The below mentioned article provides an overview on Family – Ranunculaceae. After reading this article you will learn about: 1. Explanation on Family – Ranunculaceae 2. Economic Importance of Family – Ranunculaceae.
Explanation on Family – Ranunculaceae:
There are about 35 genera and 1500 species in this family.
Distribution:
They are chiefly found in the temperate and other colder parts of the world. In our country, the plants are chiefly found in the hilly regions. The species of Clematis are found in the Western Himalayas up to 5,000 feet. Thalictrum javanicum is found to be distributed from Shimla to Sikkim hills and also in Khasia hills of Assam.
Thalictrum foliolosum grows in the Himalayas upto 9000 feet. The species of Ranunculus are found in the Indian plains. In Britain the family is represented by several genera, such as, Ranunculus, Clematis, Anemone, Thalictrum, Paeonia, Aquilegia, Delphinium, Aconitum, etc.
Habit:
Generally the plants are annual or perennial herbs. They perennate either by means of rhizomes or by tuberous roots, e.g., Ranunculus, Aconitum, Paeonia, etc. In many plants the primary root perishes and is replaced by adventitious roots. These roots become tuberous and contain reserve food material in them, e.g., Ranunculus, Aconitum, Paeonia, etc.
A few species are annuals. Undershrub’s, and shrubs are also found in this family. Usually the species of Clematis are climbing undershrub’s. The species of Naravelia are also climbing shrubs.
Leaves:
The leaves are alternate, exstipulate and more or less divided. In some cases the leaves may be opposite or even radical. In Clematis, the leaves are opposite and compound. They possess twining petioles. In Clematis aphylla the whole leaf becomes modified into a tendril.
In the case of Naravelia, the leaves are compound and trifoliate, here the terminal leaflet becomes modified into a tendril. In Anemone the leaves are radical.
The leaf base usually broadens into a sheath which sometimes elongates into a pair of lateral stipules, e.g., in Thalictrum. The leaves of Thalictrum foliolosum are pinnately decompound with auricled sheaths. The leaf lamina is sometimes entire. It is narrow in some species of Ranunculus, however, in Ranunculus ficaria and Caltha sp., it is cordate.
Heterophylly is found in the aquatic species of Ranunculus. In such cases the submerged leaves are very much dissected whereas the floating ones are simply lobed. In Delphinium the leaves are palmately lobed and much dissected. The leaves of Clematis are climbing.
Inflorescence:
In most cases the inflorescence is of cymose type, e.g., Ranunculus. However, in some species of Ranunculus the flowers are found to be arranged in panicles. The flowers are often solitary and terminal, e.g., Anemone sp. In Anemone vitifolia the flowers are arranged in decompound cymes.
In Aconitum and Delphinium, the inflorescence is of racemose type. In Clematis cadmia the inflorescence is solitary axillary. In the species of Nigella, in the beginning a terminal flower is formed but later on the raceme develops.
Flower:
The flowers are ebracteate rarely bracteate, hermaphrodite and mostly actinomorphic (regular), rarely they are zygomorphic (irregular) such as Delphinium and Aconitum, hypogynous and sometimes a disc is found below the gynoecium, e.g., Paeonia. The flowers are usually developed on an elongated receptable. The floral parts being arranged wholly or partly spirally.
Perianth:
In most of the flowers of this family, the perianth is not distinguished into calyx and corolla. It is simple, petaloid and variously coloured. However, in Ranunculus there are two distinct whorls of calyx and corolla, each consisting of five sepals and five petals respectively. The perianth is often associated with nectar secreting structures of various forms.
In Ranunculus, the petals possess pocket like nectaries at their bases. The nectaries are supposed to be the modification of the petals. In certain genera the nectaries develop in the association of sepals, stamens or even carpels. The number of perianth leaves varies from 4 to 20.
Androecium:
Usually the number of stamens is indefinite. The stamens are free (polyandrous). They are hypogynous and arranged spirally. Mostly the anthers are extrorse basifixed and dithecous. They dehisce laterally.
