Study of Family Urticaceae

Systematic position/ Classifications:

Venation reticulate, 2 cotyledons                                        Class- Dicotyledons

Flowers incomplete, mostly unisexual, small,

green, Perianth 1-seriate, only one whorl present           Subclass- Monochlamydeae

Flowers unisexual, Perianth lobes sepaloid absent,

gynoecium with free styles, seeds endospermic               Order- Unisexuales

                                                                                                Family- Urticaceae   

Distribution: Members of this family are distributed mainly in tropical regions of the world with 480 species and 41 genera.

Salient features:

Plants are generally fibrous herbs, with stinging hairs (Urtica, Girardinia), latex is absent.

Leaves are simple, alternate or opposite, margin entire or serrate, stipules present. Dried leaves with cystoliths.

Flowers are in cymes or heads, monoecious or dioecious, unisexual, Actinomorphic & hypogynous. Pistilate flowers occurs in male flowers and staminodes are present in female flowers.

Perianth green, sepaloid and consists of 4 perianth leaves arranged in whorls of two each, it united in female flowers.

Male flowers- androecium consists of 4 stamens (rarely 3-5), isomerous, filaments inflexed in bud, anthers explode suddenly when ripe after jerk. Some time a rudimentary pistil is also present. In Pilea muscosa pollen grain discharge profusely when plant shakes therefore called as ‘artillary’ or ‘gunpowder plant’.

Female flowers- gynoecium with single carpel, ovary superior, unilocular with single ovule, style is simple ending in a stigma which is with brush like tuft, scale like staminodes are present at the base of pistil. Ovules erect and is of orthotropous type.

Fruits- is an achene or a drupe enclosed by a persistent Perianth. Seeds are endospermic with oily endosperm and straight embryo.

Note-

Floral formula:

Floral diagram:

Morphological peculiarities:

Predominantly herbaceous plants.

Leaves stipulate with cystolyths.

Presence of stinging hairs.

Flowers unisexual, monochlamydous.

Stamens inflexed in buds and inwardly bent when mature.

Stigma brush like.

Placentation basal.

Economic importance & their uses-

Girardinia heterophylla- stem yields a strong silk like fibre which is mainly used in making twine, ropes, some time course cloth, etc.

Boehmeria nivea- It is largely cultivated in China for the bat fibre which is longer, stronger and most silky of all the vegetable fibres.

Mautia, Urtica dioica yields very useful fibre.

Garden Plants- Pilea, Pellionia are grown in pots in garden due to foliage and beautiful flowers.

Edible plants- Trema orientalis fruits are useful for eating purpose.

The wood of Trema is useful in making charcoal for gunpowder.

Present status, affinities, phylogeny & inter-relationship of Urticaceae:

Based on floral and wood anatomy families like Ulmaceae, Moraceae, Urticaceae are treated under one family Urticaceae by Bantham & Hooker’s.

Moraceae and Urticaceae both have unisexual flowers, stamens as many as perianth lobes  and ovary is unilocular.

Engler and Prantl and Hutchinson considered Urticaceae as most advanced family amongst Moraceae and Urticaceae under order Urticaless.

                                  Study of Family Bignoniaceae

Systematic position/ Classifications:

Venation reticulate, 2 cotyledons                                        Class- Dicotyledons

Perianth with distinct petals & sepals, petals fused          Subclass- Gamopetalae

Flowers hypogynous, stamens equal to number of petals,

gynoecium superior, bicarpellary                                       Series- Bicarpellatae

Corolla zygomorphic, staminodes

present, ovules more than 4                                                            Order- Personales

                                                                                                Family- Bignoniaceae     

    

Distribution: Members of this family are distributed throughout the world mainly in tropics. There are 650 species from 120 genera.

Salient features:

Plants are mostly shrubs & trees. Tecomeria & Pandorea are lianas.

Leaves are opposite decussate, compound, terminal leaflet modified into tendril, exstipulate and pinnately compound.

Flowers are bisexual, Zygomorphic, hypogynous, bracteates, bracteolate and pentamerous.

Calyx- with 5 sepals, united, campanulate, lobed or bilabiate, valvate aestivation.

