Calotropis
Encyclopedia
Calotropis is a genus
of flowering plant
s in the dogbane
family, Apocynaceae
. They are commonly known as milkweeds because of the sap
they produce. Calotropis species are considered common weed
s in some parts of the world. The flowers are fragrant and are often used in making floral tassels in some mainland Southeast Asia
n cultures. Fibers of these plants are called madar or mader.
The plant is known as aak in Ayurveda
and was used in cases of cutaneous diseases, intestinal worms, cough, ascites, asthma, bronchitis, dyspepsia, paralysis, swellings, intermittent fevers, anorexia, inflammations and tumors. In large doses, Arka is known to act as a purgative and an emetic.
The milky exudation from the plant is a corrosive poison.
The latex is said to have mercury-like effects on the human body, and is some times referred to as vegetable mercury and is used in place of mercury in aphrodisiacs. It is used variously but sometimes leaves are fried in oil for medicinal purposes.
Calotropis species are usually found in abandoned farmland. Cattle often stay away from the plants because of their unpleasant taste and due to presence of cardiac glycoside
s in their sap.
Root bark has Digitalis like effect on the heart, but was earlier used as a substitute of ipecacuanha.
They are poisonous plants; calotropin, a compound in the latex, is more toxic than strychnine
. Calotropin is similar in structure to two cardiac glycosides which are responsible for the cytotoxicity of Apocynum cannabinum
.
Extracts from the flowers of Calotropis procera have shown strong cytotoxic activity in the patients of colorectal cancer.
They are harmful to the eyes.
C. gigantea grows to a height of 8 to 10 ft (2.4 to 3 m) while C. procera grows to about 3 to 6 ft (0.9144 to 1.8 m). The leaves are sessile and sub-sessile, opposite, ovate, cordate at the base. The flowers are about 1.5 to 2 in (3.8 to 5.1 cm) in size, with umbellate lateral cymes and are colored white to pink and are fragrant in case of C. procera while the flowers of C. gigantea are without any fragrance and are white to purple colored, but in rarer cases are also light green-yellow or white.
The seeds are compressed, broadly ovoid, with a tufted micropylar coma of long silky hair.
Pollination
is done by bees (entomophily
). A very interesting mechanism, for pollination, is found.
The stigma
and androecium
are fused to form a gynostegium. The pollen are enclosed in pollinia
(a coherent mass of pollen grains). The pollinia are attached to an adhesive glandular disc at the stigmatic angle. When a bee land on these, the disc gets attached to their legs and thus the pollinia are pulled out when the bee moves away. When the bee visits another flower, the flower gets pollinated.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of flowering plant
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
s in the dogbane
Apocynum
Apocynum, commonly known as Dogbane and Indian Hemp, is a genus of the plant family of the Apocynaceae with seven species. From the Greek: apo, away; cyno, dog, attributed to its toxicity...
family, Apocynaceae
Apocynaceae
The Apocynaceae or dogbane family is a family of flowering plants that includes trees, shrubs, herbs, and lianas.Many species are tall trees found in tropical rainforests, and most are from the tropics and subtropics, but some grow in tropical dry, xeric environments. There are also perennial herbs...
. They are commonly known as milkweeds because of the sap
Sap
Sap may refer to:* Plant sap, the fluid transported in xylem cells or phloem sieve tube elements of a plant* Sap , a village in the Dunajská Streda District of Slovakia...
they produce. Calotropis species are considered common weed
Weed
A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...
s in some parts of the world. The flowers are fragrant and are often used in making floral tassels in some mainland Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
n cultures. Fibers of these plants are called madar or mader.
The plant is known as aak in Ayurveda
Ayurveda
Ayurveda or ayurvedic medicine is a system of traditional medicine native to India and a form of alternative medicine. In Sanskrit, words , meaning "longevity", and , meaning "knowledge" or "science". The earliest literature on Indian medical practice appeared during the Vedic period in India,...
and was used in cases of cutaneous diseases, intestinal worms, cough, ascites, asthma, bronchitis, dyspepsia, paralysis, swellings, intermittent fevers, anorexia, inflammations and tumors. In large doses, Arka is known to act as a purgative and an emetic.
The milky exudation from the plant is a corrosive poison.
The latex is said to have mercury-like effects on the human body, and is some times referred to as vegetable mercury and is used in place of mercury in aphrodisiacs. It is used variously but sometimes leaves are fried in oil for medicinal purposes.
