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Tuesday, 3 March 2009

FAMILY OF THE WEEK : ZINGIBERACEAE


Hitchenia caulina


Curcuma longa


Curcuma pseudomontana


Curcuma neilgherrensis

FAMILY OF THE WEEK : ZINGIBERACEAE

A family of 45 genera and 750 species distributed in the tropical regions chiefly Indo Malaysia. In India there are 17 genera and 112 species occurring in Eastern Himalayas and Western ghats.

Vegetative characters:

They are perennial herbs with creeping, horizontal or tuberous rhizomes. The plants are usually aromatic.
The aerial stem when present is short and leafy or scapose and bearing only flowers as in Curcuma and Zingiber. The leaves are basal or cauline and are in two rows. They have a sheathing base and a petiole may or may not present between sheath and blade. The blade is linear to ellipticand often large with numerous closely parallel and pinnate veins diverging obliquely from the midrib. A characteristic ligule is present at the junction of the petiole and blade.

Inflorescence and flowers:

The inflorescence is either terminal on the leafy shoot or on a scale leaf bearing scape(Curcuma) or produced directly from the rootstock at the base of the stem(Amomum).It is a spike (Curcuma) or a dense head(Costus) or panicle.Sometimes the flowers are solitary as in Gastrochilus.
The flowers are bracteate and the bracts are often coloured and distichous or spirally arranged. They are mostly bisexual, zygomorphic or actinomorphic, trimerous and epigynous. The perianth is of six members in two trimerous whorls. It is differentiated into an outer calyx and and an inner corolla. The three sepals are united into a tube. The odd sepal is anterior. The petals are also more or less united and the three segments are similar or dissimilar and then the posterior segment is usually the largest and covers the edges of lateral segments. The petals are often very showy and delicate. The androecium is of six stamens in two trimerous whorls. The anterior stamen of the outer whorl is always absent while the other two are represented by large and leafy staminodes. The posterior stamen of the inner whorl and the other two are united to form a petaloid labellum which embraces the fertile stamen and is often the most conspicuous part of the flower. The fertile stamen and the staminodes are inserted on the mouth of the corolla tube. The fertile stamen has a slender and deeply grooved filament and a dithecous anther dehiscing vertically. The gynoecium is tricarpellary and syncarpous. The ovary is inferior and trilocular.The style is simple and terminal and is more or less enevoloped in the groove of the filament of the fertile stamen. Sometimes the style is two lipped or dentate. The stigma is simple or capitate.
A pair of nectar secreting epigynous glands are often present.

Fruits and seeds:

The fruit is usually a loculicidal capsule. The seeds are rounded or angular with copious hard or mealy endosperm and straight embryo.

Pollination and dispersal:

The showy flowers favour insect pollination. The fruits are distributed by animals.

Examples:

Zingiber officinale (Ginger, adrak, Ale)
Curcuma
Curcuma longa L. (Turmeric,Haldi)
Curcuma angustifolia Roxb.(East Indian arrowroot, Tikhur)
Curcuma neilgherrensis
Amomum cardamomum (Cardamum,Choti Elayachi)
Elettaria cardamomum (Cardamon, Elaychi)
Hitchenia caulina

Monday, 23 February 2009

FAMILY OF THE WEEK: VITACEAE




Leea indica

FAMILY OF THE WEEK: VITACEAE

It is a small family with 12 genera and 700 species worldwide, distributed in tropics and warm temperate regions of the world. In India there are 8 genera and 95 species occurring in western peninsular India and in the Himalayas.

Vegetative characters:

They are mostly woody vines climbing by means of tendrils or adventitious roots. The tendrils are attached to the substratum by coiling or by adhesive discs. Species of Leea are small trees, shrubs or herbs. The stem is usually sympodial. The stem is angle compressed or cylindrical with numerous very large vessels, swollen or jointed nodes and watery juices. The leaves are alternate or the lower leaves are sometimes opposite, simple or palmately or rarely pinnately compound as in Leea. They are often pellucid punctuate and with deciduous stipules.