Corolla- with 5 petals, united, campanulate, imbricate aestivation, obliquely campanulate or infundibulliform, lobes 5, sometime bilabiate.

 Androecium- with 4 stamens, didynamous, 5^th epipetalous, posterior one is reduced to staminodes 2 (Catalpa). Anthers are dithecous, introrse dehiscing by longitudinal placentae.

Gynoecium- is bicarpellary, syncarpous, superior; style terminal; stigma forked, bifid numerous anatropous erect ovules attached to axile placenta.

Fruit- is a 2-valved septicidal or loculicidal capsule or berry. Seeds non-endospermic, flattened, winged, sometime comose in Chilopsis.

Note-

Floral formula:

Floral diagram:

Morphological peculiarities:

Plants arborescent (i.e. trees/shrubs).

Leaves compound.

Flowers Zygomorphic with bracts & bracteoles.

Presence of posterior Staminode.

Antherlobes divergent & seemingly one above the other.

Fruits capsule with winged seeds.

Economic importance & their uses-

Ornamental plants:

Spathodia campanulata (Pichkari)- A native to Tropical Africa.  

Jacaranda mimosifolia (Neel Mohar)- A native of Brazil & Argentina.

Bignonia-

Tecoma stans (Yellow Bell)- A native to Tropical South America.

Kigelia pinnata (Bramhadanda)- A native to Tropical Africa.

Millingtonia hortensis (Cork tree or Akashneem)-a native to S.E. Asia & Malesia.

Tabebuia argentia & T. rosea- A native to Paraguay

Wild plants-

Heterophragma quadriloculare (Varas)

Dolichandron falcata (Medshingi)

Oroxylum indicum (Tetu)

Pagenali longifolia

Radermachera xylocarpa

Sterospermum chelenoides (Padal)

Present status, affinities, phylogeny & inter-relationship of Bignoniaceae:

Bessey placed this family in Scrophulariales, the origin of which was traced from Polemoniales. Hallier included it in order-Tubiflorae and placed it near Pedaliaceae and Acanthaceae. Hurchinson put it under 53^rd Order Bignoniales. According to Hutchinson Bignoniales originated from Loganiales.

Study of Family Plumbaginaceae

Study of Family Plumbaginaceae

Systematic position/ Classifications:

Venation reticulate, 2 cotyledons                                        Class- Dicotyledons

Corolla partially / completely

fused                                                                                       Subclass- Gamopetalae

Stamens in two or more series

as per petals, epipetalous, ovary

superior, carpels more than two                                        Series- Heteromerae

Stamens equal to petals, ovary

with 2-many locules                                                              Order- Primulales

Flowers fragrant, corolla rotate,

stamens epipetalous, fruits berry                                       Family- Plumbaginaceae

Distribution: Mainly distributed in tropical and subtropical parts of the world.

Note: Plumbago zeylanica is commonly known as Ceylon leadwort, doctor bush or wild leadwort.

Description:

Habit- Plants are herbaceous

Stem- glabrous stems, climbing, prostrate, or erect.

Leaves- are petiolate or sessile, ovate, lanceolate, elliptic or spatulate to oblanceolate 5-9 × 2.5–4 cm. Bases attenuate; apex acute, acuminate or obtuse.

Inflorescences- Flowers in 3–15 cm long spike and have glandular, viscid rachises. Bracts are lanceolate, 3-7 × 1–2 mm long. The heterostylous flowers have white corollas 17–33 mm in diameter and tubes 12.5–28 mm in length.

Fruits- Capsules, 7.5–8 mm long, with reddish brown to dark brown seeds

Current Status: Species of plumbago with apantropical distribution. Carl Linnaeus described the paleotropical P. zeylanica and neotropical P. scandens as separate species, but they are currently considered synonymous.