Gynoecium:
It consists of indefinite carpels (polycarpellary), the carpels are free, i.e., apocarpous. In Delphinium the number of carpels is reduced to one. In Aconitum sp., there are three to five carpels. In Nigella, there are 5 to 8 carpels, which are more or less united (i.e., syncarpous). In each ovary the number of ovules ranges from one to many. The ovules are anatropous. The placentation is either marginal (e.g., Delphinium), or basal (e.g., Ranunculus).
Fruit:
The fruit is usually either an etaerio of achenes, e.g., Ranunculus or an etaerio of follicles, e.g., Aconitum. In Actaea, it is a berry. In Nigella it becomes capsule, because of the fusion of carpels. In some of the cases the achenes possess long persistent feathery styles which help in the distribution of the fruits by means of wind, e.g., Clematis and Anemone.
The seeds of Helleborus are disseminated by ants. The ants are attracted by the oil-containing swellings on the raphe. The fruits of certain species of Ranunculus possess hooks and are distributed by animals and birds.
Seeds:
The seeds are endospermic. Each seed contains only endosperm with a very small embryo.
Pollination:
The pollination takes place either by means of insects (entomophily) or by wind (anemophily). In Ranunculus and others the flowers are generally protandrous. In Thalictrum and Helleborus the flowers are protogynous, whereas, in Anemone and Trollius the flowers are homogamous.
The flowers of some species of Thalictrum are wind pollinated but most of the other genera are insect pollinated. The flowers of Delphinium and Aconitum are pollinated by long tongued bees.
Economic value:
Grown as on ornamental. It is poisonous.
Description of some important plants in semi-technical language:
1. Aquilegia vulgaris Linn:
Habit:
Annual or perennial herbs.
Root:
Tap and branched.
Stem:
Erect, herbaceous, aerial green, branched, cylinderical, glabrous.
Leaf:
Cauline and ramal, simple, petiolate, much dissected, entire, lobes with acute apices, stipulate, membranous stipules fused with leaf base, multicostate reticulate venation.
Inflorescence:
Cymose.
Flower:
Pedicellate, bracteate, hermaphrodite, complete, zygomorphic, hypogynous, nectar secreted in spurs of petals, pentamerous.
Calyx:
5 petals, polysepalous, petaloid, imbricate aestivation.
Corolla:
5 petals, polypetalous imbricate aestivation, nectar secreted in spurs of petals.
Androecium:
Indefinite, polyandrous, filament long, anthers dithecous, extrorse, basifixed.
Gynoecium:
5 carpels, apocarpous, carpels are connate in a five-chambered ovary, ovary superior.
Fruit:
Follicle, made up of 5 loose follicles.
2. Clematis paniculatea Thunb:
Habit:
A climber, annual or perennial.
Root:
Tap and branched.
Stem:
Herbaceous, aerial weak, climbing with the help of tendrilar petioles, branched, solid, smooth and green.
Leaf:
Cauline and ramal, simple, petiolate, petiole tendrilar, exstipulate, opposite decussate, ovate, acute, entire, glabrous, unicostate reticulate, coriaceous.
Inflorescence:
Cymose, dichasial cyme.
Flower:
Pedicellate, bracteate, bracteolate, complete, actinomorphic, hermaphrodite, tetramerous, hypogynous, hemicyclic and scented.
Calyx:
4 sepals, polysepalous, valvate, petaloid, white.
Corolla:
Absent.
Androecium:
Indefinite, polyandrous, filamens long, monothecous, extrorse, basifixed.
Gynoecium:
4-6 carpels, apocarpous, ovary superior, unilocular, basal placentation, style short, stigma simple, hairy outgrowths arise from ovary.
Fruit:
Achene.
3. Ranunculus scleratus: Verna-Shim:
Habit:
Annual herb.
Root:
Tap, branched.
Stem:
Erect, reduced in early stages, herbaceous, green, glabrous, solid, branched, aerial with nodes and internodes.
Leaf:
Simple, petiolate, radical with long petioles, tripartite or trilobed, each lobe further divided with obovate, cuneate segments, membranous stipules fused with the leaf base, multicostate reticulate venation.
Inflorescence:
Cymose.
Flower:
Pedicellate, bracteate, hermaphrodite, complete, actinomorphic, yellow and hypogynous.
Calyx:
Five, polysepalous, petaloid, quincuncial, i.e., imbricate in bud condition.