Inflorescence and flowers:

The numerous flowers are usually arranged in leaf opposed spikes, racemes, panicles or cymes. Occasionally the peduncles are flattened and expanded (Pterisanthes). Some peduncles are often transformed into tendrils or viscid discs which adhere to the substratum. The flowers are bracteates, hermaphrodite, rarely unisexual, actinomorphic, tetra or pentamerous and hypogynous. The calyx is small, four or five toothed or lobed or reduced to an inconspicuous ring. The corolla has four or five petals which are free or united. The petals generally fall when the flowers open. The androecium is of four or five stamens which are opposite the petals and are inserted at the base of the disc or between the lobes. The filaments are short, subulate and free or connate at the base (Leea). The anthers are free or connate, dithecous, introrse and open by the longitudinal slits. An annular or variously expanded nectariferous disc is present which is free or connate with the petals, stamens or ovary. The gynoecium is two to six carpellary and syncarpous with a superior and two to six locular ovary. The style is short slender and conical or absent and the stigma is capitates, discoid or sublobed.

Fruits and seeds:

The fruit is one to six chambered juicy berry with one or two seeds in each chamber. Seeds have a cartilaginous endosperm and a short basal embryo.

Pollination and dispersal:

The Vitaceae are insect pollinated.

Examples:

Vitis vinifera (Grape vine)

Leea indica (Dinda)

Leea macrophylla

Cissus adnata

Cissus woodrowii

Parthenocissus

Ampelopsis

Tuesday, 17 February 2009

FAMILY OF THE WEEK : VERBENACEAE


Tectona grandis(Teak)

Clerodendrum multiflorum


GmelinaArborea(shivan)


Clerodendrum serratum(Bharangi)


Petrea volubilis


Clerodendrum viscosum


Citharexylum quadrangulare


FAMILY OF THE WEEK : VERBENACEAE
A large family mostly distributed in tropical and subtropical regions. In India it is represented by 21 genera and 125 species occurring mostly in southern and western India and the tropical and subtropical Himalayas.
Vegetative characters:
Mostly annual or perennial herbs, sometimes shrubs or trees and rarely woody climbers(Petrea). Avicennia is a mangrove shrub or small tree.
The stem is often quadrangular and increases in thickness by formation of concentric rings of cambium. The leaves are usually opposite or whorled, exstipulate, simple or rarely pinnately or palmately compound.
Inflorescence and flowers :
The Inflorescence may be cymose, racemose or spicate. The cymes are often compound or panicled as in Tectona. The bracts and bracteoles are usually present.
The flowers are bisexual or sometimes polygamous by abor, more or less zygomorphic, usually pentamerous and hypogynous. The calyx is gamosepalous, persistent and usually five toothed or lobed. The corolla is gamopetalous, tubular and the tube often cylindric, limb bi lipped or unequally five lobed. The lobes are imbricate in bud. The stamens are four didynamous and epipetalous on the corolla tube. The anthers are dithecous, introrse and opening lengthwise. The gynoecium is bicarpellary and syncarpous. The ovary is superior with as many locules as the number of carpels. The stigma has as many lobes as the number of carpels.
Fruits and seeds :
The fruit is a drupe with one seeded pyrenes. The seeds have a straight embryo and are nonendospermic or with scanty endosperm.
Pollination and dispersal :
Mostly pollinated by bees and butterflies.The seeds are dispersed by birds and animals.
Examples :
Tectona grandis (Teak, Sag)
Premma bengalensis
Vitex altissima
Vitex negundo
(Nirgudi)
Gmelina arborea
(Shivan)
Lantana camara

Duranta repens

Petrea volubilis

Clerodendrum

Holmskioldia sanguinea
(Chinese hat plant)
Caryopteris incana.
Citharexylum quadrangulare

Wednesday, 11 February 2009

FAMILY OF THE WEEK: TILIACEAE


Grewia hirsuta



Grewia flavens

FAMILY OF THE WEEK: TILIACEAE

Chiefly distributed in tropical and temperate regions, in southeast Asia and Brazil. In India there are 14 genera and more than 110 species, found mostly in warmer parts.

Vegetative characters:
They are mostly trees or shrubs, sometimes herbs. The stems often have strong phloem fibre. The plants are usually covered with stellate hairs.
The leaves are usually alternate, often showing a distinct distichous arrangement, simple, entire or lobed. The blade is usually oblique with the larger side towards the branch. The stipules are free and often caducous and fall as the bud unfolds.