Study of Family Caryophyllaceae

Systematic position/ Classifications:

Venation reticulate, 2 cotyledons                                        Class- Dicotyledons

Perianth with distinct petals & sepals, petals free             Subclass- Polypetalae

Sepals distinct, stamens many,                               

hypogynous disc absent                                                       Series- Thalamiflorae

Placentation free central                                                      Order- Caryophyllineae

                                                                                                Family- Caryophyllaceae     

Distribution: Members of this family are distributed throughout the world especially in temperate regions with 2415 species from 96 genera. In India this family is represented by 105 species and 20 genera. Common species are Stellaria, Saponaria, Spergula, Dianthus,etc. Silene (700 sp.) & Dianthus (300 sp.) are the largest genera.

Salient features:

Plants are annual or perennial herbs. Stem is herbaceous, erect, branched with swollen nodes

.

Leaves are simple, linear to lanceolate, sessile & opposite decussate. In Spergula leaves are dissected from base hence appear in whorled arrangement. Stipules absent, when present it is membranous.

Flowers are in typical dichasial cyme and it becomes monochasial cyme. This development of dichasial to monochasial type of inflorescence is called as cincinnus or caryophyllous type, which is characteristic feature of Caryophyllaceae.  Flowers are solitary in Arenaria & Githago. Flowers hermaphrodite, actinomorphic, pentamerous & hypogynous. In Lychnis flowers are unisexual & tetramerous in Sagina.

Calyx- with 5 sepals, poly or gamosepalous, persistent, imbricate. 4 sepals in Sagina.

Corolla- with 5 or 4 petals, free differentiated into a limb and claw. In Stellaria media petals are deeply bifid and in Dianthus ligulate outgrowth called corona on dorsal surface. In Sagina apetala petals are absent.

Androecium- 1 or 8 stamens. In Stellaria it varies from 3-10, arranged in two whorls, filaments connate.

Gynoecium- with 5 carpels, syncarpous, ovary superior, unilocular with free central placentation. Each placenta with one to many ovules. Presence of elongated disc or gynophores. Some time it consists of glands at base.

Fruit- is a dry capsule opening by valves or teeth. Seeds are small, winged, many, attached to central column, endospermic with curved embryo.

Note-

Floral formula & Floral formula:

Morphological peculiarities:

Annual or perennial herbs.

Flowers in monochasial cyme which become polychasial i.e. cincinnus or caryophyllous type.

Number of sepals and petals are equal.

Stamens 1 or 8, sometime 10 in two whorls.

Ovary with free central placentation and sometime glands at base.

Fruits dry capsule open by valves or teeth.

Economic importance & their uses-

In Medicine- Saponaria, Dianthus are used as medicine. Spergula arvensis used as diuretic. Silene apetala used in eye troubles.

Ornamental plants- Due to beautiful foliage and flowers colour species like Lychnis, Arenaria, Dianthus (D. chinensis-China Pink; D. caryophyllus-Carnations, D. barbatus-Sweet Willium) are ornamentally useful.

Present status, affinities, phylogeny & inter-relationship of Caryophyllaceae:

The origin of this family have some controversy. In this aspect according to Eichler it originates from Phytolaccaceae as petals are evolved from outer whorl of carpels.

According to Hutchinson this family is derived from Ranales or from Primulaceae.

This family is related to Portulacaceae based on resemblance by presenc of unilocular ovary with free central placentation.

Relation with Geraniaceae is due to pentamerous flowers and nature of stamens.

Family is related to other families of order Centrospermae (as all have curved embryo & perisperm in seed).

According to Cronquist family has been derived from Phytolaccaceae in the line Polygonaceae. Therefore he kept it under order Caryophyllales of sub class Caryophyllidae.

Thorne recognized 5 sub-orders within Caryophyllales and placed it under monotypic suborder Caryophyllineae.

As per APG classification it has been placed under the order Caryophyllales of APG group: Core Eudicots, a monotypic familial group

Study of Family Sapotaceae

Systematic position/ Classifications:

Venation reticulate, 2 cotyledons                                        Class- Dicotyledons

Perianth with distinct petals & sepals, petals fused          Subclass- Gamopetalae

Stamens in 2/more series, epipetalous,                            

Ovary superior, carpels more than two                             Series- Heteromerae

Stamens as mane as petals, ovary with 2-many locules   Order- Ebenales

                                                                                                Family- Sapotaceae  

Distribution: Members of this family are distributed throughout the tropical countries with 600 species from 40 genera. In India this family is represented by 52 species and 10 genera. Common species are Achras sapota, Madhuca indica, Manilkara hexandra, Mimusops elengi, Sideroxylon tomentosum, Chrysophyllum cainito, Madhuca indica, etc. Most of them are economical important.