Corolla:
Five, polypetalous, yellow, oblong, pocket-shaped nectary present at the base of each petal, imbricate.
Androecium:
Indefinite, the stamens arranged spirally, polyandrous, filaments long, anthers extrorse, elongated, yellow and basifixed.
Gynoecium:
Indefinite (polycarpellary), apocarpous, ovary superior, unilocular, basal placentation.
Fruit:
An etaerio of single seeded achenes.
4. Delphinium ajacis; Eng.- Rocket larkspur:
Habit:
Annual herb.
Root:
Tap, branched and fibrous.
Stem:
Erect, herbaceous, green, branched, cylindrical, glabrous and fistular.
Leaf:
Simple, cauline, much dissected, lobes linear with acute apex, sessile, exstipulate, multicostate reticulate venation.
Inflorescence:
Racemose, typical raceme.
Flower:
Pedicellate, bracteate, bracteolate (two bracteoles, hermaphrodite, complete, zygomorphic, hypogynous and violet coloured.
Calyx:
Five, polysepalous, petaloid, violet coloured, posterior sepal forms a long spur, quincuncial aestivation.
Corolla:
Four, gamopetalous, the two posterior petals are smaller and produced into a long spur which enters into the spur of posterior sepal and the remaining two lobes which are large in size enclose the essential organs, imbricate.
Androecium:
Indefinite, stamens arranged spirally in five groups of three stamens each alternating with the petals, polyandrous, filaments flattened at base, basifixed anthers, dehisce by lateral slits.
Gynoecium:
One (monocarpellary), ovary superior, unilocular, pubescent, marginal placentation.
Fruit:
A follicle.
Economic Importance of Family – Ranunculaceae:
The family is of little economic value. Many plants are grown in the gardens as ornamentals. Some are of medicinal importance.
A list of few important plants is given below:
1. Aconitum chasmanthum; Verna.-Banbalnag-A herb. Its tuberous roots are the source of a drug known as aconite. This drug is used externally for rheumatism and internally to relieve pain and fever; usually found in Western Himalayas.
2. Aconitum heterophyllum; Verna.-Atis—It is found in the Himalayas. The roots of this plant are used medicinally they are astringent, tonic and used in cough and diarrhoea.
3. Anemone pulsatilla-They are found in Europe and Russia. This is a herb, which yields a medicine known as Pulsatilla. This medicine is given for the treatment of nervous and menstrual trouble of women.
4. Clematis paniculata; A shrub, grown as an ornamental for its beautiful flowers.
5. Clematis triloba; Verna-Murhari-It yields a medicine which is used for the treatment of leprosy and other blood diseases.
6. Delphimum ajacis; Eng.-Rocket Larkspur-This is native of South Europe. The plants are grown in the gardens as ornamentals. The seeds are insecticidal.
7. Delphinium brunonianum; Eng.-Musk larkspur; Verna.-Laskar. The juice of leaves is used as an insecticide. This is found in the Western Himalayas.
8. Delphinium caemleum; Verna.-Dhakangu-The root is used as an insecticide to kill maggots in the wounds of goats.
9. Delphinium denundatum; Verna-Nirbisi-The roots are used as a tonic.
10. Nigella damascena- Eng.-Love-in-a mist.- A herb, grown as an ornamental in the gardens. It is native of South Europe.
11. Nigella sativa; Eng.-Black cumin; Verna.-Kala jira, Kalonji-The seeds are used as condiment and spice. The seeds mixed with sesamum oil are used externally in eruption of skin and for scorpion sting. The seeds are stimulant, carminative and diuretic. It is a herb. The plants are cultivated in the Punjab, Assam, Bihar and Bengal.
12. Ranunculus aquatilis; Verna.-Jal dhania-It is used medicinally in the treatment of rheumatic pain and asthma.
13. Ranunculus ficaria; Eng.-Pilewort-The plant is native of Europe. It makes a good medicine of piles. The patent medicine of piles, known as pilewort ointment’ is prepared from this plant.
14. Thalictrum foliolosum; Verna.-Mamira-The roots are used as a tonic. The plants are found in the Himalayas.
15. Thalictrum javanicum; This plant is the alternate host of brown rust of wheat, caused by Puccinia recondita.