Inflorescence and flowers:
The flowers are usually arranged in cymose inflorescences which are axillary or terminal and few to many flowered. The flowers are complete, usually hermaphrodite, actinomorphic and hypogynous. The calyx is of mostly five, free or connate sepals which are valvate in bud. The corolla has as many petals as the sepals. the petals are free and show imbricate or valvate aestivation in bud. They are often glandular at the base.
The androecium has ten to numerous stamens, arising from a disc; distinct or basally connate in five bundles. The filaments are filiform and the anthers are dithecous, introrse and opening by a longitudinal slit or by an apical pore. In Grewia the stamens are raised by the development of an internode between the petals and the stamens.
The gynoecium is two to ten carpellary with a superior and sessile ovary.

Fruits and seeds:
The fruit is fleshy or dry and dehiscent or indehiscent. the seeds are endospermic with a straight embryo.

Pollination and dispersal:
The pollination is by insects. The fruits of Grewia are edible and the seed dispersal is by animals. In Triumfetta the fruits are adhesive and develop spines and thus attach to humans and animals.

Examples:

Corchorus capsularis (Jute)
Grewia
Triumfetta
Tilia

Wednesday, 4 February 2009

FAMILY OF THE WEEK: STERCULIACEAE


Sterculia foetida



Firminia colorata


Eriolaena quinquelocularis


Sterculia alata


Gauzuma


Dombeya


Pterospermum acerifolium

FAMILY OF THE WEEK: STERCULIACEAE

Family chiefly of tropics. There are 18 genera and more than 90 species mostly in tropical areas while some are in Himalayas.
Vegetative characters:
Mostly soft wooded trees or shrubs, sometimes herbs, rarely climbers. The younger parts are often stellate, tomentose. The bark is mucilaginous and the inner often fibrous. The leaves are alternate or rarely subopposite, simple, entire, palmately lobed or digitate(Sterculia). The petiole is often pulvinate. Stipules present usually caducous.
Inflorescence and flowers:
Inflorescences are axillary or sometimes terminal complex cymes. The flowers are hermaphrodite or unisexual or polygamous, actinomorphic, pentamerous and hypogynous. The calyx has five sepals, valvate more or less united, often coloured(Sterculia).Corolla has five petals. They are absent in Sterculia, free or adnate to the base of the staminal tube. They are deciduous or sometimes persistent(Dombeya). Androecium has few to many stamens which are free or often connate in tube. Gynoecium is 2-5 carpellary and syncarpous with a superior ovary, sessile or raised with androgynophore. The style is simple or lobed or rarely divided upto the base
Fruits and seeds:
Fruits are dry / fleshy, dehiscent/indehiscent. Seeds endo/nonendospermic with a straight or a curved embryo.
he seeds are numerous, compressed, discoid or subreniform, endospermic and with a curved or straight embryo.
Pollination and dispersal:
Pollination is by insects. Winged seeds of Dombeya and Pterospermum favor wind dipersal of seeds. It also takes place by animals and birds.
Examples:
Sterculia Pterospermum
Helicterus

