In this article we will discuss about:- 1. Characters of Violaceae 2. Distribution of Violaceae 3. Economic Importance 4. Affinities 5. Important Type.

Characters of Violaceae:

Plants mostly herbs rarely shrubs, all leaves basal, simple, stipulate; flowers zygomorphic rarely actinomorphic, hermaphrodite, hypogynous; sepals, petals and stamens 3 each; gynoecium tricarpellary, syncarpous, unilocular with parietal placentation; fruits capsule.

A. Vegetative characters:

Habit:

Mostly herbs – annual or perennial, some shrubs or under-shrubs rarely climbers (Anchietea).

Root:

Tap, root.

Stem:

Herbaceous or woody, erect, usually un-branched.

Leaf:

Simple, entire or variously toothed, with a marked tendency to be cordate in form, all basal in some species, but in others alternate or rarely opposite (Hybanthus), stipulate, stipules permanent and foliaceous (Viola spp.).

B. Floral characters:

Inflorescence:

Solitary or terminal spike.

Flower:

Bracteate, bracteolate (two bracteoles), perfect, regular (Rinorea syn. Alsodeia) or irregular (Viola, with a large spurred anterior petal), pentamerous, hermaphrodite or rarely polygamous, hypogynous, sometimes cleistogamous.

Calyx:

5 sepals, free or somewhat connate to form a ring around the ovary. Sepals appendiculate, prolonged below into a short obtuse blade.

Corolla:

5 petals, free, equal or unequal, the lowest (anterior) one often large and saccate or spurred, variously coloured.

Androecium:

Stamens 5, joined in a ring around ovary and style; anthers introrse, connectives of anterior stamens spurred, the spurs enter the spur, formed by the anterior petal.

Gynoecium:

Carpels 3, rarely 2-5 (Melicystus, Leonia), syncarpous unilocular with parietal placentation, ovules one to numerous on each placenta; style simple or divided; stigmas of various shapes, often hooded.

Fruit:

A loculicidal capsule.

Seed:

Endospermic, smooth, winged, testa shining.

Pollination:

Entomophilous; cleistogamous flowers (Viola tricolor) are self pollinated.

Floral formula:

Distribution of Violaceae:

Violaceae or violet family comprises of 22 genera and approximately 900 species, which are widely distributed in all continents. In India it is represented by 3 genera – Viola, Vahila and Hybanthus.

Economic Importance of Violaceae:

1. Medicinal:

The dried flowers of Viola odorata (Vern. Banafsha) are used against cough, influenza and respiratory diseases, Roots of Hybanthus enneaspermus are used in urinary infections and gonorrhoea.

2. Oil:

Oil extracted from flowers of Viola odorata is used in perfumes, while its leaves yield an essential oil, used in scenting soaps.

3. Ornamentals:

Violas, violets (Viola odorata) and pensies (V. tricolor) are commonly cultivated in gardens for their beautiful and colourful flowers.

Affinities of Violaceae:

The phylogenetic position of family is uncertain. Wettstein, Bentham and Hooker placed it in the order Parietales. Rendle included in Guttales. Hellier opioned that the Violaceae is akin to Balsaminaceae; Flacourtiaceae and Turneraceae due to the spurred corolla and thus included it as a primitive member of his Polygalines. Hutchinson placed it in the Violales.

Common plants of the family:

1. Viola odorta L.:

Sweet violet or wild pansy – an ornamental plants.

2. Viola canina:

Dog violet. Cultivated; leaves used in pulmonary troubles.

3. Hybanthus (Syn. lonidium) enneaspermus:

Roots used for intestinal disorders of children.

Division of family and chief genera:

Violaceae is divided into to sub-families:

Sub-family I. Leoniodeae:

Stamens connate forming a column. Fruit nut-like with hard pericarp. Example – Leonia.

Sub-family II. Violoideae:

Stamens free or more of less connate; fruit – a capsule. Example- Viola.

Important Type of Violaceae:

Viola tricolor (Pansy; Fig 33.1):

Viola Tricolor

Habit:

Annual garden plant.

Root:

Tap-root.

Stem:

Erect, branched, angular, green, fistular, herbaceous.

Leaf:

Cauline and ramal, simple, alternate, stipulate, stipules leafy, unicostate reticulate; crenate, acute, glaucous.

Inflorescence:

Solitary axillary.

Flower:

Bracteate, two bracteoles, pedicellate, complete, hypogynous, hermaphrodite, zygomorphic, colour variable.

Calyx:

5 sepals, free, quincuncial, green, inferior, sepals appendiculate.

Corolla:

5 petals, polypetalous, imbricate, anterior petal produced into a spur, in which the honey produced by the spurs of the connectives of two anterior stamens is collected.

Androecium:

Stamens 5, connate, forming a ring around the ovary, filaments small, anthers adnate, connectives of anterior pair of stamens are spurred, which project into the spur of the anterior petal.

Gynoecium:

Carpels 3, syncarpous; ovary superior, unilocular with numerous ovules attached to parietal placentae; style short, filiform; stigma swollen.

Fruit:

A loculicidal capsule.

Seeds:

Numerous, ovoid, tough and smooth.

Floral formula:

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