/wiki/Special:Contributions/J.M.Garg