Dombeya

Theobroma cacao
(Coco tree)
Cola acuminata
Gauzuma ulmifolia

Firminia colorata
Eriolaena quinquelocularis

Friday, 30 January 2009

FAMILY OF THE WEEK: SOLANACEAE





FAMILY OF THE WEEK: SOLANACEAE (NIGHTSHADE FAMILY)
A large family with over 2000 species worldwide. In India there are 15 genera and 88 species. Many species are cultivated while others occur chiefly in Himalayas and southern and eastern parts of India.
Vegetative characters:
They are mostly annual or perennial herbs, sometimes shrubs or small trees and rarely climbers. The stems are prickly or spinous, the spines are modified branches. The vascular bundles are bicollateral. Underground tubers are found in Solanum tuberosum. The leaves are alternate,exstipulate, simple,entire, lobed or pinnatified. In the inflorescence portion the leaves often become subopposite or opposite.
Inflorescence and flowers:
Often cymes which are lateral, axillary or terminal. In some species of Solanum they are extraaxillary appearing to arise from the middle of an internode. Very frequently they are solitary and axillary as in Datura and Nicardia and rarely clustered as in Withania. The bracts and bracteoles are absent.
The flowers are actinomorphic or sometimes zygomorphic, bisexual, pentamerous and hypogynous. The calyx is five lobed or five partite and usually persistent and much enlarged in fruit. The corolla is gamopetalous and funnell shaped(Datura) campanuloate(Physalis) or rotate(Solanum) The limb is usually five lobed or rarely ten lobed as in Datura and the lobes are folded contorted or valvate. The stamens are usually five,epipetalous on the corolla tube and alternate with the lobes. They are commonly of unequal heights. The anthers are ovate or oblong, sometimes connivant into a cone as in Solanum, dithecous,introrse and dehiscing by longitudinal slits or by apical pores.(Solanum)
Thhe gynoecium is typically bicarpellary and syncarpous. The ovary is superior and bilocular with axile placentation.The style is linear and the stigma is capitate or shortly lobed.
A hypogynous nectariferous disc is usually present at the base of the ovary.
Fruits and seeds:
The fruit is a berry which is sometimes (Physalis)enclosed within an inflated bladder-like calyx or capsule. The seeds are numerous, compressed, discoid or subreniform, endospermic and with a curved or straight embryo.
Pollination and dispersal:
Conspicuous flowers and nectariferous disc favor insect pollination. Solanum tuberosum is devoid of nectar and is scarcely visited by insects. Here usually self pollination occurs by the style curving backwards to touch the anthers.
The seeds are usually dispersed by birds and animals.Species of Datura,Atropa and Hyoscyamus are dispersed by water.
Examples:
Solanum tuberosum (Potato, Batata)
Solanum melongena (Egg plant,Brinjal,Baingan,Wang) Lycopersicon esculentum(Tomato)
Capsicum annuum
(Chillies, Mirch)
Nicotiana tobacum
(Tobacco)
Atropa belladonna
(Belladonna)
Hyoscymus niger
Datura stramonium
Withania somnifera
(Ashwagandha)
Withania coagulans (Indian rennett)
Petunia

Wednesday, 21 January 2009

FAMILY OF THE WEEK: SCROPHULARIACEAE


Rhamphicarpa

Verbascum chinens

Lindernia ciliata

FAMILY OF THE WEEK: SCROPHULARIACEAE
This family is cosmopolitan in distribution but most abundant intemperate regions. In India it is represented by 57 genera and 350 species occurring chiefly in Himalayas.
Vegetative characters:
Mostly annual or perennial herbs, sometimes shrubs (Veronica) or rarely trees(Wightia). Certain members are aquatic(Limnophila) or marsh (Departrium and Herpestis) Some are chlorophyll containing hemiparasites(Pedicularis and Striga) or parasites without chlorophyll as Lathraea.
Usually the lower leaves are opposite and upper alternate.They are simple exstipulate entire or pinnately lobed or incised.
Inflorescence and flowers:
Variable but commonly racemose or spicate. Sometimes cymose or axillary solitary.The bracts and bracteoles are usually present.
The flowers are perfect, hermaphrodite,zygomorphic or sometimes as in Verbascum nearly actinomorphic and hypogynous.The calyx is deeply five lobed or divided, persistent, imbricate or valvate. The corolla is gamopetalous and the limb is usually free and more or less bi-lipped.Commonly five stamens are fertile and the fifth is reduced to a staminode or is completely absent.The stamens are epipetalous. the anthers are dithecous but occasionally the two cells are unequal or only one cell is present. The gynoecium is bicarpellary and syncarpous with a superior bilocular ovary. The style is simple and the stigma is capitate, bilobed or bi-lamellate.
An annular or cup shaped nectariferous disc is present at the base of the ovary which is sometimes bilobed.
Fruits and seeds:
The fruit is a capsule or rarely a berry. the seeds are small with a fleshy endosperm and straight or slightly curved embryo.
Pollination and dispersal:
The flowers are adapted for insect pollination. The seeds are dispersed by water, birds or animals.
Examples:
Antirrhinum majus (Snapdragon)
Digitalis purpurea (Common foxglove)
Linaria vulgaris
Verbascum chinens
Rhamphicarpa
Lobelia nicotianifolia(Ran Tambaku)
Lindernia ciliata

Thursday, 15 January 2009

FAMILY OF THE WEEK: SAPOTACEAE





Achras sapota

Mimuseps elengi

FAMILY OF THE WEEK: SAPOTACEAE

In India there are 10 genera and 52 species occurring mostly in North Eastern and Southern India.