Salient features:

Plants shrubs or trees with milky latex in all plant parts. Young branches are rusty or tomentose. Stem with milky latex.

Leaves are simple, alternate or sub-opposite (Sacrosperma), entire at margin, coriaceous, leathery. Stipules are usually absent but spiny in Sideroxylon. Leaves are with milky latex.

Flowers are solitary or axillary in cymose clusters or in simple or compound panicle (Sacrosperma). Sometime cauliflory found in Madhuca & Dichopsis. Flowers are bisexual, Actinomorphic & hupogynous, bracteates. Trimerous in Palaquium & Manilkara; pentamerous in Sideroxylon.

Calyx- 4-8 sepals, some time in two whorls, free or sometime united at base. Sepals are in imbricate, in two whorls. Outer one is valvate & persistent.

Corolla- equal to number of sepals. Sometime 2-4 times than sepals, gamopetalous which form a rotate or urceolate or funnel shaped. Some time a spur or appendage is present in dorsal side. Petals are caduceus in Mimusops & Madhuca. In Mimusops a pair of appendages and the corolla appears like biseraite with 18-24 lobes.

Androecium- in 2-3 whorls of 4-5 each, epipetalous. In Madhica stamens are 2-3 times as many as corolla lobes set in 2-3 whorls. Some time outer stamens are reduced to staminodes as in Mimusops. Anthers are dithecous, dehising longitudinally with short filament.

Gynoecium- with 4-5 carpels, syncarpous, with 4-5 locualr ovary. Each locule with single, unitegmic, anatropous ovule. Placentation is axile. Style is one persistant.

Fruit- 1-8 seeded berry with laticiferous duct in inner pulp. Rarely one seeded, drupe like fruit. Seeds are exalbuminous, embryo with small radical & broad folaceous cotyledons.

Note- Pollination by insects. Fruits are dispersed by birds, animals or water current.

Floral formula:

Floral diagram:

Morphological peculiarities:

Plant body is latex bearing.

Young branches & leaves are tomentose.

Corolla biseriate, stamens in 2-3 whorls with dithecous anthers.

Ovary with axile placentation, style persistent.

Fruits 1-8 seeded berry with laticiferous sacs & axalbuminous seeds.

Economic importance & their uses-

Due to delicious fruits of Calocarpa sapota (Marmelade Plum), Chrysophyllum cainito, Vittelaria mammosa, Manilkara hexandra, Mimusops elengi are economically very important. 

Flowers of Madhuca indica for distilling alcohol and the seeds yield mahua butter (oil) which is use in cooking, laminating, to cure skin diseases & rheumatism.

Seeds of Madhuca butyracea produces vegetable butter which is useful as a cold cream & luminant.

Fruits of Achras sapota (Cikku/Sapodilla plum) is cultivated for edible fruits and the latex is used in making chewing gum.

Bakul plant-Mimusops elengi (Bakul) produces scented flowers. Timber is also produces from very hard wood of ‘Bakul’. The tannin from its wood is used for dying sails & fishing pickles.

Gutta Parcha- Palaquium gutta- yield milky latex which is a chief source ‘Gutta Purcha’ of commerce. This useful as insulator.

Many of them are cultivated for their ornamental foliage and scented flowers.

Present status, affinities, phylogeny & inter-relationship of Sapotaceae:

1.      The family Sapotaceae is closely allied to Ebenaceae and related to Strychaceae, Symplocaceae and Lissocarpaceae.

2.      According Hallier Sapotaceae placed as monotypic order Sapotales.

3.      Benthan & Hokker included it in order Ebenales which has been accepted by Hutchinson, Takhtajan & Cronquist.

4.      Thorne kept it under order Styricales.

5.      According to APG classification Sapotaceae placed in APG Group 4: Eudicots-Asterids in the order Ericales.