Calotropis species are usually found in abandoned farmland. Cattle often stay away from the plants because of their unpleasant taste and due to presence of cardiac glycoside
Cardiac glycoside
Cardiac glycosides are drugs used in the treatment of congestive heart failure and cardiac arrhythmia. These glycosides are found as secondary metabolites in several plants, but also in some animals, such as the milkweed butterflies. -Function:...
s in their sap.
Root bark has Digitalis like effect on the heart, but was earlier used as a substitute of ipecacuanha.
They are poisonous plants; calotropin, a compound in the latex, is more toxic than strychnine
Strychnine
Strychnine is a highly toxic , colorless crystalline alkaloid used as a pesticide, particularly for killing small vertebrates such as birds and rodents. Strychnine causes muscular convulsions and eventually death through asphyxia or sheer exhaustion...
. Calotropin is similar in structure to two cardiac glycosides which are responsible for the cytotoxicity of Apocynum cannabinum
Apocynum cannabinum
Apocynum cannabinum is a perennial herbaceous plant that grows throughout much of North America - in the southern half of Canada and throughout the United States. It is a poisonous plant: Apocynum means "poisonous to dogs"...
.
Extracts from the flowers of Calotropis procera have shown strong cytotoxic activity in the patients of colorectal cancer.
They are harmful to the eyes.
Botanical Description
C. gigantea and C. procera are the two most common species in the genus.C. gigantea grows to a height of 8 to 10 ft (2.4 to 3 m) while C. procera grows to about 3 to 6 ft (0.9144 to 1.8 m). The leaves are sessile and sub-sessile, opposite, ovate, cordate at the base. The flowers are about 1.5 to 2 in (3.8 to 5.1 cm) in size, with umbellate lateral cymes and are colored white to pink and are fragrant in case of C. procera while the flowers of C. gigantea are without any fragrance and are white to purple colored, but in rarer cases are also light green-yellow or white.
The seeds are compressed, broadly ovoid, with a tufted micropylar coma of long silky hair.
Pollination
Pollination
Pollination is the process by which pollen is transferred in plants, thereby enabling fertilisation and sexual reproduction. Pollen grains transport the male gametes to where the female gamete are contained within the carpel; in gymnosperms the pollen is directly applied to the ovule itself...
is done by bees (entomophily
Entomophily
Entomophily is a form of pollination whereby pollen is distributed by insects. Several insect are reported to be responsible for the pollination of many plant species, particularly bees, Lepidoptera , wasps, flies, ants and beetles. Some plant species co-evolved with a particular pollinator, such...
). A very interesting mechanism, for pollination, is found.
The stigma
Stigma (botany)
The stigma is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. The stigma receives pollen at pollination and it is on the stigma that the pollen grain germinates. The stigma is adapted to catch and trap pollen with various hairs, flaps, or sculpturings...
and androecium
Stamen
The stamen is the pollen producing reproductive organ of a flower...
are fused to form a gynostegium. The pollen are enclosed in pollinia
Pollinium
Pollinium, or plural pollinia, is a coherent mass of pollen grains in a plant.They are the product of only one anther, but are transferred, during pollination, as a single unit. This is regularly seen in plants such as orchids and many species of milkweeds .Most orchids have waxy pollinia...
(a coherent mass of pollen grains). The pollinia are attached to an adhesive glandular disc at the stigmatic angle. When a bee land on these, the disc gets attached to their legs and thus the pollinia are pulled out when the bee moves away. When the bee visits another flower, the flower gets pollinated.
Cultural Significance
- As mentioned earlier in the article, the plant was described as Aak in AyurvedaAyurvedaAyurveda or ayurvedic medicine is a system of traditional medicine native to India and a form of alternative medicine. In Sanskrit, words , meaning "longevity", and , meaning "knowledge" or "science". The earliest literature on Indian medical practice appeared during the Vedic period in India,...
and finds it's use in many traditional medicine. - The flowers of the plant are offered to the Hindu deity ShivaShivaShiva is a major Hindu deity, and is the destroyer god or transformer among the Trimurti, the Hindu Trinity of the primary aspects of the divine. God Shiva is a yogi who has notice of everything that happens in the world and is the main aspect of life. Yet one with great power lives a life of a...