Vegetative characters:

They are trees or shrubs with young parts often rusty tomentose. The plants contain a milky juice. The leaves are alternate or rarely subopposite, simple, entire,petioled and coriacious and leathery. The stipules are usually absent.

Inflorescence and flowers:

The flowers are solitary or in cymose clusters in the leaf axils. They are bisexual, actinomorphic and hypogynous. The calyx has four to eight sepals which are united at the base. They are arranged in two or one series. The corolla is gamopetalous but the corolla tube is shorter than the calyx tube. The corolla lobes are usually as many as the calyx lobes and alternate with them and sometimes twice as many as the calyx lobes. The petal lobes are imbricate in bud.

The stamens are inserted upon the corolla tube. They are usually as many as the corolla lobes and opposite to the corolla lobes. Sometimes the stamens are two to three times as many as the corolla lobes and then they are two or three seriate. The outer stamens are sometimes reduced to staminodes as in Mimusops. The filaments are usually short. The anthers are oblong lanceolate, dithecous and extrorse. The connective is often produced beyond the anthers. The gynoecium has two to eight syncarpous carpels. The ovary is superior with as many locules as the number of carpels. The style is one, often apically lobed.

Fruits and seeds:

The fruit is one to eight seeded berry. Latex sacs are also present in the inner pulp of the berry. The seeds are often compressed with a crustaceous testa. The embryo is straight.

Pollination and dispersal:

Pollination is by insects. Fruits are distributed by birds and animals and water currents.

Examples:

Achrus sapota (Sapodilla plum)

Manilkara hexandra

Madhuca indica

Mimuseps elengi (Bakul)

Friday, 9 January 2009

FAMILY OF THE WEEK: SAPINDACEAE


Schleichera oleosa (Kusam)


Sapindus


Sapindus

FAMILY OF THE WEEK: SAPINDACEAE ACERACEAE(MAPLE FAMILY)
Large family represented in India by 24 genera and 72 species occurring in the tropical eastern Himalayas and western peninsular India.
Vegetative characters:
The members of the family are trees or shrubs or sometimes vines. The stems show peculiar secondary growth in thickness.
The leaves are alternate or rarely opposite (Acer), usually pinnately compound, sometimes simple (Cardiospermum), palmately lobed and veined (Acer) or digitate (Aesculus). They are exstipulate but occasionally stipulate as in Melianthus. The latex or resin cells are often present in the leaves.
Inflorescence and flowers:
Racemose inflorescence with minute flowers or unilateral cymes in panicles. The flowers are mostly polygamo-dioecious. They are zygomorphic or occasionally actinomorphic, tetra or pentamerous and hypogynous.
The calyx is composed of four or five sepals which are free or variously connate, often unequal and valvate or imbricate in bud.
The corolla is of four to five free petals but usually there are four petals and the place of fifth petal is vacant.
The androecium has typically eight or ten stamens or sometimes less as in Aesculus.
An annular or unilateral disc is often present between the petals and the stamens.
The gynoecium is usually tricarpellary and syncarpous. The ovary is superior.
Fruits and the seeds:
The fruit is capsular or it is indehiscent and entire or lobed as in Sapindus. Sometimes the fruit is a double Samara as in Acer or nutlike as in Litchi.
The seeds are globose or compound, often arillate, endospermic or nonendospermic with often plicate or spirally convolute embryo.
Pollination and dispersal:
The flowers are often protandrous and pollinated by insects. Flies and humble bees are the chief pollinators.The fruits of Dodonia and Acer are blown to long distances by strong winds. The dispersal also takes place by birds and animals in many genera.
Examples:
Litchi chinensis
Sapindus mukorossi (Soapnut tree, Ritha)
Sapindus laurifolius Acer saccharinum (Sugar Maple)
Aesculus hippocastanum (Horse chestnut)
Schleichera oleosa (Kusam)
Dodonia viscose (Vilayati Mehandi)
Nephelium lappaceum (Rambutan)